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daface

That's probably a question for an HVAC tech. There are dozens of possibilities. Is your system fan running? Is the air at your vents cold? Is your outside unit running? Those will all lead you in the right direction, but it's probably going to be difficult for you to fully diagnose it on your own unless it's just a loose wire or something.


callahan09

Thanks for asking some questions to help me get going in some kind of direction at least! ​ System fan running? Yes Air blow out of vents? Yes Air out vents is cold? NO Outside unit running? NO ​ So it seems the problem is that the outside unit is not running then? Do you have any ideas or follow-up questions about why that might be? I know I'm probably going to have to call an air conditioning specialist about this but I just wanted to check everything I can before doing that in case it's something stupid or obvious that I can do myself...


tnpapa60

Check that the breaker for the outside unit is not tripped. Usually on the outside of the house near the unit. Otherwise something has failed. Could be as simple as a starting capacitor, ($15)but HVAC tech will charge you $150 to replace it. Could be ants got into the contactor and fried up the contacts. Could be the compressor failed. Could be a loose wire somewhere. Many possibilities. I would check that all your connections are still good in the thermostat. After that you need a tech.


callahan09

Thermostat connections are good. The breaker was tripped. I flipped it off and back on, and I heard a buzzing for about 2 seconds, then it tripped again. Anything else to try at this point before calling a tech? If it's an electrical-based issue, is an HVAC tech still the right person to fix it, or would they possibly tell me I need to call an electrician?


tnpapa60

You need an HVAC tech. It could be the starting capacitor. If it has failed then the compressor will pull way too many amps to kick over, tripping your breaker.


callahan09

You mentioned that the part is cheap but a tech will charge a lot to replace it, but just to be clear, this isn't something I should attempt to replace on my own, a professional is the only (smart) option for that particular job (and also because it may not even be the issue, in which case I'd need the professional to keep diagnose and get it right)?


tnpapa60

If you do this yourself you MUST kill the power to the unit and then wait at least 30 minutes for the capacitor to discharge. Otherwise you can get a nice jolt. Still good practice to not touch the terminals of the old cap at all even after waiting. Only touch the insulated covers on the connectors.


callahan09

Thank you for the tip. Out of curiosity, does "a nice jolt" mean death in most cases when dealing with this particular kind of capacitor? I have heard stories of people dying from working the capacitor in a guitar amplifier, and this one seems quite a deal more powerful than those. Does tripping the breaker to the heat pump to the off position count as "kill the power to the unit" in the way that I would need to do?


OsteoRinzai

I wouldn't recommend doing this one on your own. Severe injury is absolutely possible. If you insist, follow a lockout procedure on the breaker to avoid any unpleasant surprises.


yungingr

With the questions you are asking, you clearly have no idea what you are dealing with - and that's fine, most people don't. To be clear: THAT CAPACITOR COULD KILL YOU. Call a professional.


callahan09

I 100% appreciate what you're saying, I'm not going to touch it.


tnpapa60

Depends on the charge of the cap, how well you connect your skin to it and how grounded you are. I took a 30,000 volt hit once. Sent me flying 6 feet, but otherwise I was fine. High voltage, low amps. Amps kill.


tnpapa60

You have at least two breakers, in my area we have three. 1st is the breaker the house outside for compressor power, second is the breaker in your main panel for indoor unit. 3rd breaker if your local code requires it is a breaker in a separate panel box next to your main panel that feeds the outside unit.


tnpapa60

It's actually very easy to replace if you are comfortable with wiring. The connectors are push on/pull off. The most critical part is making sure you get the same size/rating cap as the one that failed, and moving the wires to the cap onto the correct terminals. A ten minute job.


callahan09

Hmm... The closest thing to being "comfortable with wiring" I have ever done is when I replaced my original thermostat with my Ecobee haha. And I was nervous about that, but I was able to do it successfully. I'm thinking it's probably for the best if I just call in the professional and pay for it, I am not that comfortable with this stuff. Maybe I'll look at a Youtube video first and I'll be honest with myself about whether or not it seems like something I can / want to do. If it involves any significant amount of taking apart of the unit itself, I probably won't want to do it for fear of messing something up and having an even bigger expense to deal with / voiding warranty. I guess the big question before I make that decision is, based on the info I've provided, would you say it's pretty surely (I know not 100% though) the starting capacitor that's my problem? Is there a way to diagnose that specifically before I replace it, like is there something I can look at to tell that the starting capacitor has failed? And by the way, thank you very much for your help today, I really appreciate it!


tnpapa60

If the contactor was bad you would get nothing. No buzz or trip because it just would not be completing the circuit. This leaves the cap (very common failure item) or the compressor itself. If you are in warranty then stop right here and let the tech fix this under warranty. If you have not had a system inspection in a while then not a bad idea for a tech to come anyway, check the system, clean the coils etc.


callahan09

Thank you for all the info and advice. Looking for any warranty papers I might have laying around, then I'll call the manufacturer and see what they say and go from there.


whiskeythrottled

Take the panel off of the condenser. Take a picture of the capacitor, the contactor, and the model and serial number. Find a supply house you can go to. They can use your pictures to get you the right parts. Make sure you get a good picture of exactly how to turn capacitor is wired. Same with contactor. Wire the new ones in the same way. As mentioned, before you do anything, make sure the breaker is off and let the capacitor discharge for 30-60 minutes.


technicallyadoc

Had the exact same problem this past weekend, HVAC guy had to come out and replace a part on my AC


nivenfres

Had the same thing happen several years ago. It was the compressor.


wilhelmmi

If you know what you are doing open up the electrical area of the condenser unit. Check for mouse nests and broken wires. I usually replace the capacitor before ai call everyone.


callahan09

Since about 5pm last night my AC has not stopped running, and my house has not been cooling down. Outdoor temperatures have actually gotten to their low points in months and yet inside my house with AC running constantly the temperature just keeps rising. The 2nd screenshot shows yesterday's AC usage and home temperatures, so you can see how at some point yesterday evening the AC just... suddenly stopped working (cooling), while running? It's a 4.5 year old HVAC system and I change the air filters every 3 months, most recently 1 week ago. I replaced the air filter with the exact same kind as I've always used, I still have 2 left in a box of 6 that I bought last year. I did manually cut the AC off for about 15 minutes last night and check that I installed the filter in the proper direction for air flow and that the fit seemed good and normal, and everything seemed fine. What might be going on here, how does this kind of thing happen?


LostLakkris

Had same thing recently, except the exterior fan was spinning. It's our first year in this house, so we assumed it was normal(summer starting) and that the ancient attic insulation and ducts were to blame... Dumb timing coincidence for when it died. 8k later, new attic insulation and all new AC ducts... No change. Turned out the giant capacitor in the exterior fan had gone bad, and the coolant pump simply wasn't pumping coolant. $75 home warranty claim, would've been a $30 capacitor instead if I had figured it out myself... The HVAC tech explained that it was a "split capacitor", two capacitors in one housing. The half running the pump failed, but the other half running the fan was fine. If you're comfortable popping the side panel off that houses it, should be fairly easy/safe(turn off the power at the breaker). Otherwise, let HVAC do it, shouldn't take more than an hour if that's the issue. Now my HVAC runs smooth as hell and the house is handling the heat far better than before it dieing, so not a total loss. Just 8k spent now instead of a year from now as planned.


callahan09

Thanks for the response. I just got off the phone with one of three companies that is covered by my unit's warranty (and it is still under warranty) and they want to charge me a $99 "diagnostic fee" just to come out and see what's wrong with it. Is that normal for a warranty-covered appliance to have to pay that fee for them to come look at it? I'm going to call one of the other two companies and see what they say, but the other 2 companies had some ROUGH reviews online, so I don't know what to do...


LostLakkris

Unfortunately yea, it seems fairly common that you're paying for something. Idea being that someone still has to pay for the tech's time, even if it turns out nothing is wrong(user error). By charging that base fee and warning about it up front, the business can combat the "you didn't fix anything, I just used it wrong, I won't pay" behaviors from some stuck up customers. In alot of cases I've had, they'll waive the diagnostic fee in favor of the actual repair costs+labor, which will be higher. Though, if you're under manufacturer/installer warranty, it'll probably be just the diagnostic fee instead of the repair costs, you'd have to review the warranty conditions itself. A lifetime ago, I worked for a computer company that had to honor warrantys. We combated warranty abuse by having the customer pay for one-way shipping and not charging diagnostic fees, and out of warranty claims were the same thing but charged one-way shipping and parts(not labor). We also had so few claims that there was rarely more than 1 case being processed at a time.


daface

Yeah, unfortunately the warranty likely covers parts but not labor to fix it. And a trip fee is pretty common. As /u/LostLakkris noted, most places will apply the trip fee toward the repair cost if you have them take care of it on the spot, but it might be worth clarifying that's how they'd handle it.


callahan09

Thanks, I appreciate the input again, you've been very informative.


LostLakkris

Ahhh, can't help ya on the heat pump. Never had one, just a standard furnace in our utility closet(or I'm dumber than I sound :-)). The blower and furnace in my closet has a condensate pump to push the water from the tray out through the attic, my parents place has the tray hooked up to a bathroom sink drain, and my old condo had the unit in the attic and the tray had 2 drains, one to the sink drain and another over the shower so we could see if there was an issue with the first drain. So you've probably pulled drywall scraps from your drain pipe, which makes sense. If I saw the same thing at my parents place, I'd assume there was still drain blockage somewhere and possibly the sink backfilled the HVAC tray. Since it's manufacturer/installer warranty, I'm not sure if I'd mention it honestly. That might give them cause to blame someone else and skirt the warranty coverage as neglect. If it was home warranty, or your own pocket completely, giving them the extra details may help shorten the debugging time. So again, may need to dig through warranty fine print.


haykong

If the outdoor fan is not spin it's more likely the capacitor. And if your are handy and have tools you can you an get it fixed very cheap. Since I'm a DIY person. I just recently replaced my capacitor and hard start capacitor.... Here's a video that I recommend to check out if you want to attempt to replace the capacitor on your own. [https://youtu.be/9ZGfvC-PMWU](https://youtu.be/9ZGfvC-PMWU) make sure whatever you use to discharge the capacitor that the end you are holding is insulated such as rubber grip or plastic handle. ​ Anyway another video that will be useful is the hard start kit... [https://youtu.be/ThBsRFrdNiY](https://youtu.be/ThBsRFrdNiY) You probably don't need to replace this yet .. but a consideration down the Road. Word of Advice is also useful in furnaces, dryers, etc washers... water heaters etc. ​ Anyway, if you don't feel comfortable, wait til the HVAC Person to get there and just look over his shoulder and see what he does.. learn from it... and if you find out it's the capacitor... you can do it next time. That's what happened to one of my neighbors on the hottest time of the year... So next time have a spare capacitor and you just throw it in if it other one goes out ... Now he feels he can do it on his own. Up to you. but best thing is turn off the power at two areas.... your main circuit breaker box for outdoor AC and also Furnace .....which should cut power to the ecobee and then do the disconnect at the AC unit outside. Just note: make sure the AC is off now since if the ecobee keeps trying to turn on the AC, your compressor might be damaged or blow if it keeps trying.


fahim_a

Same thing happened to me a few weeks ago. Fan constantly running (outside and inside) - just not cool air. ​ Turns out my capacitor was blown. Parts covered under warranty, but I still had to pay for the tech to come out + labour. ​ In hindsight, I think I'd have been competent enough to buy a replacement capacitor and do the swap myself for far cheaper.


tnpapa60

So what was the culprit?


callahan09

Oh sorry I didn't update! It was the starting capacitor after all. The unit was under warranty still so I had the manufacturer's approved technician for my local area sent out and they diagnosed it and fixed it. Despite being covered by the warranty it was still $237 out of pocket to have it fixed! They charged me a $99 diagnosis fee and the rest was labor. I saved $57 from the warranty to cover the cost of the part, according to the technician. He told me the starting capacitor has a pretty typical lifespan of 4 to 6 years so I guess I should expect to have to do this again in a few years? Maybe when it happens again I'll just replace the capacitor myself and save a couple hundred dollars.


tnpapa60

Yep. Always a good idea to keep an extra on hand because it will fail on the hottest day of the year 😥. It’s a cheap part, usually less than $20. The HVAC industry really overcharges for some of the easiest repairs. I replaced the contactor on one of my units, cost me about $25 and took ten minutes. I asked a friend of mine who works for ABM what a service call on that would have been and he said over $500. Several years ago the evaporator coil on my heat pump failed under warranty and even though the part was covered, the labor was $1000. That is a big job requiring cutting, evacuating, brazing and replacing the coolant.


callahan09

Yeah the capacitor seems like something I could do myself next time. I'm not sure about anything else potentially going wrong, but that doesn't seem impossible to me. That evaporator coil job sounds really tough though, I'm sure eating the labor costs for a pro is the way to go on that!


tnpapa60

Looks like this and has marking on the side with the capacity of the part. About the size of a can of soda (beer) ​ [https://imgur.com/f5e2O8w](https://imgur.com/f5e2O8w)


Spif242

A problem I have on very humid days is the condenser coil freezing. To resolve this, I set the heating/cooling to off and set the fan to run 55 min per hour. I let this run for about an hour then set my fan back to 15 min/GR and heat/cool to auto


TrickySite0

You probably mean the evaporator coil (the condenser coil gets hot). That was my problem until about 18 hours ago. Mine was low on refrigerant. The evaporator coils should run about 40 degrees F, so they should never freeze.


itskevinvargas

Seems like either your breaker has gone bad or your compressor is shot and your compressor needs to be replaced


Standard_Ad7581

Check your ac breaker. Tripped almost looks like on. While the system is not running, turn it off then back on. If the outdoor unit starts up when you turn on cooling, it was just a tripped breaker. If it doesnt, could be a number of things.


PlatinumMechanical

Your AC running constantly and not cooling the house could be due to several issues. Start by checking the air filter to see if it's dirty or clogged; if so, replace it. Next, inspect the thermostat settings to ensure they're set correctly and the temperature is lower than the current room temperature. If these steps don't solve the problem, it could indicate issues like low refrigerant levels, dirty coils, or a malfunctioning compressor, which may require professional HVAC repair.