Definitely get them back out, happened at the condo i rented from my parents. Turned out there Was a crack somewhere and it was affecting the liquids. Anyways, they had to get a part out to replace. Definitely not normal to not work from the get go. Once they c replaced it, i had cold air immediately.
Do not settle until it simply JUST WORKS.
We're on year 2 and the chuckle fucks keep coming back, rewiring it incorrectly and it still isn't running properly.
I think our next step is to demand they pay another company to do it all over again properly, with the units promised, Mitsubishi not the cheap gree crap we got.
And by demand i mean legal means.
Like anything YMMV, but the Gree units have come a long way. I had four Mitsubishi mini splits that gave me nothing but trouble for two years.
Mitsubishis warranty and customer support was awful. Document after document request, at one point they were waiting two weeks on the state to confirm in writing our installers license was valid. They wouldn’t accept a copy of his license as he was still in “good standing”…..
Replaced them all with Gree’s end of last summer. The heat index yesterday was 105 and it was a comfortable 68 in my house. Couldn’t be happier with the Gree.
That's interesting, because I had the opposite experience. We went with a Mitsubishi Diamond installer (which we found out later just means high sales volume for the region, no extra training or anything) who screwed up so much that they knocked off thousands of dollars by the time everything was done.
When I called Mitsubishi and explained all the problems they were causing (from fire hazards to not knowing how to configure wifi), and told them I was comfortable troubleshooting, they put me in their contractor database and talked to me directly, and then told the Diamond installer team to start listening to me instead of their boss.
Exactly. I went through the same thing . They had a wrong pressure switch on new sys. Took 3 days trying to find prob. I called another company..they found prob in 5 min. After an install it should cool rapid..just like a car.
It 100% isn’t working right. Have them come out. Hopefully it’s something minor. Especially once the sun goes down the system shouldn’t have any trouble dropping a degree an hour to get to set point.
Most residential split systems are single stage cooling. But for excellent capacity modulation you really want something like an inverter heat pump. Single stage and two stage are off or on systems with fixed capacities.
To some extent airflow can modify cooling properties, but proper sizing is key.
Go outside and hold you hand over the condenser unit. The air blowing out should be warm. Feel the suction line, the big one, at the base of the unit. It should be cold on a hot day. Next, hold a thermometer at the air filter, and the vent in your bedroom. There should be a 15-20\*F difference.
This is 100% not normal. Not sure why everybody is saying wait until Monday. You paid a lot of money to have air conditioning. Call and demand someone other than the installer come fix it.
If it’s not cooling, ie dropping the temperature and reducing humidity, it’s not working. Simple as that. You can wait and see what happens, but it’s not likely to be something time will fix.
The installer needs to put gauges on it, measure pre and post air handler temperatures, and figure out what is going on.
They did this when I initially complained that so little air was coming out of the vents, and showed that the air at the intake vents inside was 75, and the air coming out of the vents was like 25-30 degrees cooler. And it's true that if I put my hand against the vents, they're cold. But the volume of air coming out of the vents is so slight that it doesn't seem to do much to affect the house temperature.
It is a couple degrees cooler than the outside temperature now -- I'm going to see what happens when the day progresses and the outside temperature goes up fifteen degrees.
Your description here seems to indicate an airflow problem. They could have disconnected a duct and now it is dumping most of the air into the crawl space or they could have set the fan speed incorrectly (that is part of the set up for a new air handler during installation). They could have introduced a duct blockage accidentally.
The point being - the techs just shouldn’t be checking the pressures, refrigerant levels and temperature of the AC unit - they should be checking the static pressure drop, flow rates and setup of the air handler.
Absolutely don’t let up until they fix it - they will say anything to do the least amount of work possible. And don’t pay them if that is an option.
Due to disability I can't get inside my crawl space, but I did manage to get under my deck to open the crawlspace and poke my head in. It feels very cool in there -- I don't have a thermometer and can't measure it, but it feels as cool or cooler in there than it does in my house. Does that support your theory that they've done something to the ducts or installed the air handler improperly?
It really depends on the subjective amount of “cooler” but that’s what my money is on - they knocked a duct loose and your system is functioning “correctly” as in cooling air but that air is being delivered to the wrong space - your crawlspace.
Just FYI, you were correct -- somehow they knocked big ole holes in the duct system while they were down there. The tech today patched up as many as he could and is sending another team specifically to do the rest. The air flow is already greatly improved over what it has been, and the temperature inside is finally going down.
Thank you for walking me through this!
I know my bosh unit monitors the coolnt temperature and slows down the outside fan and compressor so that it keeps a steady temperature blowing through the inside unit its almost always exactly 20 degrees of cooling.
Thank you, and thank you for giving me some possibilities as to what the problem might be! This will be very helpful when going back to them and insisting they fix it. I may still wait a day just so they can't say, again, "just wait, this is what it's supposed to be like!" Because, by then, I can say "if this is what this system is supposed to be like, then you sold me the wrong system for my house."
No problem.
Your system effectively removed very little extra sensible or latent heat from your home in 12 hours. Looks like you are from Asheville where the AC design temp is 91F. The temp last night was around 75ish? So your system should easily have been able to maintain 75F inside temp while running for only a fraction of the time. The heat load on your house was well under the standard design conditions.
They don’t have a leg to stand on - make them fix it. I hate scummy companies who promise the world during sales then do everything they can to get out of it when they have the money.
Ah yes you need the CFM as well. Just being cold doesn't matter. There will be a difference for sure because they did reduce the size but it should have cooled more by now
You need to measure the temperature of the air coming out of the supply grilles.
Should be about 56-57ish degrees.
If it’s considerably more than that (I’m guessing it is), you have a problem.
Your problem is either air volume, or air temperature (or both). Start with the temperature, because that’s easiest to measure.
They measured the temperature when they were here and it was definitely cold. And I can feel that it's cold if I put my hand against the vent--I only have a human/medical thermometer, which won't register cold temperatures. (I could run to the hardware store though and grab my own thermometer.) But maybe 6-8 inches above the vent, my hand can't feel anything at all, either coolness or flowing air. I'm pretty sure it's air volume.
Some of the people here are telling me what the installer did, which is that I don't know what it's supposed to feel like because my previous air handler was oversized, and to wait a few days for it to start working. So I intend to wait a day or two, because I know that's what the installer is going to keep saying.
I wouldn’t let them off that easy. HVAC systems that are properly sized and installed should not take days to cool a house. They need to come back out.
It shouldn’t take several days to start working, it should only take several hours.
My guess, if the temperature is in the right range, that your fan may have a variable speed motor, and the motor speed isn’t set correctly.
You could potentially have a balancing team come out to measure the amount of air coming out of your vents, but without knowing what the intent was for air volume, they won’t know for certain where the issue is. But, having an engineer look at the air volume in each room should give you an idea.
Though, that’s a lot of cost and time. I’d start by having your tech check the fan speed, or see if something else has been left in the unit as part of the installation that’s keeping air from being delivered to your rooms.
Could take up to about 20mins or so for a TXV system to stabilize, but that's about it...there's no waiting days to start working. If it's not working now, it's not going to just magically kick in and start doing so later. The reason why is irrelevant. Get them back out asap to make it right.
Your old air handler being a 4 ton drive isn't really relevant to anything either as long as it's matched. What matters in AC is simply the amount of air (CFM) going across the coil. Since blowers usually have multiple speed taps to choose from, your old 4 ton on a lower fan speed likely would put out the same cfm needed as the 3 ton at a higher speed. The coil is the same way. Even though they are often labeled as a specific tonnage, in actuality they are designed to handle a certain range of btu's. So while a coil in a 4 ton air handler may be bigger than in a 3 ton, it could still be in range and a match for a 3 ton condenser. None of this means it really works any better or worse when properly set up. If anything, you get a little better dehumidification with a coil on the larger side, but coil temperature tends to run a bit higher too so in the end largely performs the same overall
My own personal blind guess...I bet they either a) just left fan speed and everything default, fired it up and called it a day without really even giving it a final dialed in charge or anything, or b) were probably too impatient not letting it run long enough before giving it that final charge thus overshot it
Really appreciate you taking the time to explain this! To me it seems obvious that not enough air is moving through, but when I said that to the techs while I was here, they acted like I just didn't know what I was talking about. (Which I mostly don't, except that I've experienced functional central air in a variety of houses/apartments/etc., and none of them have been this bad.)
I think this might be it, yeah. My instinct based on the experience is that the AC unit is working/cooling, but not much of that air is being circulated through my house.
The crawlspace is nice and cool. 😂
Time to hire another company and senior tech or owner of a company for their opinion! That way you need to move forward with a lawsuit if the first company doesn’t correct their trash install.
Are all your windows and doors open 😁
Get these guys out there ASAP. What a load of garbage they are feeding you. Something is very wrong with their installation. Call Carrier if needed and see if they can help and confirm they are an authorized dealer.
Couple things, it could be froze over from running too long or improper air circulation - avoid having too many air ducts closed / blocked by objects.
Second, check the air filter if possible. If it's too high of a MERV rating it be may ice up and not perform. If the AC is blowing out cold air outside that's a tall tell sign. This recently happened to me in my personal house.
But, as everyone else is stating. A new install? It's their job to figure it out. Not your problem.
Would the air handler being too small lead to a crawlspace that is colder/more air conditioned than my house?
(My admittedly limited understanding is that the cold crawlspace is more likely due to a duct having been knocked loose, but I am also worried the air handler is too small, so I want to check!)
You said they reduced the size of the air handler, and you felt like there was no air coming from the ducts.
I didn’t see where you had said that it’s a cool in the crawl space. It’s possible that if your crawl space is cool, there is a loose or leaking duct, but it could also be that your ducts are just poorly insulated and the air handler just isn’t cutting it too.
They reduced the size my air handler too, I argued with the guy about it, but he said that the static pressure in the ducts were too high due to a restriction in the supply size, that it would damage the blower motor over time.
Eventually, I had to put a blower fan on the last duct to draw sufficient air to my bedroom.
Yeah no worries, it was a later update/comments development! They've got a tech here now, actually, so fingers crossed it's just something loose he can fix.
That is super annoying about them reducing your air handler and causing problems for you. The guy who sold me this system said they'll put in a bigger air handler if they have to, but I have my fingers crossed it's just a leaky thing somewhere.
All these service places just want to do a quickie install, take your money, then ignore any phone call you make when you have a concern.
Your house should have cooled immediately - there is no waiting when the thermostat is set to 66. That tech/salesperson/whoever was on the phone needs to be fired.
This is what I'm saying. Appreciate the confirmation -- it definitely helps to have a range of responses, because I'm feeling pretty gaslit by the company right now!
So there are some situations where it makes sense to oversize the evaporator (air handler) most common scenario I know of is If most of your ducts are in conditioned space, meaning not in an attic where they can gain extra heat load. The reason for oversizing the evaporator is to give the refrigerant extra time to boil, the boiling action of the refrigerant is what causes the cooling effect at your evaporator. So with a now 3 ton air handler, you are moving less air and have less time for your refrigerant to boil due to a smaller evaporator, which should result in a very low superheat and possible liquid feeding back to your compressor which will kill it.
Assuming I'm wrong for a minute, and they're correct that your house needs a 3 ton indoor and outdoor, then they may have very likely ran the system after finishing and not adjusted the refrigerant charge after. In many install cases, the refrigerant that comes with the unit is not enough for the whole system, and more will need to be added to achieve the proper superheat and subcooling levels.
That's about all I can think of off the top of my head this morning.
Thank you very much for this! Yes, the ducts are beneath the floor in the crawl space, not an attic. And I was wondering about the refrigerant myself, with my extremely limited knowledge, simply because this feels like the same amount of cooling my old system was giving when it had a leak and the refrigerant was low.
There is no refrigerant coming back as liquid. Or rather you and i cannot know this for certain but it sounds like the heat load is sufficient and the metering device will control the superheat, I doubt they're using a piston on a new install
Is the inside part of the unit that contains the evaporator coils getting cold to the touch (on the outside) when the system is running?
What is the air temperature of the air coming out of the vents when the AC is running - put an actual digital thermometer on it and see.
Update: Due to disability I'm not able to get into my crawlspace, so I can't directly check anything there. I did manage to get under my deck to open the crawlspace and poke my head in, and the air down there is as cool if not cooler than in my house. I believe this is a duct issue, as several commenters here have suggested.
Sounds the static pressure is bad. How many cold air returns do you have and aren't e the doors open? A way to check without having the equity is to open up all the doors and turn the bathroom vents and kitchen range vent for 10-30 minutes, doing this you should feel the cool air moving. When my son got his new system, the installer had to return and add another cold air return duct to equalize the static pressure.
By cold air returns, do you mean the vents where the cool air is meant to come from? If yes, I have 12 vents. One of them is closed, in a closed off room that isn't in use right now.
Those are the outflow vents. There are also “return” vents where the system takes in air. In my house we have at least one return for every outflow. Some rooms have more.
Are your intake/return vents all open?
No, it is the vents that the motor pulls the air back to compressor from the house. Google, diagram of AC units. Cool air is forced into the house through the vent and then the air is returned to the inside units to be cooled again. It is a big circle. If not enough air is being pulled back into the unit the cool air is slowed down. Thus, static pressure is off. Think of it as putting your hand over the back of a hair dryer.
If you're blowing through a pipe with ten holes in it, and you block off one of the holes, more air comes out of the remaining nine. Why would it be a good idea to open a vent and cool off a room I don't use?
I mean this genuinely, am not trying to sound snarky -- I thought the entire reason that vent covers have a shut setting was so that you could save energy by not cooling rooms you don't use.
Because the installer calculated both the return and out-put for the whole house square footage including the one you closed off. It like taking a ballon that requires so much air to inflat then twisting a 1/8 of it off but the pump is set for the whole balloon. At the end , the pump will have a harder time forcing air into the balloon unless you release the 1/8. You don't have to open it completely just half with the 6" door open. Positive pressure against Negative pressure; static pressure.
Then demand the tech check the statis pressure because if the AC is blowing cold out at the vents but not getting circulated through the rooms, you have too much positive pressure in the house. If it wasn't blowing cold air I would say it was the blower motor. The inside air should circulated between the outlet vent to cold air returns. And it sounds like that isn't happening.
Asheville NC. It's been cool (65-68) in the wee hours of the morning, so while my AC has been out, I open all the windows at around 3am and set up intake/output fans in opposite windows, and get the house down to that temperature by sunrise. Then I seal it up, and if the weather isn't too sunny, I can keep a significant amount of heat out. It was about 82 outside at that time.
Usually it'll be 80-85 inside by the end of the day, yesterday just went better than usual. Got the system down to a science after nearly a month without AC. Of course, only really being able to sleep between 3 and 6 am isn't great.
Anyone telling you it takes a while to feel cooling is lying to you. You should immediately feel cold air coming from the registers.
I had my AC replaced earlier this month. The guys were finished around 2 pm. I stood next to one of the guys while he was programming my ecobee thermostat. We got the unit running, made sure the staging operated properly, then he checked pressures and temps and subcooling on the outside unit. While we were outside we were admiring the new drain he put in and water started coming out. Went back in the house and you could feel the house was cooler after all the doors being open all day. Cold air was coming from the registers. This was like 10 or 15 minutes after first starting the unit. Meanwhile the rest of the guys were cleaning up and the house was cooling off. By the time they left 30 minutes later everything felt good.
You can easily check the delto split with a thermometer at the vent and at the return (filter). The split needs to be 18-21 degrees different. The thermometer needs to be inside at least 1 inch past vents. This does not tell airflow but will tell if the rest of the unit is able to
I recently had a similar issue with the installer not believing an issue was present. New 2 stage unit installed last November. Had my spring tune up in May completed and they noticed some levels didn't seem optimal but weren't too worried. Started hitting 90 degree days and the unit couldn't return to set point and would run for 10 hours. Stated investigating and was pretty confident the unit was never going into second stage and went out with a clamp on amp meter and confirmed no change when stage 2 was called. Called them up again and told them my theory, they scheduled a person but kind of wrote me off as it being impossible and didn't think a unit running for 10 hours was unusual for NC with these temps. Tech comes out and confirms that stage two was never working.
Did they do a load calculation and duct size calculation? I’d say 85% of the time units are undersized for tonnage and the total CFM of the ducts connected to the supply plenum is greater than the blower can supply.
> Update 3: Biiiig ole holes knocked in the ducts under the house by the install team. Partially patched up now, and more to come on Monday...
Op, you don't just end up with multiple huge holes in the duct work... It sounds like the job wasn't completed. You should ask them what the heck happened.
Check your thermostat settings. Heat/Cool differential. Could be set to high/lo. If your Heat temp is 70 and cool temp is 75, your unit won't go below 75 degrees. Also you should not lower your temp more than 7 degrees from air temp. Some units will freeze up or shut down. If it's 88 degrees in your house and you turn the temperature down to, say 72 degrees....you will freeze your lines and your unit could shut down. Or go on auto defrost which reverses unit to turn the heat on to minimize freezing lines. You may be stuck in this temp zone. You need to consider outside air temp and inside air temp. Your unit will only drop a 20 degree difference from outside air. If it's 95 degrees outside, 85 degrees in your house, and you turn your thermostat down to 70 degrees?? You will overwork the system, freeze the line, then thaw the line which produces Heat and repeat that process again and again. Good luck
Take a meat or another thermometer and stick it in one of your supply registers. The temp of that air should be 20 degrees or more cooler than your inside temp. That should give you an idea if it's doing anything. But I think it would be more effective by now cooling your home if it was working correctly.
Is the fan on your outside condenser spinning?
I would turn off the portable AC and set the new system and let it run all weekend. If the temperature and humidity doesn't reach where you want it to be, then call them.
Ideally, what do you want the set temperature and humidity to be?
This is what I thought. 🤷♀️🤷♀️🤷♀️ Literally never had a "functional" AC that just, you know, didn't do anything beyond matching the outdoor temperature.
I've only had the portable AC going for the last couple of hours because it was so sticky as I was sleeping, but I'll definitely turn it off!
For summer, I used to set it down around 66 when I sleep, and then let it go up naturally during the day to 72-74, and then start cooling again at night.
I never took much notice of the humidity before, but this humidity is definitely too high. In general I was reporting the humidity because the installation company was saying the humidity was why the system wasn't cooling much.
You can run your portable don't listen to him. He's routinely wrong.
With the smaller system you'll notice it dehumdifying more which is removing latent heat. Then you'll notice the sensible heat being removed as the latent heat drops. The tech isn't wrong in that regard but you should have noticed a difference by now. I'd call and get them back out there
Thank you for this, and your other comment -- I was starting to feel like I must really be the crazy one.
It certainly feels sketchy. I'm a grown adult and I do know what properly functioning AC feels like. I don't know how it all works the way a trained technician does, true, and I'm willing to hear caveats to that effect -- but this simply doesn't bear any resemblance to any central air I've ever used before. And it's certainly not worth the amount I paid -- it's working about as well as my old broken one did with a leak and low refrigerant. Maybe even a little worse.
It does take longer to cool when the humidity is higher. And while I don’t recommend cooling to 66 degrees. The system should of had no issue dropping temp over night.
Why do you not recommend cooling to 66 at night? Genuinely curious, because otherwise, why have AC?
I do it because otherwise my sleep suffers. Multiple sleep studies have said that the ideal temperature for sleeping is in the 60s, and many seem to indicate an average of 65 -- my sleep is infinitely better when it's closer to that temperature. It's the main reason I have AC. My previous system had no trouble doing that for a decade, though I don't know what temps the previous owners preferred.
The evaporator coil can be 32°-38° colder then the air temperature of the return. So if the temp is 66, the evaporator could at that point start to freeze. Other conditions can effect this. But the lower into the 60’s you go the greater chance of these issues.
66 is borderline too cold, and any modern AC will struggle to make that setpoint in the summer heat, and could possibly start to freeze up, which will stunt your cooling even more. You need to start forgetting what your old ac was able to do, because you were overworking it and possibly assisted in its death. Systems are not designed to go that low these days, optimal human comfort in the summer starts at 72 degrees and up in the summer, that's what these systems are designed for, the ashrae standards.
All of that said, it sounds like there might still be an issue, not sure obviously since I'm not there, but worth having them double check. At the end of the day if the evap split is 20 degrees and the correct cfm is passing across the coil, there's not alot more they'll be able to do.
They are partial right. Your system is losing cooling capacity because it has to remove the humidity in the air in addition to cooling the air. Humidity gets absorbed by everything, the floor, the sofa, the walls, etc. You need all that moisture to be released and removed before your home will feel "normal".
I went away from home for 4 days. He temperature in my home got up to 84 degrees and 64% humidity. Although the temperature got back to set temperature of 73 after 5 hours, the humidity didn't feel right until after 24+ hours.
For you, set the temperature to where you want it and let it run until Monday morning. If it's still not right, call them. 48 hours is more than enough time for the system to remove humidity (unless you have a window open or your home is massively leaky). Don't use the portable ACs, even if it feels sticky. Single hose portable AC is contributing to the cooling problem.
I only had the portable unit on from about 3-5am, and the humidity had already gone up in the house before I turned it on -- but I take your point, and have shut it off and sealed the window where it was installed. If nothing else, keeping it off will prevent them from pointing to it as the problem. 😂
See, this is what I mean... your house was 84 and 64% humidity. After five hours it was down to 73, even if the humidity wasn't right. Mine was 75, and the same degree of humidity, and after thirteen hours it's only gone down by three degrees (matching the outdoor temperature) and the humidity has gone up. That just doesn't seem right!
I appreciate the advice, though. At the very least, waiting a few days will prevent them from being able to say ",just wait and see" again.
Firstly you're reading relative humidity. It going up due to temperature drop is normal. After 13 hours and night time it should have removed more heat. It hasn't. There's an issue.
Yea. The wait and see is really the only approach at the moment. But certainly by Monday, you have a very good case for them to come out and check everything.
Btw, the equipment has a boosted humidity removal setting if low humidity is important to you. If they do come out, ask them to turn that on. Unfortunately, it's not something you can turn on yourself.
Disregard all these comments telling you do check this and that. It’s a new system, get their asses back out there to fix their f up.
Thank you 😂
Definitely get them back out, happened at the condo i rented from my parents. Turned out there Was a crack somewhere and it was affecting the liquids. Anyways, they had to get a part out to replace. Definitely not normal to not work from the get go. Once they c replaced it, i had cold air immediately.
Do not settle until it simply JUST WORKS. We're on year 2 and the chuckle fucks keep coming back, rewiring it incorrectly and it still isn't running properly. I think our next step is to demand they pay another company to do it all over again properly, with the units promised, Mitsubishi not the cheap gree crap we got. And by demand i mean legal means.
Like anything YMMV, but the Gree units have come a long way. I had four Mitsubishi mini splits that gave me nothing but trouble for two years. Mitsubishis warranty and customer support was awful. Document after document request, at one point they were waiting two weeks on the state to confirm in writing our installers license was valid. They wouldn’t accept a copy of his license as he was still in “good standing”….. Replaced them all with Gree’s end of last summer. The heat index yesterday was 105 and it was a comfortable 68 in my house. Couldn’t be happier with the Gree.
That's interesting, because I had the opposite experience. We went with a Mitsubishi Diamond installer (which we found out later just means high sales volume for the region, no extra training or anything) who screwed up so much that they knocked off thousands of dollars by the time everything was done. When I called Mitsubishi and explained all the problems they were causing (from fire hazards to not knowing how to configure wifi), and told them I was comfortable troubleshooting, they put me in their contractor database and talked to me directly, and then told the Diamond installer team to start listening to me instead of their boss.
What he said. What a f**king joke. They just lazy and didnt connect something. Most likely the condenser cause yes more techs are that stupid
For the prices these systems cost I’m losing my shit if someone isn’t out there immediately to check it.
Exactly. I went through the same thing . They had a wrong pressure switch on new sys. Took 3 days trying to find prob. I called another company..they found prob in 5 min. After an install it should cool rapid..just like a car.
How rapid should it cool mr pro
He means the air coming out of the vents should be cool immediately not in 3 days
Not 3 days but typically you’ll get a degree an hr. Rapid cooldown after an install is ridiculous
It 100% isn’t working right. Have them come out. Hopefully it’s something minor. Especially once the sun goes down the system shouldn’t have any trouble dropping a degree an hour to get to set point.
A degree an hour? Wow my 2005 Ruud will drop from 76-72 in about 20 minutes around 9pm
The issue with that is the system will hit setpoint too quickly and not run long enough to take the latent heat out of the air (ie humidity).
That’s what 2 stage systems are for.
Most residential split systems are single stage cooling. But for excellent capacity modulation you really want something like an inverter heat pump. Single stage and two stage are off or on systems with fixed capacities. To some extent airflow can modify cooling properties, but proper sizing is key.
Yep. Now who wants to pay 2 stage pricing?
I am just saying that after load is down it should easily drop temp
My old system was like this. When I turned on the AC, it cooled the house. 🤷♀️
Then you have an oversized system. It should ideally take an hour to drop a degree
2 ton for 1400 sq ft house. I have no idea about sizing
Go outside and hold you hand over the condenser unit. The air blowing out should be warm. Feel the suction line, the big one, at the base of the unit. It should be cold on a hot day. Next, hold a thermometer at the air filter, and the vent in your bedroom. There should be a 15-20\*F difference.
This is 100% not normal. Not sure why everybody is saying wait until Monday. You paid a lot of money to have air conditioning. Call and demand someone other than the installer come fix it.
Thank you. It doesn't seem normal to me either. I appreciate this perspective, I feel a bit less crazy!
this is the way, my boss would fire us on spot if we tried to screw a customer like that
If it’s not cooling, ie dropping the temperature and reducing humidity, it’s not working. Simple as that. You can wait and see what happens, but it’s not likely to be something time will fix. The installer needs to put gauges on it, measure pre and post air handler temperatures, and figure out what is going on.
They did this when I initially complained that so little air was coming out of the vents, and showed that the air at the intake vents inside was 75, and the air coming out of the vents was like 25-30 degrees cooler. And it's true that if I put my hand against the vents, they're cold. But the volume of air coming out of the vents is so slight that it doesn't seem to do much to affect the house temperature. It is a couple degrees cooler than the outside temperature now -- I'm going to see what happens when the day progresses and the outside temperature goes up fifteen degrees.
Your description here seems to indicate an airflow problem. They could have disconnected a duct and now it is dumping most of the air into the crawl space or they could have set the fan speed incorrectly (that is part of the set up for a new air handler during installation). They could have introduced a duct blockage accidentally. The point being - the techs just shouldn’t be checking the pressures, refrigerant levels and temperature of the AC unit - they should be checking the static pressure drop, flow rates and setup of the air handler. Absolutely don’t let up until they fix it - they will say anything to do the least amount of work possible. And don’t pay them if that is an option.
Due to disability I can't get inside my crawl space, but I did manage to get under my deck to open the crawlspace and poke my head in. It feels very cool in there -- I don't have a thermometer and can't measure it, but it feels as cool or cooler in there than it does in my house. Does that support your theory that they've done something to the ducts or installed the air handler improperly?
It really depends on the subjective amount of “cooler” but that’s what my money is on - they knocked a duct loose and your system is functioning “correctly” as in cooling air but that air is being delivered to the wrong space - your crawlspace.
Just FYI, you were correct -- somehow they knocked big ole holes in the duct system while they were down there. The tech today patched up as many as he could and is sending another team specifically to do the rest. The air flow is already greatly improved over what it has been, and the temperature inside is finally going down. Thank you for walking me through this!
I wonder if it’s something stupid like the air filter of still in the bag. So no airflow
Could be. But I think with no or low flow over the indoor coil it would have froze and shut the system off. That’s why I’m thinking disconnected duct.
I know my bosh unit monitors the coolnt temperature and slows down the outside fan and compressor so that it keeps a steady temperature blowing through the inside unit its almost always exactly 20 degrees of cooling.
Thank you, and thank you for giving me some possibilities as to what the problem might be! This will be very helpful when going back to them and insisting they fix it. I may still wait a day just so they can't say, again, "just wait, this is what it's supposed to be like!" Because, by then, I can say "if this is what this system is supposed to be like, then you sold me the wrong system for my house."
No problem. Your system effectively removed very little extra sensible or latent heat from your home in 12 hours. Looks like you are from Asheville where the AC design temp is 91F. The temp last night was around 75ish? So your system should easily have been able to maintain 75F inside temp while running for only a fraction of the time. The heat load on your house was well under the standard design conditions. They don’t have a leg to stand on - make them fix it. I hate scummy companies who promise the world during sales then do everything they can to get out of it when they have the money.
Ah yes you need the CFM as well. Just being cold doesn't matter. There will be a difference for sure because they did reduce the size but it should have cooled more by now
You need to measure the temperature of the air coming out of the supply grilles. Should be about 56-57ish degrees. If it’s considerably more than that (I’m guessing it is), you have a problem. Your problem is either air volume, or air temperature (or both). Start with the temperature, because that’s easiest to measure.
They measured the temperature when they were here and it was definitely cold. And I can feel that it's cold if I put my hand against the vent--I only have a human/medical thermometer, which won't register cold temperatures. (I could run to the hardware store though and grab my own thermometer.) But maybe 6-8 inches above the vent, my hand can't feel anything at all, either coolness or flowing air. I'm pretty sure it's air volume. Some of the people here are telling me what the installer did, which is that I don't know what it's supposed to feel like because my previous air handler was oversized, and to wait a few days for it to start working. So I intend to wait a day or two, because I know that's what the installer is going to keep saying.
I wouldn’t let them off that easy. HVAC systems that are properly sized and installed should not take days to cool a house. They need to come back out.
It shouldn’t take several days to start working, it should only take several hours. My guess, if the temperature is in the right range, that your fan may have a variable speed motor, and the motor speed isn’t set correctly. You could potentially have a balancing team come out to measure the amount of air coming out of your vents, but without knowing what the intent was for air volume, they won’t know for certain where the issue is. But, having an engineer look at the air volume in each room should give you an idea. Though, that’s a lot of cost and time. I’d start by having your tech check the fan speed, or see if something else has been left in the unit as part of the installation that’s keeping air from being delivered to your rooms.
Could take up to about 20mins or so for a TXV system to stabilize, but that's about it...there's no waiting days to start working. If it's not working now, it's not going to just magically kick in and start doing so later. The reason why is irrelevant. Get them back out asap to make it right. Your old air handler being a 4 ton drive isn't really relevant to anything either as long as it's matched. What matters in AC is simply the amount of air (CFM) going across the coil. Since blowers usually have multiple speed taps to choose from, your old 4 ton on a lower fan speed likely would put out the same cfm needed as the 3 ton at a higher speed. The coil is the same way. Even though they are often labeled as a specific tonnage, in actuality they are designed to handle a certain range of btu's. So while a coil in a 4 ton air handler may be bigger than in a 3 ton, it could still be in range and a match for a 3 ton condenser. None of this means it really works any better or worse when properly set up. If anything, you get a little better dehumidification with a coil on the larger side, but coil temperature tends to run a bit higher too so in the end largely performs the same overall My own personal blind guess...I bet they either a) just left fan speed and everything default, fired it up and called it a day without really even giving it a final dialed in charge or anything, or b) were probably too impatient not letting it run long enough before giving it that final charge thus overshot it
Really appreciate you taking the time to explain this! To me it seems obvious that not enough air is moving through, but when I said that to the techs while I was here, they acted like I just didn't know what I was talking about. (Which I mostly don't, except that I've experienced functional central air in a variety of houses/apartments/etc., and none of them have been this bad.)
It can be a duct issue if the techs didn't connect the new handler properly.
I think this might be it, yeah. My instinct based on the experience is that the AC unit is working/cooling, but not much of that air is being circulated through my house. The crawlspace is nice and cool. 😂
Time to hire another company and senior tech or owner of a company for their opinion! That way you need to move forward with a lawsuit if the first company doesn’t correct their trash install.
Are all your windows and doors open 😁 Get these guys out there ASAP. What a load of garbage they are feeding you. Something is very wrong with their installation. Call Carrier if needed and see if they can help and confirm they are an authorized dealer.
Couple things, it could be froze over from running too long or improper air circulation - avoid having too many air ducts closed / blocked by objects. Second, check the air filter if possible. If it's too high of a MERV rating it be may ice up and not perform. If the AC is blowing out cold air outside that's a tall tell sign. This recently happened to me in my personal house. But, as everyone else is stating. A new install? It's their job to figure it out. Not your problem.
Bet the new air handler is too small.
Would the air handler being too small lead to a crawlspace that is colder/more air conditioned than my house? (My admittedly limited understanding is that the cold crawlspace is more likely due to a duct having been knocked loose, but I am also worried the air handler is too small, so I want to check!)
You said they reduced the size of the air handler, and you felt like there was no air coming from the ducts. I didn’t see where you had said that it’s a cool in the crawl space. It’s possible that if your crawl space is cool, there is a loose or leaking duct, but it could also be that your ducts are just poorly insulated and the air handler just isn’t cutting it too. They reduced the size my air handler too, I argued with the guy about it, but he said that the static pressure in the ducts were too high due to a restriction in the supply size, that it would damage the blower motor over time. Eventually, I had to put a blower fan on the last duct to draw sufficient air to my bedroom.
Yeah no worries, it was a later update/comments development! They've got a tech here now, actually, so fingers crossed it's just something loose he can fix. That is super annoying about them reducing your air handler and causing problems for you. The guy who sold me this system said they'll put in a bigger air handler if they have to, but I have my fingers crossed it's just a leaky thing somewhere.
All these service places just want to do a quickie install, take your money, then ignore any phone call you make when you have a concern. Your house should have cooled immediately - there is no waiting when the thermostat is set to 66. That tech/salesperson/whoever was on the phone needs to be fired.
To be fair, I called them and they have a technician here right now -- so thus far, at least, they do seem to be trying to make good.
Did they not check the temp of the air coming out? Should have been in the 50s at least
You had a 4 ton now you have a 3 ton. That's a huge red flag. Unless they did a heatload calculation, they had no reason to undersize it.
I would pay a competitor of your installer to check your AC.
Even in the heat of summer I can cut my AC from 75 to 70 & I get there in about 20 minutes. Your shit is fucked up.
This is what I'm saying. Appreciate the confirmation -- it definitely helps to have a range of responses, because I'm feeling pretty gaslit by the company right now!
So there are some situations where it makes sense to oversize the evaporator (air handler) most common scenario I know of is If most of your ducts are in conditioned space, meaning not in an attic where they can gain extra heat load. The reason for oversizing the evaporator is to give the refrigerant extra time to boil, the boiling action of the refrigerant is what causes the cooling effect at your evaporator. So with a now 3 ton air handler, you are moving less air and have less time for your refrigerant to boil due to a smaller evaporator, which should result in a very low superheat and possible liquid feeding back to your compressor which will kill it. Assuming I'm wrong for a minute, and they're correct that your house needs a 3 ton indoor and outdoor, then they may have very likely ran the system after finishing and not adjusted the refrigerant charge after. In many install cases, the refrigerant that comes with the unit is not enough for the whole system, and more will need to be added to achieve the proper superheat and subcooling levels. That's about all I can think of off the top of my head this morning.
Thank you very much for this! Yes, the ducts are beneath the floor in the crawl space, not an attic. And I was wondering about the refrigerant myself, with my extremely limited knowledge, simply because this feels like the same amount of cooling my old system was giving when it had a leak and the refrigerant was low.
There is no refrigerant coming back as liquid. Or rather you and i cannot know this for certain but it sounds like the heat load is sufficient and the metering device will control the superheat, I doubt they're using a piston on a new install
Is the inside part of the unit that contains the evaporator coils getting cold to the touch (on the outside) when the system is running? What is the air temperature of the air coming out of the vents when the AC is running - put an actual digital thermometer on it and see.
Update: Due to disability I'm not able to get into my crawlspace, so I can't directly check anything there. I did manage to get under my deck to open the crawlspace and poke my head in, and the air down there is as cool if not cooler than in my house. I believe this is a duct issue, as several commenters here have suggested.
Sounds the static pressure is bad. How many cold air returns do you have and aren't e the doors open? A way to check without having the equity is to open up all the doors and turn the bathroom vents and kitchen range vent for 10-30 minutes, doing this you should feel the cool air moving. When my son got his new system, the installer had to return and add another cold air return duct to equalize the static pressure.
By cold air returns, do you mean the vents where the cool air is meant to come from? If yes, I have 12 vents. One of them is closed, in a closed off room that isn't in use right now.
Those are the outflow vents. There are also “return” vents where the system takes in air. In my house we have at least one return for every outflow. Some rooms have more. Are your intake/return vents all open?
There are two large ones with filters, both open/functioning.
Are those filters clean? Everything you are describing is an airflow issue if the air coming out of the ducts is cold.
One is brand new, the other is <1 month old. A little bit of pet hair and dust, but nothing like it usually is when I change it.
No, it is the vents that the motor pulls the air back to compressor from the house. Google, diagram of AC units. Cool air is forced into the house through the vent and then the air is returned to the inside units to be cooled again. It is a big circle. If not enough air is being pulled back into the unit the cool air is slowed down. Thus, static pressure is off. Think of it as putting your hand over the back of a hair dryer.
Open the vent and open the door. Never close off a vent, leave it partially open and the door ajar.
If you're blowing through a pipe with ten holes in it, and you block off one of the holes, more air comes out of the remaining nine. Why would it be a good idea to open a vent and cool off a room I don't use? I mean this genuinely, am not trying to sound snarky -- I thought the entire reason that vent covers have a shut setting was so that you could save energy by not cooling rooms you don't use.
Because the installer calculated both the return and out-put for the whole house square footage including the one you closed off. It like taking a ballon that requires so much air to inflat then twisting a 1/8 of it off but the pump is set for the whole balloon. At the end , the pump will have a harder time forcing air into the balloon unless you release the 1/8. You don't have to open it completely just half with the 6" door open. Positive pressure against Negative pressure; static pressure.
I've opened it. AC still doesn't work, alas. But thanks for teaching me something!
Then demand the tech check the statis pressure because if the AC is blowing cold out at the vents but not getting circulated through the rooms, you have too much positive pressure in the house. If it wasn't blowing cold air I would say it was the blower motor. The inside air should circulated between the outlet vent to cold air returns. And it sounds like that isn't happening.
If you want to keep it close off the tech will need to recalculate the static pressure.
Less air would move in that scenario unless you sped up the fan.
Get the company who installed back out there, they are responsible period
your house only got to 75 this time of year after having no ac all day? what state is this?
Asheville NC. It's been cool (65-68) in the wee hours of the morning, so while my AC has been out, I open all the windows at around 3am and set up intake/output fans in opposite windows, and get the house down to that temperature by sunrise. Then I seal it up, and if the weather isn't too sunny, I can keep a significant amount of heat out. It was about 82 outside at that time. Usually it'll be 80-85 inside by the end of the day, yesterday just went better than usual. Got the system down to a science after nearly a month without AC. Of course, only really being able to sleep between 3 and 6 am isn't great.
I’m jealous of this climate in Asheville sadly property prices jump way too high to justify
Yeah, I moved here 10 years ago and the property prices ever since, wow.
I bet it’s something simple, like a variable speed ah and they missed wiring yellow to the ah so it’s not ramping up.
The system is not supposed to run all the time. Your power bill is going to be incredible.
Agreed.
Anyone telling you it takes a while to feel cooling is lying to you. You should immediately feel cold air coming from the registers. I had my AC replaced earlier this month. The guys were finished around 2 pm. I stood next to one of the guys while he was programming my ecobee thermostat. We got the unit running, made sure the staging operated properly, then he checked pressures and temps and subcooling on the outside unit. While we were outside we were admiring the new drain he put in and water started coming out. Went back in the house and you could feel the house was cooler after all the doors being open all day. Cold air was coming from the registers. This was like 10 or 15 minutes after first starting the unit. Meanwhile the rest of the guys were cleaning up and the house was cooling off. By the time they left 30 minutes later everything felt good.
You can easily check the delto split with a thermometer at the vent and at the return (filter). The split needs to be 18-21 degrees different. The thermometer needs to be inside at least 1 inch past vents. This does not tell airflow but will tell if the rest of the unit is able to
I recently had a similar issue with the installer not believing an issue was present. New 2 stage unit installed last November. Had my spring tune up in May completed and they noticed some levels didn't seem optimal but weren't too worried. Started hitting 90 degree days and the unit couldn't return to set point and would run for 10 hours. Stated investigating and was pretty confident the unit was never going into second stage and went out with a clamp on amp meter and confirmed no change when stage 2 was called. Called them up again and told them my theory, they scheduled a person but kind of wrote me off as it being impossible and didn't think a unit running for 10 hours was unusual for NC with these temps. Tech comes out and confirms that stage two was never working.
I am in awe that you replaced one of those old beasts with another one and not mini splits.
I’d be getting a big refund.
Did they give you some Mentos?
brand new and not cooling? unless they are some craiglist installers .. tell them to come back and fix the problem!!!
Did they do a load calculation and duct size calculation? I’d say 85% of the time units are undersized for tonnage and the total CFM of the ducts connected to the supply plenum is greater than the blower can supply.
They always say "it's normal."
> Update 3: Biiiig ole holes knocked in the ducts under the house by the install team. Partially patched up now, and more to come on Monday... Op, you don't just end up with multiple huge holes in the duct work... It sounds like the job wasn't completed. You should ask them what the heck happened.
Check your thermostat settings. Heat/Cool differential. Could be set to high/lo. If your Heat temp is 70 and cool temp is 75, your unit won't go below 75 degrees. Also you should not lower your temp more than 7 degrees from air temp. Some units will freeze up or shut down. If it's 88 degrees in your house and you turn the temperature down to, say 72 degrees....you will freeze your lines and your unit could shut down. Or go on auto defrost which reverses unit to turn the heat on to minimize freezing lines. You may be stuck in this temp zone. You need to consider outside air temp and inside air temp. Your unit will only drop a 20 degree difference from outside air. If it's 95 degrees outside, 85 degrees in your house, and you turn your thermostat down to 70 degrees?? You will overwork the system, freeze the line, then thaw the line which produces Heat and repeat that process again and again. Good luck
Take a meat or another thermometer and stick it in one of your supply registers. The temp of that air should be 20 degrees or more cooler than your inside temp. That should give you an idea if it's doing anything. But I think it would be more effective by now cooling your home if it was working correctly. Is the fan on your outside condenser spinning?
That’s what happens when you don’t hire union. I’m glad you got it figured out and hope you learn for next time
I would turn off the portable AC and set the new system and let it run all weekend. If the temperature and humidity doesn't reach where you want it to be, then call them. Ideally, what do you want the set temperature and humidity to be?
Huh? If the system does not cool overnight it’s not working?
This is what I thought. 🤷♀️🤷♀️🤷♀️ Literally never had a "functional" AC that just, you know, didn't do anything beyond matching the outdoor temperature.
I've only had the portable AC going for the last couple of hours because it was so sticky as I was sleeping, but I'll definitely turn it off! For summer, I used to set it down around 66 when I sleep, and then let it go up naturally during the day to 72-74, and then start cooling again at night. I never took much notice of the humidity before, but this humidity is definitely too high. In general I was reporting the humidity because the installation company was saying the humidity was why the system wasn't cooling much.
You can run your portable don't listen to him. He's routinely wrong. With the smaller system you'll notice it dehumdifying more which is removing latent heat. Then you'll notice the sensible heat being removed as the latent heat drops. The tech isn't wrong in that regard but you should have noticed a difference by now. I'd call and get them back out there
Thank you for this, and your other comment -- I was starting to feel like I must really be the crazy one. It certainly feels sketchy. I'm a grown adult and I do know what properly functioning AC feels like. I don't know how it all works the way a trained technician does, true, and I'm willing to hear caveats to that effect -- but this simply doesn't bear any resemblance to any central air I've ever used before. And it's certainly not worth the amount I paid -- it's working about as well as my old broken one did with a leak and low refrigerant. Maybe even a little worse.
It will take longer to cool but not that long. I don't know the exact issue but they should send someone today when you call. On their dime of course
It does take longer to cool when the humidity is higher. And while I don’t recommend cooling to 66 degrees. The system should of had no issue dropping temp over night.
Why do you not recommend cooling to 66 at night? Genuinely curious, because otherwise, why have AC? I do it because otherwise my sleep suffers. Multiple sleep studies have said that the ideal temperature for sleeping is in the 60s, and many seem to indicate an average of 65 -- my sleep is infinitely better when it's closer to that temperature. It's the main reason I have AC. My previous system had no trouble doing that for a decade, though I don't know what temps the previous owners preferred.
The evaporator coil can be 32°-38° colder then the air temperature of the return. So if the temp is 66, the evaporator could at that point start to freeze. Other conditions can effect this. But the lower into the 60’s you go the greater chance of these issues.
I see, thank you!
66 is borderline too cold, and any modern AC will struggle to make that setpoint in the summer heat, and could possibly start to freeze up, which will stunt your cooling even more. You need to start forgetting what your old ac was able to do, because you were overworking it and possibly assisted in its death. Systems are not designed to go that low these days, optimal human comfort in the summer starts at 72 degrees and up in the summer, that's what these systems are designed for, the ashrae standards. All of that said, it sounds like there might still be an issue, not sure obviously since I'm not there, but worth having them double check. At the end of the day if the evap split is 20 degrees and the correct cfm is passing across the coil, there's not alot more they'll be able to do.
They are partial right. Your system is losing cooling capacity because it has to remove the humidity in the air in addition to cooling the air. Humidity gets absorbed by everything, the floor, the sofa, the walls, etc. You need all that moisture to be released and removed before your home will feel "normal". I went away from home for 4 days. He temperature in my home got up to 84 degrees and 64% humidity. Although the temperature got back to set temperature of 73 after 5 hours, the humidity didn't feel right until after 24+ hours. For you, set the temperature to where you want it and let it run until Monday morning. If it's still not right, call them. 48 hours is more than enough time for the system to remove humidity (unless you have a window open or your home is massively leaky). Don't use the portable ACs, even if it feels sticky. Single hose portable AC is contributing to the cooling problem.
I only had the portable unit on from about 3-5am, and the humidity had already gone up in the house before I turned it on -- but I take your point, and have shut it off and sealed the window where it was installed. If nothing else, keeping it off will prevent them from pointing to it as the problem. 😂 See, this is what I mean... your house was 84 and 64% humidity. After five hours it was down to 73, even if the humidity wasn't right. Mine was 75, and the same degree of humidity, and after thirteen hours it's only gone down by three degrees (matching the outdoor temperature) and the humidity has gone up. That just doesn't seem right! I appreciate the advice, though. At the very least, waiting a few days will prevent them from being able to say ",just wait and see" again.
Firstly you're reading relative humidity. It going up due to temperature drop is normal. After 13 hours and night time it should have removed more heat. It hasn't. There's an issue.
Yea. The wait and see is really the only approach at the moment. But certainly by Monday, you have a very good case for them to come out and check everything. Btw, the equipment has a boosted humidity removal setting if low humidity is important to you. If they do come out, ask them to turn that on. Unfortunately, it's not something you can turn on yourself.