Testing 3 wire Dometic Thermostat
I'm having some issues with my furnace. Air is working fine but nothing happens when I turn the furnace on (exhaust fan does not kick in but the AC fan runs). I am thinking my issue is with my three-w...
Forum Discussion
C. “Furnace” - Furnace Mode
1. There are 3 fan speeds in Furnace Mode.
a. “Low”: Fan operates continuously at low speed.
b. “High”: Fan operates continuously at high speed.
c. “Auto”: Fan is Off.
?If additional indoor air circulation provided by the air conditioner is NOT desired during
Furnace Mode of operation, select “Auto” in the Fan Mode to shut the air conditioner
fan off. If “Low” or “High” is selected, the air conditioner fan will continue to operate at
selected speed.
2. In Furnace Mode system will cycle RV furnace On and Off based on room air temperature
and temperature set-point on CT thermostat. CT thermostat can be configured to operate using an On / Off differential of either 1ºF or 2ºF. This feature is programmed during the system
initialization. See “B. System Initialization” on page (3).
3. To set temperature differential, system must be Off. Press button and simultaneously
press and hold / Mode button for three seconds. Press button to toggle between “d1”
and “d2”, “d1” for 1ºF differential and “d2” for 2ºF differential.
1. There are 3 fan speeds in Furnace Mode.
a. “Low”: Fan operates continuously at low speed.
b. “High”: Fan operates continuously at high speed.
c. “Auto”: Fan is Off.
?If additional indoor air circulation provided by the air conditioner is NOT desired during
Furnace Mode of operation, select “Auto” in the Fan Mode to shut the air conditioner
fan off. If “Low” or “High” is selected, the air conditioner fan will continue to operate at
selected speed.
2. In Furnace Mode system will cycle RV furnace On and Off based on room air temperature
and temperature set-point on CT thermostat. CT thermostat can be configured to operate using an On / Off differential of either 1ºF or 2ºF. This feature is programmed during the system
initialization. See “B. System Initialization” on page (3).
3. To set temperature differential, system must be Off. Press button and simultaneously
press and hold / Mode button for three seconds. Press button to toggle between “d1”
and “d2”, “d1” for 1ºF differential and “d2” for 2ºF differential.
