A/C Trouble

[bcoop]

Was working fine yesterday, woke up at 6 am because I was too hot to sleep.

Blower fan runs, condensing unit fan runs. No ice build up or condensation at all on the evaporator coil. Neither the start, nor run capacitor is bulging. No burned up, or loose connections. Compressor housing is hot to the touch. After monitoring with the access panel off, compressor starts up for about two seconds, then kicks off. Can see liquid in the sight glass, but obviously wouldn't be able to see bubbles since the system isn't running. I don't have gauges to put on it, or a volt meter, so I'm checking the best way I can before having to call a service company.

System is a Carrier, compressor is a Copeland Compliant Scroll rated for 3.5 tons. Serial number indicates it was built in December of 2000.

Now, the capacitor controls both the condensing fan and the compressor. So common sense tells me it's not a capacitor problem. Is this correct?

Granted, I'm no pro at this, but deductive reasoning tells me that there could be a voltage problem, causing the thermal overload to shut down the compressor. Or, the only other logical (to me) problem is a locked up compressor. Any advice or guidance anyone can give, I'd greatly appreciate. I'm very mechanical, but tools are limited. And if it's a bad compressor, I don't have a choice but to call a service company and get raped.

[CJ-95GT]

Have you tried flipping the breaker to reset it?

[bcoop]

Have you tried flipping the breaker to reset it?

I haven't done it with that intent, but I've had the breakers off a couple times while checking connections, etc. Still the same problem every time I flip ten back on.

[bcoop]

I'll be damned. Run cap tested bad. I'll provide more info in a bit for the rest of the DIY crowd.

[Vertnut]

I'll be damned. Run cap tested bad. I'll provide more info in a bit for the rest of the DIY crowd.

Buy a good one. Some of those cheapies won't last a season.

I can recommend "Papapepper's Heat and A/C Service" if you need some help. I hear he offers a $100 discount, too. ;-)

[bcoop]

Buy a good one. Some of those cheapies won't last a season.

I can recommend "Papapepper's Heat and A/C Service" if you need some help. I hear he offers a $100 discount, too. ;-)

I bought a gentech, as it's all I could get my hands on today. This one is rated at 440, and the last one was 330 IIRC.

So here is the rundown. I talked to a friend's Dad who is a tech. Over the phone, he ruled out the contactor, because the condensing unit fan was on. he said if the contactor was bad, the fan at the CU wouldn't come on. But since it was, it was getting 240v all the way across. He said it's likely the run capacitor, because the compressor would start but wouldn't stay running. My system has two capacitors. Both of them are run capacitors. One looked like two d cell batteries side by side. The other was a large cylindrical capacitor with three terminal blocks on it. I ha a blue wire going to the hermetic terminal, nothing going to the fan terminal (because of the separate fan cap), and two yellow wires and a black wire going to the common terminal. Both caps are metal. He said you won't always have a start cap separate from therun cap. Also, start caps are plastic. Metal caps are run caps. The large one was for the compressor, the small one was for the fan motor.


Just wanted to post this here in case anyone else had a system like mine. All the googling I did, I never once ran across someone posting about an issue where the fan was on, but the compressor wasn't running.

[jw33]

Yeah just replaced my cap last week. I picked up two at Grainger in case a neighbor has one go out or this one only lasts a year or two. $39.xx out the door for the pair and it takes 15 minutes of labor and I've never even messed with the a/c caps before.

[miketyler]

Sounds like fan had been replaced and came with its own caps leaving a vacant post on the large cap.

[Lason]

Yeah and talk about a scam, you cant get those at home depot or lowes. Only option is shops who only sell to contractors. Last time I had a cap go out I located a few of them but no one would sell to me.

[UserX]

Yeah and talk about a scam, you cant get those at home depot or lowes. Only option is shops who only sell to contractors. Last time I had a cap go out I located a few of them but no one would sell to me.

I had the same problem, everyone wanted to charge for a service call and labor. "We don't sell parts only", f that. A $30-$50 part turns into $300.

I finally found Locke Supply in Denton and picked one up, back in business 10 minutes later.

[jw33]

Any Grainger will carry them on the shelf for $15-20.

[JasonRR]

I'm currently having a very similar issue, fyi.

Woke up to a hot house, saw nothing obviously wrong with the outside unit and found the breaker tripped. I reset it, and it'll trip again within 2-6hrs (usually).

I have a friend who's family runs an HVAC copmany that I very much trust, and he replaced the capacitor ($30) for me, but that didn't fix the problem. He decided that we should replace the breaker just to be sure that wasn't bad, and he found that both wires going into the breaker were completely loose, not secured by the screws. Replaced the breaker ($20ish, I think), but still have the problem.

After consulting a few of his experts, they each independently said that my compressor was likely getting low voltage due to the wires not being installed properly and that my compressor is going out. Nice.

So now I've got them looking for a compatible compressor, or I get to upgrade to an entire new, more efficient, $6k system. Someone buy my Harley!!

[bcoop]

I'm currently having a very similar issue, fyi.

Woke up to a hot house, saw nothing obviously wrong with the outside unit and found the breaker tripped. I reset it, and it'll trip again within 2-6hrs (usually).

I have a friend who's family runs an HVAC copmany that I very much trust, and he replaced the capacitor ($30) for me, but that didn't fix the problem. He decided that we should replace the breaker just to be sure that wasn't bad, and he found that both wires going into the breaker were completely loose, not secured by the screws. Replaced the breaker ($20ish, I think), but still have the problem.

After consulting a few of his experts, they each independently said that my compressor was likely getting low voltage due to the wires not being installed properly and that my compressor is going out. Nice.

So now I've got them looking for a compatible compressor, or I get to upgrade to an entire new, more efficient, $6k system. Someone buy my Harley!!

That's pretty much what I found when I was researching the other day. Breaker tripping is bad wiring, or bad compressor. Good luck. Still probably looking at $1500+ just for that.

[JasonRR]

Right...if I can find one that runs with the older coolant that my system needs. Then I've gotta re-fill it with coolant, which is several hundred alone if I recall.

I checked with State Farm and they told me I was fucked.

[mustngacman]

You can still buy what they call is a dry condensor. It is new but it will not have any freon in it. I would amp out the system you have now and see what that shows. It could be short cycling and cause the breaker to trip.