RV Repair: roof to colemen, restroom trailers, rick coleman

Question
QUESTION: We have many high end restroom trailers.On the roof is the Colemen Mach. We get no heat out of it.We checked the wiring diagram on the unit to see that all wires were plugged into there proper places.I see the lights so slightly dim when I turn form cool to heat but yet the heat does not come out. Many Thanks  Rick @ Maryland Restroom Trailers.

ANSWER: Hi Rick, Coleman Mach is an AC unit. Unless it is equipped with a heat pump. If that is the case then it may have something to do with the temp too low for heat pump to come on. If a heat pump is asked to heat a room that is say 20* and the thermostat is set to 73* then it won't come on. If the room temp is 64* and you set the Tstat to say 73*. then it should come on. If the temp in the room is less than 10* difference than the Tstat set point. A built in lockout engages and the Heat pump won't come on. It will turn on the furnace instead because the furnace has more B.T.Us. Good Luck

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QUESTION: This unit is a self contained roof top mount.It has air and a heat strip in it.They never put off that much heat.Someone told me that they call it a chill chaser.The controls are attached to the bottom of the unit.This is probably similar to what would be in a pop up.Anyhow the heat strip is not working.

Answer
Has it been replaced lately? Or is this a new unit that you just bought and were cking it out? I guess what I'm getting at is, did the unit work in the past and now all of a sudden It won't work. Or did you just buy it and found out it did not work. They replace pretty easily if that is the problem. If the lights are dimming when you turn it on. Then it sounds to me, it getting power and the heat strip is blow.