[EddieDi]

Hi all, I'm trying to resolve an issue with my heater and would rather not call someone out of their home during this pandemic situation. It's not an emergency and so i'd rather try to fix it myself.

The issue as I see it. The air blower comes on, but the inducer fan never turns on. There is a one flash error code. York diamond 80 furnace. There is never any glow to the ignitor, and no flames from the heater.

Things i've done...
1. replaced ignitor
2. cleaned, then replaced flame sensor
3. replaced batteries in thermostat.
4. cleaned the hose that goes from the pressure switch to the inducer motor. It wasn't dirty.
5. replaced pressure switch
6. Tried to "reset" rollover switches. I think i counted 4 in total. I can't really tell if i'm actually resetting them or not.
7. I tested for continuity of the ignitor - i do get a ohms measre and continuity beep from my multimeter.
8. I do not believe there's any voltage to the inducer motor. So i don't belive the motor is bad, but i've ordered one soon to arrive.

any thoughts or suggestions would be greatly appreciated.

 

[roughneck]

Please do not replace random parts. Your costing yourself money for no reason.
Is the unit calling to run?

 

[EddieDi]

I'm not sure what that means but if I shut the power switch off, and then on after a while, it does start with a green LED, and the fan motor kicks in. I hear one click just before the fan motor starts.

The error Diagnostic indicator for 1 flash is lockout caused by flame sensed.

 

[roughneck]

Ok, so it’s calling.
What’s the model number of this furnace? What is the description of that error?

 

[EddieDi]

i tried jumpering R to W on the controller card and i see no difference.

 

[EddieDi]

P4HUA12N06401B York Diamond 80
The error Diagnostic indicator for 1 flash is lockout caused by flame sensed.is all that my cover says.

 

[yuri]

Flame sensed B4 ignition means your flame sensor is grounded/touching metal or the wire to it is shorting to ground and may be bare.

The board thinks you have a flame w/o heat being called for and thinks your gas valve is stuck open and you have a fire.

However if you tested continuity in your igniter it should read about 35-75 ohms and not O.

If you broke the igniter and a piece of it is hitting the flame sensor and causing a circuit to ground maybe that is what the board is sensing.

Steps to check.

#1 take the wires off the igniter at the board and check the resistance and report back here.

#2 make sure the flames sensor is not touching the front of the burner or any metal.

#3 check the wire to it for bare spots and make sure it is not grounded.

You may also have a defective circuit board giving you a false error code but that is pretty rare.

Post a pic of the furnace with the doors off.

Pretty sure it is the same one my Sister had in her old house and I have seen hordes of them.

 

[EddieDi]

ok. In the lower right hand corner, there is a 4 cable white connector. The top two give me 7.26 and the bottom two give me 0.1 when i set me multimeter to ohms.

FYI.. the furnace is on when i did my testing.

 

[yuri]

To test the igniter you have to unplug the white molex connector in the bottom pic with the 2 wires going to the igniter and do it with the power off.

I don't think that is your problem.

It seems like the flame sensor is shorting to ground for some reason.

The board looks like a Honeywell Universal replacement rather than a OEM York but that should not matter.

The flame sensor is actually a live electric probe with AC volts on it which jump thru the burner flame and rectify to DC when there is a flame. Then it goes back to the board thru grounding.

If the board reads a AC voltage or signal B4 startup it locks out and gives you that code.

 

[roughneck]

Check mA of the flame rod.
If it’s 0 and your getting the error it could be a board problem.
You may as well cancel the inducer you ordered. It’s not the fix for your problem and is likely just money wasted on unnecessary parts.

 

[sktn77a]

As a rule, the first thing to come on is the inducer motor. If the pressure switch senses adequate airflow, the gas valve then opens and then the blower motor comes on. You say the blower motor is coming on without the inducer motor running? Something is amiss.

 

[surferdude2]

Does it start the inducer if you keep the flame sensor unplugged? That should allow the inducer to start if the flame sensor is bad. The rest of the start sequence would also work until the burner lights and the board shuts it down with a "flame not detected code."

Is the inducer motor free to spin by hand? Does it get warm? You should have measured voltage to it before ordering a new one.

I think your board is bad.

 

[Missouri Bound]

As a rule, the first thing to come on is the inducer motor. If the pressure switch senses adequate airflow, the gas valve then opens and then the blower motor comes on. You say the blower motor is coming on without the inducer motor running? Something is amiss.

Sounds like something is wired incorrectly.

Eddie.....have you made sure the wires are where they are supposed to be?

 

[Missouri Bound]

You won't get a flame until the draft inducer is working. The blower is timed.
How is the inducer motor wired? Does it have a centrifugal switch?
How is the draft proven?

 

[beenthere]

Disconnect flame sensor from the board/controller. If you still get the flame sensed error, the board needs replaced.