I have a confortmaker furnace and the blower motor fails to work in the A/C or heating mode. The motor and capacitor check out as good. What is the mostly likely problem?

Next thing up the chain to check is the control board. Are you getting voltage on the control board where the motor plugs in?

Try shuting power off to your hvac unit.once the power is off dissconnect your thermostat you should have a red wire which is power, green wirewhich is fan motor,yellow wire which is cooling,and a white wire which is heat if you put your green wire and red wire togther and turn your power on you should get a fan. If not take wires apart and check for voltage you should have 24 volts between red wire and green or red or yellow

If your fan starts with red and green wire together while disconnected from t-stat your t-stat is bad .

Quote:

---

Originally Posted by jron

I have a confortmaker furnace and the blower motor fails to work in the A/C or heating mode. The motor and capacitor check out as good. What is the mostly likely problem?

---

What tests did you do that tells you the motor and capacitor are good? Did you actually put 120v straight to motor wires and it ran fine? Let me know a little more about your testing, and I will try ot help.

If you set the thermosat fan setting to on, does the blower come on.(does the blower come on ever)