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BillyHvac, Journeyman HVAC Tech
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I have a Carrier WeatherMaker 8000 unit that is not activating

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I have a Carrier WeatherMaker 8000 unit that is not activating the ignitor element. I replaced the ignitor element with a replacement that Grainger Industry said is a compatible replacement. However, the element still does not work. The lite code is 12. Componet diagnostic test(shorting terminal C to Test) is ok except ignitor does not work. Questions: 1)Is replacement part incompatible. 2) Should I replace circuit board and if so what's the part number.
Hello, the 12 code is power applied while thermostat calling. Turn thermostat all the way down, turn fuurnace off and then back on. Then turn thermostat up. Tell me the sequence and code, if any from that point.
Customer: replied 8 years ago.

Not at home to do that.


However, while performing the component test, I removed the termostat wire as instructed from terminal "R" before performing the test. As I indicated, everything worked excepted the ignitor element.


Can do what u requested in about 5 hours when I get home.

Great just let me know back at this question. The 12 code flashes for 90 seconds while the main blower runs if furnace was turned on while the thermostat was turned up. Then after 90 seconds it begins it regular routine. The system of turning the stat down just bypasses that minute and a half. Then record the sequence for me. Good luck
Customer: replied 8 years ago.

Got code 34 - Ignition Proving Failure


I already know there's an ignition problem. I've replaced the ignitor to no avail.


What are the other possible causes and how do I isolate them using voltmeter or other testing technique?


Apparently something is stunting or inhibiting the 115v to the ignitor or possibly the replacement ignitor is incompatible (polarity issue?).


Could the PC board housing the relay be bad? How do I check that and other possible causes?


Your thoughts

Code 34 without the ignitor getting power is a bad board. The ign prove cannot be registered until after an attempt has been made for igniton. But the sensor never has a chance because it never gets power. The problem is a bad control. The deduction comes from all limits closed (which would code open limit) and the pressures switch making (which would code pressure switch) with those items in place and no 120v to ign is bad board.

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Customer: replied 8 years ago.

I'm getting power (120v) off controller board. When I hear relay switch my volt meter reads 120v off the connector plug off. I also see 120v at plug going to ignitor.



recap, 120v to both inducer and ignitor but no inducer and no ignitor?
Customer: replied 8 years ago.

I'm not sure what the inducer is.


I see 120v off the control board plug going to the ignitor element just before the gas is released. However, the ignitor element never glows. The problem seems to be pointing to the ignitor element even though I replaced it.


I ohmed out the element and got a good continuity check w/ a 54 ohms resistance measurement. I also did a continuity check of the wiring to the element which tested good. Could there be a polarity issue w/ the replacement (not original equipment) ignitor I installed? I see that it's keyed to plug in only one way. I was also told that some replacement parts for Carrier equipment does not work. Just throwing that out there.



when you measure the ignitor plug are you touching both meter leads to the plug goin to the ignitor? or one to ground?

Customer: replied 8 years ago.

I plugged both leads of my meter in the connector plug on the controller board with the the connector unplugged and registered 120v.


In other words, the ignitor elememt plug was disconnected from the controller board and both leads plugged into the controller board connector. I read 120v

Customer: replied 8 years ago.



I plugged both leads of my meter in the connector plug on the controller board with the the connector unplugged and registered 0v (low) until the ignition process started and the voltage then read 120v for about 3 to 5 seconds. Then it went back to no (low) voltage reading. The same happened during it second attempt to ignite

Circuit board. Ignition trial has to be at least 30 sec. If you are careful you can find a way to put a steady 120v direct to the ignitor to test. But I still say circuit board
Customer: replied 8 years ago.
I am available for follow up if you have any other questions. Thank you