HVAC units intermittently stop and restart

“Indoor air handler is showing code 02 when running. When trying to heat the compressor will turn on for a minute or so and then shut off. The air handler keeps running and the system never reaches temperature to shut off thermostat as it’s just blowing lukewarm air. Any ideas or help is appreciated! submitted by /u/Downtown_Alfalfa_313 [link] [comments]”

“I have an approximately 18-year-old Carrier 58STA/58STX gas furnace with the thermostat fan set to AUTO. The furnace heats the house effectively, with strong airflow. However, during a heating cycle, after the thermostat first displays the setpoint temperature, the blower completely stops for approximately 30 seconds. It then resumes and continues heating until the thermostat displays one degree above the setpoint. The furnace then shuts down normally, with the blower running briefly af”

“I have a Guardian heat pump, recently it has stopped running for air conditioning. It will start up like it’s going to turn on then almost immediately stop. So only my air handler is circulating air. I’ve reset the breakers and set the thermostat very low. Any advice? submitted by /u/dark_sar-chasm [link] [comments]”

“Hi everyone. A few weeks ago my AC stopped blowing air. Was fine when it wasn’t 100 degrees every day the past week. I’ve had control board issues in the past (had to have it replaced twice in the past 3 years). Taking a look at it to see if maybe the HVAC person wired it correctly or maybe a completely different issue altogether. I hear what I believe is the blower motor kick on and it hums but the fan doesn’t spin. The blades can be moved freely by hand with no resistance. Attached is what the”

“Older Goodman furnace. Put a new blower motor on old one had failed, tested ac, was a little low added some 22, tested the heat, kicked off after 5 minutes I checked with my temp gauge to make sure the plenum safety wasn’t just weak and it is actually getting that hot I turned blower speed all the way up air flow feels correct. Still kicking out,I check the heat exchanger no holes anywhere, I checked bottom of evap coil not dirty enough to cause it to get hot enough to kick the safety I believe”

“Furnace is a Maytag M5SB086A AW with Beckett 7505 internals. B ACKGROUND: this is installed in a double-wide that I rent and I have no information concerning servicing, maintenance, anything other than it says it was installed in 2014. Going by everything else I have experienced concerning this rental, I would be nearly 100% sure it has been neglected, no oil filter changes, no checkups, adjustments, etc. If it helps I have no idea what nozzle size it has installed and there is no visible shut o”

“My AC blows air but it’s room temperature air. I noticed the fan was not spinning so I replaced the capacitor and it would not spin. I pressed this button and it starts running but as soon as I stop the fan stops. Any ideas on what it could be? Or this something I should go ahead and call an HVAC company for? submitted by /u/Aggressive-Rub-20 [link] [comments]”

“cleaned out gas furnace burners and gentle cleaning of flame sensor. ecm variable speed motor in squirrel cage in back of ifc board. gently went though 4 inch filter housing and with vacuum attachment slowly cleaned squirrel cage slats. Now no blower motor function. r to c on board good 24 v and checked all limits and they are closed. Gentle cleaning of squirrel cage induce miniscule back emf and blow out module??? sorry i attempted to clean it. Will do manual testing of motor and module to see”

“When I would run my unit when the thermostat called for cooling the fan would come on, the compressor would buzz for a second and then stop. Had a tech come out check voltage, capacitor, contactor and all that, finally tells me compressor is shot. Fast forward to today. Tech returns installed new condenser. Same exact issue. Waiting tomorrow now for a “senior tech” to be available. Please I need help thank you submitted by /u/No-Question598 [link] [comments]”

“AC been having some issue. After the unit is on past 4-5 hours. The outdoor compressor will stop every 5-30 mins randomly. Then it will come back on for 5-30 mins randomly. While the outdoor compressor stop working the indoor is still pumping air but warm. I'm not sure what is causing it . I have hire 3 different technician to come over and check all of them say everything is normal. The worst part is the issue will occur at midnight. Then when the sun rise. Probably after 7-9am the issue wi”

“I live in Florida and we have one of those giant metal box units outside for our ac. I woke and the air is blowing but not cold. When I go outside the unit is humming but the big fan is not turning. The unit is only a few years old. submitted by /u/Ready-Stuff-8213 [link] [comments]”

“I just got a new AC system, single stage 2 ton Daikin, and mid cycle, it slows down for second like it’s going to stop then speeds up again and will do this again a few minutes later and then maybe again a few minutes later - I hear this inside when it’s running. Just will be running then slow down for second then speed back up and run normally again. It’s working fine as far as cooling but since it’s brand new, this worries me a bit. Any way this could be normal? Model number: DC4SEA2410AA &#32”

“He recently had the flex ducts sealed because apparently they were not sealed properly and were leaking. Anyway, I have noticed that the systems runs for about 5 minutes than turns off 5 min or so later is turns on again only runs for a few than turns off again. Hvac company came out a supervisor came out and spent 3 hours checking the airhandler inside and outside. He found that the refrigerant was low try to see if there was a leak with some appliance. Said no leak refill it. Told me to call i”

“Like title says, a few weeks back we lost power for about 5 hours. After it came back on I could audibly hear the condenser kick on from inside. Did some googling and I found out about hard starting etc, I happened to have a spare cap so I threw that in just to see if it was the issue but it’s still doing it. What’s the recommendation from here? submitted by /u/Scrumpuddle [link] [comments]”

“The system is still cooling. Blower fan, outdoor unit are both functioning normally and cycling on and off as commanded by the thermostat. But this relay is clicking nonstop near the blower motor. submitted by /u/EMDoesShit [link] [comments]”

“I have a 10year old York LX Series TM9M gas furnace. It’s starting to get cold up north so I turned it back on for the season. It has worked fine for us for 4-ish years we have lived in the house and had been derived twice since 2022 for general maintenance. I turn the furnace on at the thermostat stat and it shows ‘heat on’ status. The flame kicks on fine and runs for about 20 seconds and then turns off. It will cycle like this until it stops. I took out the flame sensor and cleaned it and repl”

“My air handler has recently been kicking on and off randomly when the system is not calling for cooling. I had a local HVAC company come out and look at it and they said they couldn’t find anything wrong with the system. It doesn’t do this all the time. The system cools just fine and I have no issues with the fan turning off during a cooling cycle. I do have a Nest thermostat and I went through all of the settings to make sure I don’t have anything weird set up. Air handler is a 2010 trane 4TEC3”

“Old Ultra V Tech 80 furnace with SV9520 SmartValve. My parents' furnace has been doing what the title says for a few weeks. Someone came out and of course it wouldn't do it then but he disconnected the G wire and said if it still does it then it's probably the smart valve and quoted $1700 to replace. Before doing that I decided to try a few things first. - replaced thermostat with another I had, still happened - disconnected W and G wires to eliminate thermostat wiring, still happene”

“Hi everyone, I am a homeowner and fairly new to these things. So yesterday my AC stopped blowing cool air. I tried to troubleshoot it. The condenser fan worked fine, but was blowing cold air, the refrigerant lines were ambient temperature. Then I tested the capacitor and found that it was shot. Changed it to a new one with the same specs and now the fan is running and restarting every few seconds and still not blowing cold air indoor If my guess is correct I must have wired it incorrectly and an”

“My AC/Furnace doesn’t kick on. Thermostat is working fine. I had a a tech look at the unit and he said he wasn’t getting any power to it. Turns out the main fuse (20 Amp) in the furnace blew. So I replaced it. The new fuse hasn’t blown, but neither my actual AC fan or the furnace fan kicks on. And none of my breakers are tripped. I turned the thermostat off auto and the fan still wouldn’t kick on. I checked everything. The wiring, made sure the panels were on right, etc. The ONLY thing I can thi”

“Hello, I just bought a home with this heat pump unit. I tried to turn on AC, I could see the compressor and outdoor fan turns on, but the blower fan doesn't. I can rotate the blower fan wheel freely so it's not binding. I took the N and L contactors off to measure voltage, and got 250vac on them. As I plug them back in, the blower turns on but only for a second and died again. I checked voltage from C to the speed taps. I got: C-T1 (orange wire): 25vac C-T2 (red wire) : 10vac From my und”

“Unit stoped cooling overnight. Everything runs in the attic and outside unit. I thought it might be the capacitor which ive swpped on the second unit before. This downstairs unit has an extra capacitor which i found out is a start capacitor and noticed it hd some burned wires. I ordered another and replaced ot but when i turned the unit on it started smoking immediately. Can i run the unit without it? The second upstairs outdoor unit doesn't have one. Or what else could be the problem?”

“Our 20ish year old AC has been turning off immediately after it kicks on—it goes on and off several times and then (usually) stays on but is really loud. The fan is moving fine and we already replaced the capacitor. Any ideas what it could be? submitted by /u/Fantastic_Koala3874 [link] [comments]”

“AC unit working on and off. I have reset the thermostat and checked the breakers. I did find these breakers on the unit itself. These would be tripped correct? Just want to check before I go mess with something. submitted by /u/Bloc_13 [link] [comments]”

“I have a split AC chinese generic brand (LD or LTD). Every 10-15 mins or so, it stops working, inside it flashes "auto" sign for 10 seconds and outside the compressor and fan stop. After these 10 seconds, the inside unit starts again but the compressor does not and it just blows uncooled air until a few minutes later the compressor kicks back on and the cycle repeats. I cleaned the entire thing inside, outside was very dusty and i washed it and the coolant pressure is okay. I brought a”

“In the middle of the day the ac starts to kick on and ramp up, but before it gets fully going it kicks off and then starts the process of trying to restart again. I can usually turn it on in the am and it works. Also, when it’s acting up I can run the fan for 5 minutes and then turn on the ac and it works normal. Unit outside continues to run even when it’s doing its intermitted start/stop. Lights on the board flash normal until it fails then turns red. No code. Ac guys say it’s either the blowe”