Originally Posted by Skippy38
Odd question living in FL but the cool weather this morning has me wondering. I have a red switch on my control panel that is labeled "HTR". I know I have to turn the propane on, when I flip the switch I can hear the furnace trying to light. After it lights is that enough or do I have to control it with the thermostat? I have a main thermostat for the A/C on the wall also and when I flip it to "Heat" I can here it trying to light also. Do I have to operate both or is either one sufficient to operate the furnace?
I read where you got the furnace figured out. As Don stated, the switch on the control panel is for the propane/DSI side of your water heater. When you flipped that switch, you actually heard the DSI making sparks to ignite the propane for the water heater.
This link below may help, especially if you have the Suburban brand water heater:
Suburban's electric switch and much more