A/C problem

[Bird_Freak]

My buddy has a problem with his Dometic a/c unit. This is a older unit. It may run all day and then just shut's off and comes right back on and continues to do this. It acts like the power shuts off and comes right back. I replaced the thermostat because I didn't understand what he was telling me to start with and no change.
Any Idea's what will cause this?

[Bird_Freak]

Thanks guy's. I will check it all out when I can get back up there.

[enblethen]

That helps.
That age probably has a circuit board. could have a loose connecting on circuit board.

[Bird_Freak]

enblethen wrote:
What is the approximate age of the unit?
Should also have some information under the interior unit.

2003

[enblethen]

What is the approximate age of the unit?
Should also have some information under the interior unit.

[Bird_Freak]

enblethen wrote:
Get the model number of his Dometic A/C unit.

He is 70 miles from me and can't get on the roof and has no paper work.

[enblethen]

Get the model number of his Dometic A/C unit.

[Hondavalk]

i know with mine the unit will have a pause like when the blower automatically changes speeds. been doing that for the eleven years ive owned it. the hotter it is the more it cycles

[pianotuna]

I am in a unit that does that. I don't think there is any power shedding--but that could be it too.

[Coach-man]

I agree it is a voltage issue! The thermostat operates on DC voltage which operates a relay. The relay turns on/off the A/C unit. Low voltage will let the relay release prematurely and then it try’s to turn back on. It could also be a faulty relay. Looks like you need a qualified A/C technician to check all the components.

[enblethen]

Could be issue with the power if it is a low voltage thermostat. Low voltage control should have a transformer and could have an auto resetting circuit breaker.
make and model of original and replacement thermostat.