Basement AC problems

[Vectra 04]

AC doesnt communicate with the thermostat . I have another thermostat that I tried and it didnt make any difference . Blank screen .
Any ideas ? thanks

 

[Henry J Fate]

Be sure you have 12 volt (battery) power to the thermostat. The control circuit is 12 volts. Be sure you have good house batteries that are charged/you are plugged into shore power.

Thermostat 12 volt power is many times wired through the propane furnace. The same 12 volt circuit will be used to control the air conditioning.

Those are a few things to think about. When you have a moment, post what you are using for equipment and include your specific RV build.

 

[Vectra 04]

I have a 04 Winnebago vectra with basement AC . I have power to the AC but it wont feed the thermostat ,its blank screen ,checked the fuse in thermostat, tried a diff thermostat it didnt work either.

 

[Vectra 04]

Be sure you have 12 volt (battery) power to the thermostat. The control circuit is 12 volts. Be sure you have good house batteries that are charged/you are plugged into shore power.

Thermostat 12 volt power is many times wired through the propane furnace. The same 12 volt circuit will be used to control the air conditioning.

Those are a few things to think about. When you have a moment, post what you are using for equipment and include your specific RV build.

winnebago04 Vectra basement air

 

[Vectra 04]

winnebago04 Vectra basement air

 

[emiddleb]

You have a couple banks of 12v push-style fuses, might check to see if any of those have popped. On my floorplan there is a bank on the bed platform (behind a panel with the 120v breakers) and a couple sets in the outside bay right under the driver's seat.

 

[Henry J Fate]

I have a 04 Winnebago vectra with basement AC . I have power to the AC but it wont feed the thermostat ,its blank screen ,checked the fuse in thermostat, tried a diff thermostat it didnt work either.

120 volt power to the air conditioner will not power the thermostat. The thermostat is powered from your 12 volt system (batteries & converter/inverter charger) Look for a tripped 12 volt breaker or possibly a 12 volt fuse. Many times the 12 volt air conditioning control circuit is powered from the propane furnace circuit. Good Luck

 

[Vectra 04]

120 volt power to the air conditioner will not power the thermostat. The thermostat is powered from your 12 volt system (batteries & converter/inverter charger) Look for a tripped 12 volt breaker or possibly a 12 volt fuse. Many times the 12 volt air conditioning control circuit is powered from the propane furnace circuit. Good Luck

Thanks will try to find about ready to call service

 

[John Canfield]

Look at the truth table I made for the Coleman-Mach thermostat and check for 12V from red/white to blue/white wires.

 

[Vectra 04]

Look at the truth table I made for the Coleman-Mach thermostat and check for 12V from red/white to blue/white wires.

Thanks John we are on the road now and will work on it when we get to Little Rock. Thank god its not hot !

 

[Ray-IN]

While using John's chart, check each 'stat connection (both ends) for continuity. These are low voltage connections and it doesn't take much corrosion to insulate the connection. I use a pencil eraser to clean such contacts. Then again it may simply be a 12V breaker popped out.

 

[John Canfield]

Indeed. Also pay close attention to my Note 1 near the bottom of that web page.

 

[Vectra 04]

Thanks for all the heip we now have AC and the wife is happy ! The form and Johns site have been of great help over the years . Service call was going to cost three hundred dollars ,so you can see what this form saved me !

 

[John Canfield]

So what was the problem?

 

[Vectra 04]

Damaged wire to circuit breaker.

 

[John Canfield]

Very good, thanks for the report.