# York Diamond 80 furnace - 7 red flashes



## user_12345a (Nov 23, 2014)

the net says 7 flashes is loss of flame.

you have to catch it right when the problem occurs, noting sequence of operation, checking for 24v ac at the gas valve when igniter glows. won't see 24v right away, there's a warming up period.



it's worth cleaning the flame sensor with steal wool, easy enough.


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## isaggu (Nov 17, 2017)

I replaced the flame sensor, because I had scrubbed it with steel wool and thought I might have damaged it.

Once the leds are blinking 7 red flashes, I tested the limits using voltmeter. The limits all show 24-27V between each terminal and ground and 0v between terminals. This would mean the limits are fine. This was after the flames are already off.

What seems to be happening is that the furnace runs fine for couple of hours and then something turns off the gas (burners). It tries to start again few times, but goes in a lockout for a longer period. And the 7 red flashes.

During that lockout the symptoms I am seeing are 
the inducer is running
the igniter glows and the flame doesn't start.

So something is preventing it from starting the flame.
I thought flame sensor has to be the problem, but it works fine after the lockout period.

I have tested the limits with voltmeter. I have tested the gas volve, pressure limit.

Any suggestions would be greatly appreciated.
Indy


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## yuri (Nov 29, 2008)

When the igniter glows check for 24 volts at the gas valve. If it is there then the gas valve may be sticking closed. Try tap it gently with a rubber or plastic hammer.

You may also need to check if the valve is getting gas pressure or enough pressure. If you have a gas water heater or other appliance turn it up and see if it works. Your gas meter or regulator may be failing.


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## user_12345a (Nov 23, 2014)

This problem is never caused by open limits.


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## isaggu (Nov 17, 2017)

I mentioned earlier that I had changed the flame sensor. After that I saw the problem occur only once. That's when I posted on this chatroom.

But for now the furnace is running without a problem for last 2 days.

Touch wood. If the problem happens again, I will ask for your advice.

Really appreciate all your suggestions.
Thanks


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## yuri (Nov 29, 2008)

On that furnace ( my Sister had one ) you need to clean the metal in front of the sensor.

It uses DC flame rectification (Google it) and electricity jumps from the sensor ( electrode actually) thru the flame and gets converted to DC. Then it goes thru the metal of the heat exchanger in front of it and back to the board by grounding. The shortest distance it can jump is to the heat exchanger metal in front of the sensor , NOT to the burner.

It looks like galvanized metal and you sand it with some emory paper or clean steel wool to get rid of any corrosion.

It is the area in the red circle in this pic.


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