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v8_dave
Jan 19, 2008, 09:07 PM
Hello, I am visiting my uncle and his natural gas furnace is not working for forced air heating. There is hot water in the house, but I cannot get heat. I replaced the thermostat and can't even get the blower to operate in ON, never mind AUTO. He says it has been very temperamental lately where it won't start with the blower in auto and he has had to reset the main breaker and play with the thermostat.

Any tips for diagnosis tomorrow? I plan to try to jumpstart the blower to see if the motor is fine. Thanks guys, I have 24hrs to fix this problem for him. :)

hvac1000
Jan 19, 2008, 09:34 PM
Check for 24 volts a the transformer. Brand and model of unit?

v8_dave
Jan 19, 2008, 10:56 PM
I will check that all in the morning. Thanks for the help!

Also, I noticed the fan does not come on for a/c use either.

v8_dave
Jan 20, 2008, 03:11 PM
OK, I think I diagnosed it pretty sufficiently; the blower motor hums loudly and locks up solid even after spinning it freely. So are you thinking the motor is bad or the capacitor?

It is a 2001 Bryant 383K.

hvac1000
Jan 20, 2008, 04:21 PM
Motor lock up = bad motor. Replace the motor and the correct capacitor at the same time.

v8_dave
Jan 20, 2008, 05:00 PM
Motor lock up = bad motor. Replace the motor and the correct capacitor at the same time.

OK, thank you! It also spits out a code 12. I will have him call a service tech after the holiday.

Moose1123
Jan 20, 2008, 05:10 PM
Hello, I am visiting my uncle and his natural gas furnace is not working for forced air heating. There is hot water in the house, but I cannot get heat. I replaced the thermostat and can't even get the blower to operate in ON, never mind AUTO. He says it has been very temperamental lately where it wont start with the blower in auto and he has had to reset the main breaker and play with the thermostat.

Any tips for diagnosis tomorrow? I plan to try to jumpstart the blower to see if the motor is fine. Thanks guys, I have 24hrs to fix this problem for him. :)
I have a similar problem. I have a York Diamond 80 Furnace. My heater will come on but the blower does not put out the air movement. My blower motor is run off 120VAC and uses a starting Capacitor. I have removed the start capacitor and found it to be bad. You can find the procedures for how to test a capacitor on the internet. I was unable to find a supply store that carried the capacitor I need so I ordered one online. I have not received it yet, so I can not tell you if my motor is faulty as well. Yet, that is a place for you to start.

golfmeister
Feb 4, 2008, 10:00 AM
Furnace motor quit. I turned off electricity to furnace, spun squirrel cage, turned elect. Back on and the blower worked. After a few hours blower went out again, Now spinning squirrel cage does not fix problem. How do I test 1) Blower motor, or 2) Capacitor?
The furnace is 5 years old (3spd with AC)

dhaniyal
Feb 6, 2008, 10:30 AM
Hi
I have same problem. I started noticing lately whenever heater is running motor was running loud(like something is rattling) today we had burnt smell and heater is not blowing any hot air anymore but it looks like everything turns on igniters etc. I put it in a/c mode blower works in that mode. I’m not sure if it is exhausted motor or something else. My unit is York Diamond 80 Model# P4HUC20118001B (heater a/c comined) and about 4 years old. Any help will be greatly appreciated.
I also like to know if someone can help me find a parts catalog or service manual on line.

hkstroud
Feb 6, 2008, 06:30 PM
Golfmiester,dhaniyl you should each start your on thread, you will get more responses.

Golfmiester,
To test capacitor,
Disconnect all wires to capacitor,
With a multimeter, set to resistance, (that the little horseshoe),
Simultaneously touch one lead to each terminal on capacitor.
It doesn't matter which one,
Reverse the leads and touch again.
If the capacitor is good the needle will show a momentary flow of current.

northern62
Nov 15, 2011, 11:23 AM
My new gas furnace doesn't get hot ! The air comes out cold to warm and that's it ! Every time it come on, its cold air to warm and that's it. James