HVAC Techs Battling Failing Systems

“I have 3 zones/thermostats in my house. Why might cold air be blowing in a zone with a thermostat that is off? My AC system occasionally behaves weirdly in this way. Zone A's thermostat would have a set temperature while Zone B's mode is off, but Zone B would be blowing cold air at times. I'm not very knowledgeable on AC systems with all their nuances. Any information is helpful and appreciated, thank you. submitted by /u/iPhillice [link] [comments]”

“Morning folks. Had some storms roll through all day yesterday and we experienced a power surge that I believe fried something in our AC unit. The outside unit is spinning fine, no odd sounds or hums. I shut the breaker off for 30 minutes for a hard reset and it didn't help anything. The units kick on and the fans blow but there's no cold air. I just pulled into work and didn't think to take pictures before I left home. Whaddya thinks going on here? Capacitor? If so, do the capacitors”

“Hey everyone, I live in a manufactured home and every year the condensate line ends up freezing / backing up, sometimes to the point of causing the furnace to stop running (I think due to a pressure switch being tripped?) I have went in the crawlspace and the only solution I see is to possibly run the condensate line into the main sewer line as opposed to directly outside as it is currently ran. I'm not sure who to call or how to tackle this issue due to the limited space between the sewer l”

“Hi all. Central AC question….. What does it mean if the expansion valve is freezing up within 5 minutes of turning on the system? Coil and filter are clean and there’s good airflow over the coil. I had to have the refrigerant topped off at the beginning of this season. Does this indicate a refrigerant leak somewhere or could it be the expansion valve going bust? submitted by /u/fasthackem1 [link] [comments]”

“My ac unit drain was apparently clogged landlord came over unclogged it, hooked drain pipe back up under the furnace, after it worked fine for a day or 2 then stopped cooling blowing warmer air out and the outside unit was not running. I unplugged the pvc drain pipe under the furnace and let it leaks into a bowl for the time being so I can have a/c. Plugged it back in went to work came home and now even when I unplugged the drain line the water wasn’t coming out anymore and air still blowing war”

“I was changing the air filter and it was dented and the filter got caught. Part of the cardboard ripped off and fell in. I cant get it out. The ac has still been on for like 3+ hours. Do I need to call maintenance? Is there a risk of fire? I cant find definitive answers online and I live in a building where the management is pretty uninvolved so don't want to ask for assistance if its not needed. But also don't want to neglect this if its an issue. Can someone help and let me know what t”

“What causes this? Is there a fix I can do to get it up and running? My house is miserable tonight. :( submitted by /u/Altruistic-Mango-847 [link] [comments]”

“I have a new to me house that has this old humidifier connected between the hot/cold air plenum and the cold air return. The water line isn't connected and the humidistat has also been disconnected. I plan on removing the takeoff from the plenum and the humidifier box from th cold air return and covering with a new piece of tin/tape etc. I guess I'm wondering how detrimental/how it will affect the system. It's basically straight feedback from the plenum to the cold air return and I c”

“We have an 18-year old HVAC system that’s had some issues over the past year and a half. Yesterday morning, the indoor unit completely shut off but the compressor outside was still running so we just shut the system down and called someone. The unit runs on R-410A refrigerant as well. Turns out, our capacitor on the indoor unit completely fried and the blower motor went as well. The motor has been making a weird clanking/squeaking noise for the past week. Our HVAC guy isn’t pushing us one way ou”

“I went up to replace the air filter because the AC had stopped blowing cold and we thought it might be an issue. As far as I could tell, looking through the machine, there was ice. Someone's advice was to turn the AC off but leave the fan on. We did, and cold, legit cold air, kept coming through for like a good couple of hours. Is this just leftover cool air in the ducts? Is this air being cooled by the ice on the coils? I can't figure it out, but the with the fan on but AC off, the hous”

“Long story incoming, I'm just so confused. We bought our house just under a year ago. We have a mini split (N80MSN, R4A4S and EVD4X are all the model numbers) that was functioning great the whole time. Husband and I like it cold and keep it 69 during the day, 68 at night. Never had an issue, swap out the filter monthly, everything seemed fine. 3 months ago I noticed the line outside was DUMPING water and was frozen closest to the outdoor fan, and the AC was just running 24/7 but barely cooli”

“My air isn't blowing out cold and there's little force coming from the vents. Im not sure if its frozen or not? If so, what do I do? Please help. submitted by /u/Far_Foundation1582 [link] [comments]”

“Our AC is not pushing out cold air like it did yesterday. We have changed the batteries on the thermostat, changed the filter, and let the ac stay off for 4.5 hours last night. Does anyone have advice on what the issue might be or suggestionsfor something that I would be able to check myself. Our house is 80 degrees at night and even hotter during the day. submitted by /u/Remarkable-Bug4552 [link] [comments]”

“Hey everyone, my AC unit went out yesterday. It was still circulating, but not blowing cold air. I ended up replacing the capacitor with a Titan HD part from Home Depot. That lasted about 1 day. So, not sure if I got a bad capacitor from Home Depot and I should attempt to replace that again. Or if there's a much larger problem. Any insights is appreciated. submitted by /u/edddduhhhh [link] [comments]”

“System Specs: Outdoor Unit: ICP/Carrier 2.5-Ton Condenser (Model: R5A5S30AKAWA, R-454B) Indoor Unit: Day & Night Air Handler / Coil Installed: March 2026 (Pre-charged) Background & Timeline: 1. System was rarely run during spring. 2. 3 weeks ago, started major home renovations (floors, drywall/paint, popcorn ceilings). 3. Tradesmen ran the AC at 68°–70°F with exterior doors propped open. 4. AC was then shut off for a week during final flooring install. 5. Deep cleaned the house and pulle”

“Should the second PVC from the left be capped? I believe the first one should be. And the one on the far right should be uncapped. Im trying to figure out why im getting this persistent condensation on the middle part of my unit and im wondering if there is some kind of internal air restriction. submitted by /u/heyitspriddy [link] [comments]”

“Okay. This is my 4th time here. 3 months ago I noticed my AC wasn't cooling super well. It was running 24/7 and still above the set temp. I posted here, somebody pointed out that the pipe outside was frozen which could mean low freon. Had a tech come out, he agreed on low freon, said there was a leak, and in 30 minutes was in and out and it was supposedly fixed. He never went into the attic to check for attic leaks, just to clarify. 31 days after he visited, it happened again. I did what you”

“Our Wall unit is completely frozen, from the top to the bottom of the vents. Filters are frozen into the ice. At the time of posting, AC hasn’t work in 4 days to thaw… but clearly that’s not working. Any idea what could possibly trigger this? submitted by /u/atcha_boii [link] [comments]”

“My AC unit stopped cooling. I cleaned and vacuum the outside unit. I also vacuumed out the drain. The shop vac was filled with that goo. When I put back in the outside shut off there was no power. There's power at the main breaker, and at the unit in the attic. My question long story short is there a fuse or switch I'm not stopping power from going outside? submitted by /u/like_if_KD_ruinedit [link] [comments]”

“About a month ago the power went out and when it came back on the thermostat was dead. I changed the batteries, but the air wouldn't kick on. I went to the roof to check it out and as soon as I touched the drain pipe it turned on. Every now and then the ac will shut off and I'll go to the roof, hit it, and it'll turn back on. What is the issue. submitted by /u/No-Violinist5217 [link] [comments]”

“3 days ago, I noticed my AC was at 71° with the thermostat set to 68°. I checked the outdoor unit and found the compressor frozen. I shut it off, changed the dirty filter, cleared the ice off the compressor with water, checked the attic pan/drain (both good), and restarted it. It cooled fine for about 24 hours before struggling again. I called HVAC and was told the attic coils may not have fully defrosted, so I ran the fan only for 8 hours. After restarting, it struggled to keep up but eventuall”

“So I rent and our ac went out so it’s currently 80 in our home with a baby, landlord said he’s not calling an emergency hvac to come out we’ll have to wait till tomorrow. The motor or whatever it is inside the outside unit and the line set running off of it and into the house is frozen solid. The fan will run but I get nothing inside the house. I checked the air return and vacuumed it but I don’t know what else to do, TIA submitted by /u/Novel_Ad1567 [link] [comments]”

“In the evenings, I noticed the house temperature actually increasing. I went outside and noticed this line has a lot of ice on it, even under the foam. I did replace the filter, so it’s brand new. A one man band hvac tech said the system is fine, but I know he didn’t t get in the attic to check the unit so I am not sure on his opinion….should I have another reputable company check it? Ideas? Tia submitted by /u/Elpadre83 [link] [comments]”

“I believe I have a positive pressure hvac. Do I need to put a cap on the 2 white caps to prevent cold air from releasing? submitted by /u/TitanColaberry [link] [comments]”

“We've been having a heat wave upwards of 106 recently and during the hotter days the ac unit stops blowing cold air. I checked the outdoor unit and didnt hear any noise and saw the fan wasnt moving either. This typically lasts until the sun goes down and then it starts working again only to fail again around 4-6pm. What can I do to fix this issue? submitted by /u/Main_Conclusion_6714 [link] [comments]”

“My A/C is in my garage and in humid weather it collects condensation that drips and makes a mess. Can / should I wrap this in insulation or will that result in soggy insulation? Also, how? I only have access to 3 sides. submitted by /u/ElevatorFlatulator [link] [comments]”

“Had a 27 year old 4 ton system running fine last week. This week outdoor unit iced up like hell and air temp coming out of the registers was equal to the outdoor temp. Tech said he could recharge but due to the age of the unit it could be 600-700 bones (Less than what I was expecting tbh). He seemed honest and gave me a several options. I opted to due a full replacement because the old unit was a bit shit, and the gas furnace was just as old. I took the 4 ton enhanced efficiency option at $12,42”

“Had no A/C for about a week. Just got a new central unit installed today. It’s set to 67 but the temp won’t go below 69. It’s been a few hours and it’s holding steady at 69. What could cause this? submitted by /u/CrueDude18 [link] [comments]”

“I moved into my new apartment a week ago and last night i noticed that the temp did not drop when the sun went down. Normally I set it to 75° during the day (I am in south texas and it was around 97° yesterday) but at night i set it between 68°-70° (nighttime temp is between 76°-82°). Last night the thermostat was set to 70° and the temp was 77° when i woke up sweating in the middle of the night and it was only 2° cooler than outside💀 I’ve never had a wall unit like this before but does this lo”

“Where the aluminum tape is, there was cold air coming out of little openings from what seems like a poor quality install with the handler. The air goes up into the air ducts in the attic. Will that make a bit of difference or am I wasting my time? submitted by /u/Marcotaco18 [link] [comments]”

“First time homeowner here so please go easy on me! My HVAC drain lines are clogged which is causing the float switch to trigger and shut my AC off for a couple of hours at a time. How should I drain the water? Bring a shop vac up to the attic and suck the water out? I’m also having trouble determine which pipe is the drain line for my AC on the outside of the house. The black pipes run to the right side of my house and there’s 2 pipes by the foundation. The white PVC pipe runs to the left side o”

“Hi all, Blower motor went out over the weekend, so I replaced the motor yesterday morning and the AC was running. Our house was very hot without AC, so I took a WHILE to catch up and cool off. The unit is 17 years old, so I was looking up how to maintain it and figured if clean the unit outside. I sprayed it with a foam AC cleaner solution and then rinsed it. The power was off and I restarted the unit within 5-10 min after rinsing. Fast forward 8-9 hours and the line from the outside unit coming”

“2 days ago, my AC was struggling. Filter was dirty and being sucked into the blower. Changed it Fan was working. Just no cold air. Looked outside, there is ice on this as well as the rest of the copper tubing on the inside. Let it thaw out, and turned AC back on. It worked wonderfully. Now AC unit is struggling again Please point me in the right directions, Im a new home owner and willing to learn how to fix all my stuff as techs can be very expensive submitted by /u/Ok_Breakfast_733”

“My house was built in April 2021, last year the compressor blew and last week 1 of the 2 zones (thermostat 2nd floor and another on 3rd floor) was struggling to reach the desired temperature. I had my HVAC guy come and checked the coolant on my system and it was all good. He then asked me what filter I use and I told him I get them at Costco, 16x25 on the 2nd floor and a 20x30 on the 3rd floor, system in attoc doesn't take a filter. HVAC guy immediately said that it's no good and to chan”

“I looked it up online, most popular answers are the filters, freezing, or capacitor. My filters are new, nothing is freezing, my fan is spinning fast, so I don’t think it’s the capacitor issue. Any other likely issues? Here is how my outside unit sounds submitted by /u/Zestyclose_Row5070 [link] [comments]”

“My hvac unit is no longer properly cooling. Currently I watched it hit 81, set at 76. Things I’ve done since Wednesday: new filter, drained the line, checked the float for condensation-bone dry as of 3 days ago, changed the capacitor, gave the unit a gentle rinse. Honeywell thermostat had been turning off for long periods of time the last 2 days. Today was a short time until I unclogged the line and it turned back on. Capacitor seems to have improved the outdoor unit itself- sounds more normal t”

“My Whirlpool thru wall air conditioner is blowing cool ( ish) air, not cold. The compressor seems to be working, and I have done the troubleshooting steps listed in the manual….unplug, reset, wait, etc…..no results. Should I just buy another unit or can it be repaired? submitted by /u/LoveableCurmudgeon73 [link] [comments]”

“AC mostly stopped working, it was still blowing out 64ish cold air when I tried to see if it was working at all Filter was dirty, so I changed it HVAC system was running I normally keep my house at 66 Google says this is not what is supposed to happen to the copper? So to let it thaw? Is that possibly true? I dont trust google much anymore submitted by /u/Ok_Breakfast_7331 [link] [comments]”

“My AC is nice and cold. I bought this condo last year and the HOA said to clear condensation line. I replace the air filter once a month even though it stays it can last up to 3 mo the. Is the thing in red the condensation line? This is what i think i should do: Turn off AC Pour 1 cup of standard kitchen or 30% vinegar in the line. Wait 30 minutes Pour 2 cups of distilled water Put cap back on and turn on AC submitted by /u/jaygut42 [link] [comments]”

“I have a five-year-old house. I live in Florida. Periodically, my air-conditioning unit stops working for several hours. Then unexpectedly it’ll start working on its own. I usually call the service people. they tell me that the water outflow has become obstructed. this will happen every several months or so. I do Use vinegar in the intake periodically. Is there any way I could stop this from happening? submitted by /u/AltruisticPickle8635 [link] [comments]”

“I went to change my filter and found that the lower 1/3 of my unit is frozen over. None of the other units in my apartment have this problem. The AC seems to still be working, but this can't be right. What's caused this, and how do I fix it? submitted by /u/Chris149ny [link] [comments]”

“I think I’ve narrowed it down to two possibilities — or I haven’t bc I have no idea what I’m talking about. 😆 AC is shutting off because there is too much water in the catch tray. And it can hold A LOT of water, I learned in my first go off shop-vac’ing it out. the condensate drain line is blocked and none of the water is going out something is broken in my machine and water is ONLY dripping out into the tray I cleared all the water in the tray and did the vinegar in the T routine. An hour late”

“I think I’ve narrowed it down to two possibilities — or I haven’t bc I have no idea what I’m talking about. 😆 AC is shutting off because there is too much water in the catch tray. And it can hold A LOT of water, I learned in my first go off shop-vac’ing it out. 1) the condensate drain line is blocked and none of the water is going out 2) something is broken in my machine and water is ONLY dripping out into the tray I cleared all the water in the tray and did the vinegar in the T routine. An hou”

“Hello! When I got home from work yesterday I realized my AC was not working. The indoor unit if blowing air however, it is not cold. The outdoor consenser unit will not start the fan and appears to be making a "Buzzing" noise when trying to start. Any ideas on where to begin troubleshooting? submitted by /u/Opposite_Twist_7312 [link] [comments]”

“Had a brand new 3 ton Goodman heat pump and air handler installed 7/29. On 8/2 noticed house couldn’t stay below 73 went outside and had significant icing. Turned system off to thaw and indoor unit leaked water so assuming those were frozen as well. Techs came out 8/3 thought they fixed a wiring issue, froze up later that day. Techs came again 8/4 and replaced txv valve, froze up again about 6 hours later. Everytime they’re here and they “fix” it they say they are getting perfect readings on all”

“R22 3 ton system. Shorted compressor.. so it was blowing ice cold . Yea it's 27 years old. I got my automotive 609. So I know a little about a/c... I know the compressor is shorted internally.(Checked windings to ground) What are my chances of getting another r22 compressor and a vac and recharge to keep the system running?. Will pay 20 bucks for a complete system assessment and a professional option that's more then, yeah you need a r32 system, cuz your shit is 27 years old.... Should I”

My air conditioner randomly stopped working so I put in a maintenance request. Maintenance came and looked at it and said the hvac guy needs to come. The hvac guy came and…

“It’s a Bryant quantum using 410a that’s at least 16 years old. It stopped blowing cold air overnight. Fan works, but no condensation on the pipe. The tech noted that the kickstart had blown, he plugged in a different one and said “it isn’t working, the compressors bad” but he tried again and it worked, we had immediate condensation. But the a couple minutes later the condensation went away and he said it’s a bad compressor that I need a new unit. I did not get the impression he was trying to pul”

“My AC stopped working, it blows air but its not cold. The outside fan spins. Is there anything I can do to keep as a DIY? I have seen changing the capacitor might get it fixed but I had a tech saying I need a new compressor. I just want to see if there's something I can do before I have to take that next step. submitted by /u/Individual-Act6564 [link] [comments]”

“When I left for work at 7 AM , the AC was working just fine. When I get back home around 4:30 PM the AC is making this weird Hissing sound and no cold air is coming out. It’s only blowing air @room Temp. Any idea what it could be. The AC guy who installed it did a huge crap job, we’ve had a couple problems with this AC unit. Had an HVAC guy come through and he said the whole installation was crap. submitted by /u/AnonymousJay23 [link] [comments]”

“Was wondering if could get some help. Used to have issues with blank thermostat, started regularly using vinegar in drain pipe cleared the issue right up. Now thermostat is functioning but outdoor unit won't cranked. Capacitor looked corroded some, changed it unit started right up. But now indoor unit just has a low airy sound it seems like its not fully powering up.. any ideas? submitted by /u/RedDotDucksauce [link] [comments]”

“Noticed the downstairs was getting warm and looked outside and the fan was not spinning. I checked the outside unit and nothing appeared frozen, so I turned off the unit and was gonna call an hvac tech. However, the next morning I tried turning it back on and it worked fine, cycling on and off normally, for about a week. Then the same thing happened, fan just stopped running. I turned it off overnight and then the next morning I turned it back on and it started right up and worked just fine for”

“Have had issues with AC every summer in the last two years now where it slowly starts to get warmer and warmer. Got it fixed at the beginning of the summer, they said there was no coolant leak or anything, and was cold air for awhile but has slowly gone back to warm air. The hissing noise never really goes away but recently has been louder with the AC trying to run. Any suggestions would be great Car is a 2007 Jeep Grand Cherokee with a 3.7L V6 submitted by /u/solarmyls [link]”

“Maintenance man says it was fine and blowing cool air when we put in an emergency request the day it started but the air coming out of the vent is barely cool and measuring at 70 degrees. The room stays measuring at 75 which is what the thermostat is set to but it stays running and struggles to maintain it and won’t go lower. He said it was the hot weather but we have had multiple hot days prior and the ac did just fine and blew cold air. The ac also runs constantly 24/7 on auto even when set to”

“So, I had a technician come out to check the freezing evaporator coil. They found a pressure differential and recommended replacing the valve inside the air handler. However, after they put the access panel back on, the AC stopped starting altogether. First they said the wiring must have been disturbed, then they said it was the transformer. Either way, I’m without AC until Monday because the warranty parts suppliers are closed for the weekend. Do you think it’s worth getting a second opinion to”

“Hi! Our brand new AC keeps freezing (2nd installation in a month, don't get me started). The first pic is the first time it happened. I turned off the AC, let it thaw. A tech came yesterday, said the pressures are good. I asked why this is happening as we just got a new (forgive me) Freeze stat (the thing that makes the thermostat stop the AC if pipes freeze). The tech said the refrigerant was too high so he took some out. He says it could be our Nest thermostat. The AC worked well for 24 ho”

“Last week we had our outside ac unit turn off and it wouldn't come back on until we cycle the breaker. Today it won't turn back on at all. I've checked the main line power, the drain line have nothing coming out, drain pan is dry, the coils are clean, and the capacitor is good. Initially thought it was the defrost control board but after checking it, the Y to C voltage was 0 and R to c was 27v but from the zone board y to transformer c was 27v. If anyone has anything else to check it”

“Hello everyone. As stated the outside unit keeps running after the inside temp has satisfied the temp setting and inside unit is off. Had an ac company come out and they changed the contactor outside. This problem is very intermittent so a few weeks later it did it again. I inspected the outdoor unit and found a wire that had rubbed and shorted to ground so I repaired that thinking he maybe that's the problem but after a few weeks it has done it again. When it does happen we turn the inside”

“For 2 years our ac has worked flawlessly in Oklahoma heat up until a week ago. Our rental company said the freon is good, capacitor is good, the clean the unit and they said everything in the attic is fine. Ac recovers overnight but warms up about 8-10 degrees during the day. Any thoughts?? submitted by /u/okcoregonfan [link] [comments]”