York Furnace problem

[williams767]

I have 2 17 year old York furnaces. One is not working. The igniter is not firing. Sequence of operation: gas control and igniter to light pilot, inducer motor,gas control, then main blower motor.

I have swapped several parts from my working furnace. so far this is what I've done:
Swapped ignition module(Honeywell).
Swapped igniters.
Swapped gas controller.(Honeywell)
Swapped pressure switch.
Checked continuity on 2 overheat switches.
Swapped thermostats.

When I turn unit on a relay clicks but nothing else happens.

Any suggestions would be appreciated.

[paul52446m]

I have 2 17 year old York furnaces. One is not working. The igniter is not firing. Sequence of operation: gas control and igniter to light pilot, inducer motor,gas control, then main blower motor.

I have swapped several parts from my working furnace. so far this is what I've done:
Swapped ignition module(Honeywell).
Swapped igniters.
Swapped gas controller.(Honeywell)
Swapped pressure switch.
Checked continuity on 2 overheat switches.
Swapped thermostats.

When I turn unit on a relay clicks but nothing else happens.

Any suggestions would be appreciated.

Hi Paul here. Check the wire going to the igniter for bare spots and take continuity check. Check the hoses on the pressure switch for small cracks, and make sure they are clear inside. Check to make sure you have a full 24 volts at the module. Are you saying that the igniter is not sparking, or it does spark but no fire? Do you have 24 volts to the pilot valve? You have checked all roll out and limit switches. When you check any switches you do have to have the wires off the switch when you check it. Later Paul

[williams767]

Paul
I'm getting no sparking at all. Good continuity on igniter wire. I will double check condition of rubber tube to pressure switch. I havn't checked for 24V.Will do that now.
Thanks.

[paul52446m]

I have 2 17 year old York furnaces. One is not working. The igniter is not firing. Sequence of operation: gas control and igniter to light pilot, inducer motor,gas control, then main blower motor.

I have swapped several parts from my working furnace. so far this is what I've done:
Swapped ignition module(Honeywell).
Swapped igniters.
Swapped gas controller.(Honeywell)
Swapped pressure switch.
Checked continuity on 2 overheat switches.
Swapped thermostats.

When I turn unit on a relay clicks but nothing else happens.

Any suggestions would be appreciated.

Are you sure you have the Sequence of operation right. I was thinking that
on call for heat, if all safety and limit switches are made that the inducer comes on first which makes the pressure switch and then the spark and pilot
gas. If this is true then when you hear the click you should be getting 110 volts to the inducer. later Paul

[williams767]

The seqeence of operation is posted on the furnace
1.Spark ignites pilot
2.Inducer motor is energized
3.Burners ignite
4.Main blower is energized in 20 to 30 seconds

I'm tring to figure out the 24V. I'm getting 26 volts out of transformer(if thats what its called) of of one wire coming out. Zero volts out of the other.

[paul52446m]

The seqeence of operation is posted on the furnace
1.Spark ignites pilot
2.Inducer motor is energized
3.Burners ignite
4.Maim bloer is energized in 20 to 30 seconds

I'm tring to figure out the 24V. I'm getting 26 volts out of transformer(if thats what its called) of of one wire coming out. Zero volts out of the other.

the post on the transformer that you got no power is the ground. You test from that ground to the hot post to get you 24 volts. use that same ground post to test all 24 volt power. Can you lite the pilot with a liter when it click to turn on pilot gas Have you checked the P post on the gas valve when you hear the click.
You only have about 6 seconds to make this test and it will turn off on safety. later paul

[williams767]

It seems now that I'm not getting any 24v to anything. I can hear the transformer slightly buzzing. Unable to light pilot manually. No 24v to PV terminal. I hate to do it, but it might be time for the service call.

[paul52446m]

It seems now that I'm not getting any 24v to anything. I can hear the transformer slightly buzzing. Unable to light pilot manually. No 24v to PV terminal. I hate to do it, but it might be time for the service call.

If they used color code your red wire going out to the stat should be hot,24 volts, and when the stat is made the white wire should be hot coming back from the stat. this should make the module go to to work, and then you should get your PV and spark. paul

[williams767]

If they used color code your red wire going out to the stat should be hot,24 volts, and when the stat is made the white wire should be hot coming back from the stat. this should make the module go to to work, and then you should get your PV and spark. paul

OK. I had my volt meter on DC, my bad.
I have 24v at red and white stat. I don't have voltage at low voltage terminal block.

[paul52446m]

OK. I had my volt meter on DC, my bad.
I have 24v at red and white stat. I don't have voltage at low voltage terminal block.

Testing 24 volts gets a little tricky. you can't test from red to white, thats not doing any good. Check at you stat and see if the red wire is on R post and the white wire on w post. If so go to your furnace and find that transformer again.
Take your tester and test from one post of transformer to cabinet ground to
see which post is 24volt. The other post on the transformer will be ground.
When testing at the furnace leave one lead of your tester on that ground post
of the transformer at all times, for every test that you make.
Now test from that ground to the red wire going to the stat, you should have 24 volts. Now test from that ground post to the white coming back from the stat, should have 24 volts, If not you have a problem in the stat or wring from stat to furnace. Try jumping the r and w post on you module and see if it fires. paul

[williams767]

Testing 24 volts gets a little tricky. you can't test from red to white, thats not doing any good. Check at you stat and see if the red wire is on R post and the white wire on w post. If so go to your furnace and find that transformer again.
Take your tester and test from one post of transformer to cabinet ground to
see which post is 24volt. The other post on the transformer will be ground.
When testing at the furnace leave one lead of your tester on that ground post
of the transformer at all times, for every test that you make.
Now test from that ground to the red wire going to the stat, you should have 24 volts. Now test from that ground post to the white coming back from the stat, should have 24 volts, If not you have a problem in the stat or wring from stat to furnace. Try jumping the r and w post on you module and see if it fires. paul

Paul
Thanks for your time on this. I did what you suggested. I had 24v from red to ground and white to ground. I tried jumping red to white with no luck.

I just called for a professional (I hope). I'll post when we figure it out.

Thanks again.

[williams767]

It turned out to be the ignition control module. Aparently when I had them both out to swap them, I put the bad one back in the same unit. I know I know, I'm an idiot. Thanks for the guidance.

[paul52446m]

It turned out to be the ignition control module. Aparently when I had them both out to swap them, I put the bad one back in the same unit. I know I know, I'm an idiot. Thanks for the guidance.

I thought it might be something like that or maybe a wire crossed.
Anyway i am glad you got it fixed. Later Paul