No 12V to T-Stat

[jgavin]

Does anyone know where the RH/RC wire to 12 Volt connection cap is located? I have an open somewhere. I did a bypass to test & got my AC to work but would like to find the original to repair if someone can help.

Thanks,

[SteveC7010]

Originally Posted by jgavin

Does anyone know where the RH/RC wire to 12 Volt connection cap is located? I have an open somewhere. I did a bypass to test & got my AC to work but would like to find the original to repair if someone can help.

Thanks,

Do you have one of the newer Dometic digital thermostats?

[hankpage]

My thermostat is powered by AA battery all the time ... no 12v. to power it.

Red wire is 12v + Blue is ground.

The following chart shows the different electrical connections made by the thermostat during
operation. The chart below assumes12VDC(+) is supplied to thermostat Red wire “R” and that
12VDC(-) or ground is supplied to the Blue wire “B” at all times.
Thermostat Operations
Internal 12VDC(+) Connections Made

Cool Mode Selected On Low Fan
Red “R” to Yellow “Y” and Gray “GL”

Cool Mode Selected On High Fan
Red “R” to Yellow “Y” and Green “GH”

Heat Mode Selected On Any Fan Speed
(Note: Furnace blower operates independently
from sequencer or time delay in furnace)
Red “R” to White “W”

Fan Only Selected (Hi-Fan Only)
Red “R” to Green “GH

Check your main power center for a blown or loose fuse

[SteveC7010]

According to my files, the standard analog Dometic thermostat is wired as follows:

Fan..........Orange or Tan
Cool.........Yellow
Ground......Black or Green
Furnace.....White
High Fan....Blue
+7.5vdc.....Red

This thermostat looks like this:


I am not sure where the Red gets its 7.5vdc. I would look at the furnace first to see if it's there. If not, it will be in the A/C. According to my install manuals, both the furnace and the A/C are capable of providing the operating voltage for the thermostat.

Important note: IF YOUR UNIT HAS ONE OF THE NEW DOMETIC DIGITAL THERMOSTATS, DISREGARD THE ABOVE INFO. The new Dometic digital control system uses a proprietary signalling system between the thermostat and the appliances. It's uses a cable similar to a phone or computer data cable and it's NOT tapable in the way that we've all worked with the analog thermostats for so many years.