Best Guess on A/C Problem

[Wayne Boatwright]

When I got home from work at 5:30 today, the house seemed a bit warmer than usual. We keep it set at 80° F. when we're away, then crank it down to 75° F. when I get home. It was 85° F. when I arrived. It was 107° F. here in Arizona today, but this unit has always been able to maintain any temperature we set, even with outside temps as high as 117° F.

The air handler inside the house was working, as was the fan at the top of the compressor unit outside. I checked all the circuit breakers both inside on the main panel, and on the outside box leading to the compressor unit, and unless there's an internal breaker or fuse inside the compresor unit, I'm betting on a bad compressor or sudden loss of coolant. We have not noticed any gradual decline in cooling.

The system is not yet two years old, so I'm sure it's still under warranty. Given that, I don't want to mess with it.

I'm waiting until my other half gets home to dig up the papers on the unit so that we can call for repair.

Can anyone think of a different problem than what I've outlined?

TIA

[bfrabel]

y. =A0

Try washing out the fins in the outdoor condensing unit with a garden hose, they are probably packed with dirt. It doesn't take much to affect the unit's performance when it gets as hot as you say.

Good luck.

[Wayne Boatwright]

On Mon 11 Aug 2008 07:37:31p, Ralph Mowery told us...

Then we have a big problem. The air from the vents is 85, the return air is 85, which is the same as the room temperature. I have opened the air handler where we change the filters and there is no ice on the coils. The coils also seem to be about the same temperature as the room temperature.

[Edwin Pawlowski]

The condenser fan is running, but what about the compressor? It may be kicked out for some reason, such as low refrigerant, or something in the electrical circuit. Any resets on it? Even a power drop during the day can cause problems sometimes.

[Ralph Mowery]

You failed to give the temperature coming out of the vents and also the return air temperature. If the difference is around 20 deg. IF you probably have no problem. If less than 15 deg or the same, then you have a big problem . If the refrigerant is low , the airhandler could ice up and you would have very low air flow or maybe no air flow coming out of the vents.

[CJT]

I would cycle the big breakers that control the compressor. Sometimes they can trip but that fact won't be evident. Turn them all the way to "off," wait a few seconds, then put them back on and see if the compressor starts.

I assume your thermostat is calling for cooling?

[mm]

Yes, there are several cutout devices in the compressor box, for low pressure, for high pressure, and a couple other things. I think one or more has a reset button**, and the others reset when the problem is solved. Plus there could be a freon leak (which eventually would cause low pressure, but would impede cooling even before then).

**Pressing the reset button started up a friend's AC, but it only worked for a day or so. I never heard what the real problem was.

[Wayne Boatwright]

On Mon 11 Aug 2008 06:54:07p, Edwin Pawlowski told us...

I don't believe the compressor is running, but haven't yet opened up the housing. I was afraidof voiding the warranty. There is nothing visible from outside that would indicate a reset. I hope to have a service man out tomorrow. I think at this point I've checked everyting else I know to check.

[Wayne Boatwright]

On Mon 11 Aug 2008 07:58:47p, CJT told us...

I will retry both of the breakers again.

Yes.

[Wayne Boatwright]

On Mon 11 Aug 2008 09:38:53p, mm told us...

I don't think we have a freon leak, as there has been no drop in cooling capacity right up until we left for work this morning.

If I can't get a service man out early tomorrow, I may open it up and take a look for a reset button.

Thanks!

[Stormin Mormon]

Good advice. It only takes a little dust to clog the fins, and keep the heat in.

[Stormin Mormon]

Since the indoor coils are same temp as room, you have no cooling going on. You mentioned the outdoor unit fan is running. So, it sounds like either the compressor isn't running, or there isn't enough freon to be useful. Or the outdoor coils are packed with dust.

[Stormin Mormon]

Compressor not running can cause those symptoms. Many times, such a problem is a simple electrical repair. Bad part, that's relatively easy to repair.

You mention the system being two years old. May also be under warranty.

[Stormin Mormon]

Rheem units often have a reset button for high pressure. If you push the reset and the machine restarts, it still needs service.

[Chris Hill]

Probably a bad capacitor. If you're lucky they will have one on the truck. If not, they'll probably be able to find one and install it in the same day.

[Puddin' Man]

You should be able to *hear* the compressor if it's running. It's a much deeper sound than the fan.

If you have a fused shut-off box, check for 220 volts (both legs) coming out the box whilst unit is running. Could have a bad or blown fuse.

P

"I Ain't Blind, I Just Don't Wanna See" - the title of a tune by Little Joe Blue, maybe 1966

[mm]

I forget, but I don't *think* the fan would run if either leg were dead.

[Stormin Mormon]

The fan is also 220 volts, but much lower amperage. And uses a separate capacitor.

[Wayne Boatwright]

On Tue 12 Aug 2008 05:55:25p, Chris Hill told us...

The unit has now been repaired. It was a bad starting motor in the compressor. Compressor was replaced under warranty. Labor $$$$$.

[Stormin Mormon]

Thanks for the report. Nice to know it got fixed, and covered at least partly by warranty.