Compressor started fine but when adjusting the temp on the thermostat it was off for one second and then asked to come back on. "Grunted" ("burped") once and then nothing. Waited at time-same result, waited longer, hours, same result. Breaker is good. Any ideas appreciated.

Time to check the capacitors. They are located in a small compartment accessed by removing the roof-top cover and then the electrical compartment cover.

What is the voltage? How much does voltage sag during the attempted start? How old?Yes the start capacitor might be shot. Not sure how to test... maybe just replace.

Haven't detected a pull down on the voltage by the lights dimming. Not at the camper until later in the week. The A/C was used quite a bit during the preceeding week without a problem....just this mistake to try to restart so quickly. It is eight years old, never had any trouble, not even recharge needed.

What's the Make and Model?Assuming it has one fan motor, it'll have Run Capacitors for Fan and Compressor. Total of two Run Cap's. They're called Run, but the motors won't start without one or with a failed one. They may be separate or in a common case.It may (probably does...) have a Start Assist made up of another capacitor and some form of switching device.If you can get up there and take pix of Manufacturer's Model/Serial/Rating Label, Wiring Diagram, and Capacitors, please do, and please post them.

Might as well get a hard-start cap kit. Replace remaining capacitors. They do not last forever. A replacement run cap is way cheaper than a replacement fan condenser/evaporator motor.

A/C Grunts once and won't start | Good Sam Community

14 Replies

j-d
Explorer II
Aug 22, 2016
Good on YOU! It's clearly worth it to try the capacitor before calling a tech or scrapping the A/C. The capacitors aren't the only thing that goes wrong, of course, but sure worth the minimal cost and effort to rule out the possibility.
08Surveyor33
Explorer
Aug 22, 2016
Well, I replaced the motor start capacitor ($10.00) and it fired right up. All's well that ends well. Wife feels better.
charwan
Explorer
Aug 15, 2016
08Surveyor33 wrote:
I resisted telling the world that my wife did it. She feels bad.

It wasn't her fault. That thermostat should have had a delay built in. Its not supposed to have started back up until the fluids equalize and turn back to vapor. Everyone here has done it before and the thermostat saves us.
08Surveyor33
Explorer
Aug 15, 2016
I resisted telling the world that my wife did it. She feels bad.
charwan
Explorer
Aug 15, 2016
MEXICOWANDERER wrote:
Might as well get a hard-start cap kit. Replace remaining capacitors. They do not last forever. A replacement run cap is way cheaper than a replacement fan condenser/evaporator motor.

Most of the time when a start capacitor goes bad it will swell up and you can see it.

Someone needs to say that dirty word, "Compressor".
charwan
Explorer
Aug 15, 2016
08Surveyor33 wrote:
Compressor started fine but when adjusting the temp on the thermostat it was off for one second and then asked to come back on. "Grunted" ("burped") once and then nothing. Waited at time-same result, waited longer, hours, same result. Breaker is good. Any ideas appreciated.

Not good when one restarts right back up. Should have been a pause in there.
ScottG
Nomad
Aug 15, 2016
donn0128 wrote:
Lots of advise, so I have to add mine. Go up on the roof, take the cover off, and try to spin the fan by hand. Mine was frozen about three years ago. Broke it free by hand and used lots of WD40. Still working great.

I have to do this every spring.
donn0128
Explorer II
Aug 15, 2016
Lots of advise, so I have to add mine. Go up on the roof, take the cover off, and try to spin the fan by hand. Mine was frozen about three years ago. Broke it free by hand and used lots of WD40. Still working great.
time2roll
Nomad
Aug 15, 2016
The lights will not dim as they are on 12v power.
MEXICOWANDERER
Explorer
Aug 15, 2016
Might as well get a hard-start cap kit. Replace remaining capacitors. They do not last forever. A replacement run cap is way cheaper than a replacement fan condenser/evaporator motor.