Does not provide enough heat to maintain temp.
Rv furnace limit switch test.
Atwood hydro flame 8940 in a fifth wheel.
That thermo switch opens if the furnace gets too hot and shuts down the gas.
Continues this cycle until turn the stat down.
The dsi is an acronym direct spart ignition it s an electronic igniter that uses a spark ignites the gas air mix.
Troubleshooting the rv furnace.
Time delay relay used on older furnaces newer furnaces have the relay incorporated into the circuit board this relay performs two separate jobs one to handle the relatively high current needed to run the blower motor and two to allow the blower to run for 45 to 90 seconds after the thermostat is satisfied.
Tried a new limit switch.
The sail switch then sends power to the high limit temperature control.
Stays lite for about 5 seconds and then goes out lites again in about 10 seconds.
They both opened at 170f and closed at 150f.
These two switches are safety switches and they are in series which means power passes from one to the other and then to the module board which sends power to the gas valve and the igniter which.
Ordered new limit switch atwood 37022 hydro flame limit switch 190 degrees around 15 with shipping paying attention to get one with correct limit temperature and also trying to find out with rv manufacturer for no reason i decided to contact them not atwood whether it s possible to take sail switch out without taking the furnace unit out.
Any ideas on what the problem ma.
Turns on ok fan starts gas ignition occurs.
The ducts carry the heated air from the furnace to the interior of the rv.
These limit switches allow the fire box exhaust on side of trailer to get up to 405 degree.
The exhaust is an air outlet on the exterior of the rv that exhausts the gases produced during the combustion process the gases are a combination of carbon dioxide and carbon.
A limit switch is a device that s located under your furnace s supply plenum.
Took both switches to a test lab and tested them.
Once the plenum reaches a specific temperature the limit switch sends a signal to the air handler to begin running and delivering warm air to your home.
Original limit switch had a product crosss referenced the number and the mfg spec were 170 open 150 close.
