Trane AC not cooling after being turned to heat mode for a couple days

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I'm not quite sure even what the relay looks like but I watched him testing things with a voltometer and he showed me everything was working correctly. Got the fan to turn on and it made a loud noise that I usually associate with the compressor, but he said the compressor wasn't coming on. I don't really trust him that much. He keeps trying to push replacing the outside unit with some off brand. I might have to try harder to get the original installer to actually respond. Too bad he's never in his office in town bc I'd go there and meet him face to face. He's the only other option. New guy balked at the idea of me buying another Trane unit from the authorized dealer and having him install it.

If he's willing to risk setting my house on fire just to make a sale by selling me an incompatible outside unit then I don't want to deal with him, but I'll see what he says. I might have to see if I can find a Trane dealer in TX at this rate. At least the sales tax would be lower and if the unit weighs less than 5k I can carry it in the back of my truck.
 
Your truck has a 2 1/2 ton payload?
 
I would guess that your outside unit would not weigh more than 500 lbs. 2 guys usually install these things with no issues and ONE person can easily move it around on a pad for specific positioning. PROBABLY more like ~300 lbs.. but I haven't weighed one.
Steve
 
Thanks sadavis80. My truck can carry 1,559lbs in the bed. Haven't heard back from the most recent AC repair guy. I guess he probably doesn't want to do the job anymore. Either that or he's waiting until I get more info for him. I'm still going to try to contact the original installer. Maybe he might be interested if I say I want to buy something from him. Not sure if he can still get Trane brand. Know he gets Ruud or something like that.
 
Hi there! It's good that you've already checked the filters and poured bleach down the condensate line, but there may be something wrong with either the thermostat or the compressor.
It's the compressor. It died. Thermostat works fine and we even replaced it.

Trane gave me some contacts for places that sell their units & today I FINALLY got someone to call back. I gave him the model #s and he said the good news is that they made newer condensers compatible with my air handler and that they can get it today and install it Monday. With installation it will be over $5700 (probably not including sales tax which will be over $570 if they go by the in-town rate). Can't remember what the rate is out in the sticks, but we usually get charged in town rates. It would only be like 8% tax without the town's tax.

It's expensive but I'll be happy to get a new AC unit. The compressor would be over $4k so a whole new unit with a 10 year warranty sounds better. I'm waiting for a callback to give my address.
 
It started heating instead of cooling again so I shut it off for awhile and then changed both filters and poured bleach down the condensate line. It is now cooling again. But I started thinking about something. The intake vent in my brother's room-- which is in a weird alcove just behind where one of the doors to his room opens-- is hard to get to. The door to his room won't stay shut and he has an old ladder from a loft bed in there that props against the door to hold it closed. The room is full of trash and I have to pull plastic bags and bottles off of the vent because they stick to it via suction.
The AC installers from 2010 were going to make the main intake vent in the hallway larger (24"x24") until they realized there was a 2nd vent in the bedroom. They left it with two 21"x21" intake vents. My friend suggested moving the intake vent from my brother's room and putting it next to the one in the hallway (assuming there are no studs in the way).

Is this feasible? Or do the vents have to be directly underneath the air handler?

Crappy sketch of current situation: (NOT to scale)1681439055478.png
Proposed changes:
1681439236632.png
Is this feasible?
It would make changing the vents much easier and would eliminate problems of air being sucked out of my brother's disgusting room.
Any thoughts?
 
Well, its frelled again.
Power went out for several hours & when it came back on the AC was blowing super HOT instead of cold. Pipes that are normally cold were hot. It will not cool. I've poured bleach down the condensate line, changed filters, reset breaker, let the AC sit off for several hours after doing so. No luck and we are boiling.
 
Well, its frelled again.
Power went out for several hours & when it came back on the AC was blowing super HOT instead of cold. Pipes that are normally cold were hot. It will not cool. I've poured bleach down the condensate line, changed filters, reset breaker, let the AC sit off for several hours after doing so. No luck and we are boiling.
Maybe the condenser is bad (if freon levels are ok)
 
IMO, the most likely culprit is the reversing switch.. either the relay that activates it or the switch itself.
Suggest you try cycling it several times between heat and cooling but probably best to give it 3-5 minutes in each mode - don't just bounce back and forth.
Steve
 
IMO, the most likely culprit is the reversing switch.. either the relay that activates it or the switch itself.
Suggest you try cycling it several times between heat and cooling but probably best to give it 3-5 minutes in each mode - don't just bounce back and forth.
Steve
You'll need to reset the Temp in each mode to make sure the system actually tries to change the switch.
 
The compressor/condenser are brand new. Less than 6 months. I went outside after turning cooling back on and checked that the compressor is running. It sounds like it is and the fan is going. Fan is blowing cold air out the top of the AC.

It's been having issues where it wasn't cooling to specified temp.

Hmm.. To reset I just go and change the temperatures and switch to each mode? I will try that. Thank you.

Edit: aborted the 20min test bc it just got hotter & hotter-- up to 90. Now trying it in heat mode. But its not heating or doing anything bc its already hot. Might set it at a higher temp for a short time to see if it does anything.

2nd Edit: resetting temps and swapping between modes did nothing. It's now up to 92.
 
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The compressor/condenser are brand new. Less than 6 months. I went outside after turning cooling back on and checked that the compressor is running. It sounds like it is and the fan is going. Fan is blowing cold air out the top of the AC.

It's been having issues where it wasn't cooling to specified temp.

Hmm.. To reset I just go and change the temperatures and switch to each mode? I will try that. Thank you.

Edit: aborted the 20min test bc it just got hotter & hotter-- up to 90. Now trying it in heat mode. But its not heating or doing anything bc its already hot. Might set it at a higher temp for a short time to see if it does anything.

2nd Edit: resetting temps and swapping between modes did nothing. It's now up to 92.
Maybe a freon line broke?
 
It's possible. The seller called me back and said it could be that the solenoid for the reversing valve got fried but could also be that the thermostat settings got changed. Said if I can find a way to access the installer menu, I can check to make sure it is on O terminal and sov/reversing is set to energized for cooling. Still trying to find that out. I've got the Honeywell Home RTH9585WF thermostat.
 
You need to call whomever installed the new compressor/outside unit and see what they have to say. Did they TEST the unit after installation? Seems that all this should have been tested after/during the installation.
 
If the power went out, and now the A/C doesn't turn on properly, I would first suspect a line surge, which will fry circuit boards. One power outage that occurred at my house, caused my TV and my stereo to both get fried.
 
It sounds to me like you still have the EXACT same problem you had with the old unit that you replaced. SOMETHING, that DID NOT get replaced "must?" be the problem.. unless it worked perfectly AFTER the new installation and has now failed again. I can't follow the time line of all this for certain.
When you test, you should be able to tell within 5 minutes whether the system is ATTEMPTING to change the temperature in the 'correct' direction. Waiting around for the temperature to 'get to' whatever you set it at, is not a good way to go at it. The air out of your vents should start changing pretty quickly if the system is operating correctly. minutes, not hours. It may still take the house a much longer time to get there, but you don't have to wait THAT long to see if it's working at all.
 
Thanks, Shan. There is no Menu button on this one. I found that same page.
I get this that has some very detailed stuff under system settings that I don't know the answers to the stuff.
1693241909021.png
Greg said it could be that the board that tells the solonoid to control the reversing switch could have been fried. He said there are some available that he can get if that is the case.

sadavis80, it was working fine after they did the install. They ran it for 30min to make sure it was cooling and that pressure in the coolant thing stayed consistent. But it is heating instead of cooling so the reversing switch is not working for some reason-- either board, solonoid valve, or incorrect setting in thermostat.

Greg, the seller, is trying to find info for me and said to let him no if we can't get it working and he'll send someone out tomorrow.
 
So, there's a circuit board in the condenser unit:
1693268613983.png1693268654484.png
An orange wire in the molex connector was loose. It wasn't touching the pin.

By default the condenser is set to blow hot. When the panel was being removed it jostled something and caused the reversing valve to switch. But the wire had to be pushed back in to make everything work properly.
 
Wow. Fantastic that you found that loose connection AND fixed it! Glad to hear it's finally fixed!
 
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