How do I get the heating function on my Duro therm brisk air unit to work model 570 915 from 89 allegro

SOURCE: will not shut off

Sounds like a stuck relay on the unit itself. Maybe there is a short in the control wire that comes from the thermostat that activates the fan.

The thermostat probably has one hot wire at all times. The thermostat then chooses which wire to send the voltage down based on your selection. One of those wires is probably for the fan only. Make sure that it is in good condition (no bare, pinched or wires)

SOURCE: Dou Therm Brisk Air not running

Turn the ac off go up top the coach and remove the cover. Look for fan blockage, Wasp, mud dauber etc. Caution if it is wasps they will chase you off the end of your coach. Take some spray with you. If there is no blockage the fan motor is toast.
Thanks for using Fixya
Jerry

SOURCE: i have a duo therm brisk air model 57915-001 leak

Could be the drain path is clogged.. Take the cover off & see if you can get it cleaned..

woobie dog

• 1273 Answers
• Posted on Aug 11, 2009

SOURCE: Duo Therm Brisk Air not working properly

The short answer is that some are, and some are not. You can tell by opening the unit and checking the refrigerant lines for ports to add freon. There will be one on the smaller diameter high pressure side and one on the larger diameter low pressure side. Both will be covered with screw on caps covering schrader (bicycle tube) valves if your model is rechargable. If is a refrigerant loss issue, you'll need to locate and repair the leak before you add refrigerant (R-22). If yours is of the type that can be recharged, for making a repair and adding freon, I'd say that you're looking at around $200-$250 USD.
I cannot recommend anyone around Spokane.
Best Regards, --W/D--

SOURCE: Duo Therm kicking on the compressor, getting cold, but no fan!

Shut the power off to the unit, spin the fan blade to see if it spins freely. If it doesn't spin freely, (there appears to be a little drag when you spin it),the bearings are bad, if it does spin freely, then try moving the motor shaft from side to side if there’s any play in the shaft side to side then the bearings are worn and motor needs replaced. Then, check the capacitor, if it’s bulging even slightly, the capacitor is bad and needs replaced. Most of the time people replace the capacitor if motor seems ok. If capacitor is ok, turn power on to see if the motor is getting the proper voltage, if it is and not trying to run, then the windings are probably open, the motor's bad and needs replaced.

Testimonial: "Thank You. Since posting this question yesterday, i removed the cover, the shaft moved quite easily. I spun it and then turned on theunit. It works!"