09-02-2018, 07:18 AM
Jon,
When I built a prototype alternate board I discovered that the delay function is in the thermostat logic. The tstat sends separate signals for the the evap fan, cond fan, and compressors. The one situation that would require some noodling is how to get the cond and evap fans to run at two different speeds depending on whether one or two compressors were running. I ended up using six relays instead of four to get high and lo fan speeds. I need to do some research and see if the tstat power supply can power the relays directly.
Also to Guy's comment. House systems are 24V, and of course much more common. They may not have been a 12V tstat with the functions Newell wanted available when your coach was built, so it would have been pretty easy to run a transformer and use a 24V volt system.
When I built a prototype alternate board I discovered that the delay function is in the thermostat logic. The tstat sends separate signals for the the evap fan, cond fan, and compressors. The one situation that would require some noodling is how to get the cond and evap fans to run at two different speeds depending on whether one or two compressors were running. I ended up using six relays instead of four to get high and lo fan speeds. I need to do some research and see if the tstat power supply can power the relays directly.
Also to Guy's comment. House systems are 24V, and of course much more common. They may not have been a 12V tstat with the functions Newell wanted available when your coach was built, so it would have been pretty easy to run a transformer and use a 24V volt system.
Richard and Rhonda Entrekin
99 Newell, 512
Maverick Hybrid Toad
Inverness, FL (when we're home
)