Well, decided it was time to call in an expert. Turned out to be a bad pilot switch.
Appreciate the help. Sometimes it pays to know when you're in over your head.
I'm assuming, which is not always the best thing to do, the the voltage going to the motor should be 115V and not fluctuating between 20.0 and 0.00 volts? Also after unplugging the motor from the circuit board leads, the buzzing/humming noise seems to be coming from a small transformer just...
Thank you for the reply. I'm going to pull the motor tomorrow. We're lucky to have a Graingers less than a couple miles away. That's were our neighbors got theirs from.
Carrier Gas Furnace, Model# 396GAW000075ACAA
This morning awoke to no heat. All was working fine the day previously. Checked thermostat and it appears okay. Checked all the breakers and they are all fine. The circuit board was replaced just 4 years ago. I opened the top part of the furnace...
Thank you for your assistance, Paul. Is there a site I can turn to that will have pictures or diagrams of what I need to do? I'm one of those guys that needs to see it before I do it.
Thanks again.
Gerry
I have been called upon to assist a neighbor lady in fixing a problem she is having with her furnace. It is the same as my own, a 28 y/o Carrier (model #396GAW000075). It starts its cycle without any problems. After it has been running for about 10 minutes or so, the pilot ignitor starts to...
I managed to remove the actual unit's schematic from the cover panal and scanned it. Hopefully this will help as it appears the earlier one was for a different but similar model.
I am trying to get you a link to the manual that has the schematic; however the site from which I got it is currently down.
At the risk of sounding ignorant, in looking at the photos I provided, where would I find that particular switch.
I appreciate the patience.
Gerry
I've included with the schematic a picture of both the upper and lower sections of the furnace. I checked the part number on the black device withe the two red wires attached to it, located behind the gas control unit and it comes back listed as a Carrier Limit Switch (HH12ZA189 replaced by...
Please bear with me as I know little if anything about heaters but am patient when it comes to sorting through a home repair problem, handy with tools and can follow directions.
I have a 25 year old central forced air gas furnace. According to the label inside, it is a Carrier model number...