Heating, Air Conditioning, Fridge, HVAC/Air conditioing


QUESTION: When i turn my heater on i notice that know matter what i set the thermostat at the fan does not come on. i only have a unit out side should the fan go on in off

Your question is a bit confusing, I'm not sure what type of unit you have, gas electric, heat pump?
If you have a Heating & Cooling thermostat, when you set the thermostat at heat and the thermostat calls for heat the fan should come on after the unit warms up for about a half of a minute or so.
If the fan doesn't come on at all  the unit may have a faulty motor, faulty capacitor, faulty blower control/relay, faulty wiring?  I don't understand the part about "should the fan go on in off"?

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QUESTION: i have a single package air conditioner unit (intertherm model P3RA-042K)
When the heater is on the fan doesn't come on at all no matter what i put the thermostat setting on however the fan does come on when i put it on the cool setting, the heat and cooling setting is working just fine

It sounds like the blower relay on the unit?
The blower relay gets it's instructions on how to start, stop, and run from the thermostat setting.
the thermostat when in the cooling mode has the blower start immediately when calling for cooling, the blower relay has the blower start in a delay when calling for heat, when you set the fan switch to on the blower relay has the blower start and run constantly.
I think the problem is in the blower relay or maybe the thermostat?
You need a voltage tester to check for power at the proper point of the relay, thermostat etc.  

Heating, Air Conditioning, Fridge, HVAC

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Jim Barnhart


Fifty + years conditioning the air.


Answer questions about , residential and commercial. Answer questions about sheet metal fabrication. Fifty years plus experience. No answers for oil equipment, No answers for kitchen appliances, No answers for laundry appliances, I don't specialize in one particular area of the HVAC area, I'm more of a General Practitioner, Limited in refrigeration/

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