Compressor Wiring Shorting To Ground?

[RoughDobermann]

Hi All: Last week here in Denver, my house experienced two brownouts of about one second each within about ten seconds of each other. I didn't think much of it until a few hours later when I realized that it was getting hot in the house. I checked the supply air and, gulp, it wasn't cool. Ran downstairs and the temp on the thermostat was 80 and the fan was running. Went outside and the fan on the compressor wasn't spinning and it was making a screeching noise.

Ran back inside and turned off the A/C. Ran back outside and turned the breaker off.

Had a tech come out yesterday, and he reported that the compressor wiring was shorting to ground and would need to be replaced.

So, my questions:

1) Can a brownout cause this damage, or did it just happen to fail at that exact time?

2) He gave me an estimate to replace the compressor, which gave me sticker shock. I see that pricing is not to be discussed here, but I'd really like to know what the ballpark should be.

Thanks guys!

[Refer-Madness]

Call around and get a few more estimates then compare the bids. As far as I know, even "ballpark" pricing isn't allowed.

[RoughDobermann]

Call around and get a few more estimates then compare the bids. As far as I know, even "ballpark" pricing isn't allowed.

That is the plan, yes. I'd like to get at least four bids. Can you or anyone else recommend HVAC firms in the Denver-area (Highlands Ranch, specifically)?

[chayced]

I think the better question is did the compressor grounding cause the brownouts. If it was only your house that experienced the brownouts then it was probably the compressor drawing massive current as it grounded. Compressor change out is very expensive and if done wrong can lead to compressor failure again in a few months. Good luck!

[RoughDobermann]

I think the better question is did the compressor grounding cause the brownouts. If it was only your house that experienced the brownouts then it was probably the compressor drawing massive current as it grounded. Compressor change out is very expensive and if done wrong can lead to compressor failure again in a few months. Good luck!

No, it wasn't just my house. Xcel had a transformer catch on fire in the neighborhood. I called them and they acknowledged their problem. I hope to be able to claim the replacement through them.

[gasser65]

Most of the time, you are better off replacing the entire outside unit. That way you have all new parts at least "outside". Just replacing the compressor you usually get only a one year warranty on just the compressor. If you replace the complete unit, you get approx. 5 - 10 year warranty on parts depending on the brand of unit. Be sure whoever you get to do the replacement really does a good job cleaning up the refigerant lines and installs filter driers on both suction and liquid lines. Proper cleanup on a burnout like this is crucial.

[sktn77a]

A brownout wouldn't cause this. But electrical faults like this could have originated from a surge which could cause a short to ground. On balance though, I think the two are probably unrelated (unfortunately).

[nick muniz]

Most of the time, you are better off replacing the entire outside unit. That way you have all new parts at least "outside". Just replacing the compressor you usually get only a one year warranty on just the compressor. If you replace the complete unit, you get approx. 5 - 10 year warranty on parts depending on the brand of unit. Be sure whoever you get to do the replacement really does a good job cleaning up the refigerant lines and installs filter driers on both suction and liquid lines. Proper cleanup on a burnout like this is crucial.

I had a customer reimbursed by pwr co for a cond replacement and some electronics but it was a blown transformer near his house.

[glockdoc]

Why did the fan stop running? Was it because of a low voltage caused by the short? Or did a dead fan motor cause the compressor to overheat. You might want to invest in a second opinion before condemning the equipment.

[yorktek37]

SOme brands have a no fault warranty that if you replace the indoor coil also they will replace the entire condensing unit if the compressor fails under warranty. I know nordyne does this. I have put in a few of their units and they did real good. Not bad for the money. Plus you are better off replacing the coil also since its never good to mix match. Always wondered why people used Aspen coils since they don't make entire systems. Or even worse ,,, Summit. Keep it all the same Mfg and it will be alot better in the long run. Check on the no fault replacement warranty.

[Ti Llaves]

A brownout is a temporary interruption of power service in which the electric power is reduced, rather than being cut as is the case with a blackout. Lights may flicker and dim during a brownout, and the event also often wreaks havoc with electrical appliances such as computers. One could consider a brownout the opposite of a power surge, an electrical event in which a sudden burst of power enters the system.

There are a wide ranges of causes for brownouts. Just like blackouts, overloads on the electrical system can trigger a brownout, as the generating facility is unable to provide enough power. It can also occur when events such as storms disrupt the distribution grid, or when there are other problems in the system. Brownouts can last for a few seconds or a few hours, depending on the type of brownout and how quickly a power utility can get full power running again. This condition can cause compressor damage in HVAC systems.

[Willserve]

Why did the fan stop running? Was it because of a low voltage caused by the short? Or did a dead fan motor cause the compressor to overheat. You might want to invest in a second opinion before condemning the equipment.

I'm with Gdoc, if the fan is not turning that compressor is going to scream. Rapid changes in power will smoke a capacitor in a heart beat. Since u are getting other quotes have them verify that the compressor is in fact shorted. Most of the compressors I have found shorted to ground trip the breaker faster than you can reset it. Good luck.

[RoughDobermann]

I'm with Gdoc, if the fan is not turning that compressor is going to scream. Rapid changes in power will smoke a capacitor in a heart beat. Since u are getting other quotes have them verify that the compressor is in fact shorted. Most of the compressors I have found shorted to ground trip the breaker faster than you can reset it. Good luck.

Yes, if I turn the breaker back on, it trips almost instantly.

[Ti Llaves]

I'm with Gdoc, if the fan is not turning that compressor is going to scream. Rapid changes in power will smoke a capacitor in a heart beat. Since u are getting other quotes have them verify that the compressor is in fact shorted. Most of the compressors I have found shorted to ground trip the breaker faster than you can reset it. Good luck.
Good point!

[Ti Llaves]

Yes, if I turn the breaker back on, it trips almost instantly.
You should still find out were the short in the circuit is located, before condimming the unit. By the way how old is your unit? May be a good time to update your equipment both indoor and outdoor unit's.

[Refer-Madness]

That is the plan, yes. I'd like to get at least four bids. Can you or anyone else recommend HVAC firms in the Denver-area (Highlands Ranch, specifically)?Saunders & Johnson is a good company for resi work (I'm on the commercial end of the field so no resi for me, yay!), in fact it was that company that made me choose this career. I hired them to install A/C in my own home before I was a tech and they did it right, so professional it was inspirational. I changed careers within 1 year. They still have the same owner AFIK so I doubt that has changed.

Look at the bright side, it wont even break 65 here today and it looks like that will hold for the 5 days or so! Isn't this JULY!?!?!?

[Willserve]

Went outside and the fan on the compressor wasn't spinning and it was making a screeching noise.

Ran back inside and turned off the A/C. Ran back outside and turned the breaker off.



Way I understood it fan wasn't spinning the only thing left to make screeching noise is compressor, which they do when fan hasn't been running. Did you turn breaker off or was it already tripped? Just wondering.