RHEEM FlameSensor its not !

[Cosmicmuffin]

RGRJ10EZAJS ser GE5D307F480514597 Got a lo-o-o-ong distance service call.,trying to be smart on what to bring. Unit fires up Ind. motor..,HSI lites burners..,runs for few seconds and shuts down. Flame sensor was cleaned. Then replaced with O.M.E. sensor.,same thing. Customer does mention "flame lite" on board does not come on. Sorry guys thats all Ive got. Thanks ahead!

[danielworkerbee]

Flame sensor must be good.
Clean burners and add grounding wire up to burners.
Check the voltage on the flame sensor wire to ground, should be above 30 volts minimum and hopefully higher.
Could be poor graounding all the way to the elec. panel.
luck dan

[Core_d]

Also flame must be grounded. Make sure flame is not "lifting" off the burner.

[billg]

I would bring a pressure switch, contact cleaner and a board if you have it (i carry these anyway) check flame sensor wire, sometimes the harness gets damp or wet and will lock it out, pressure switch and hoses and check drain trap and hoses.

[Rob_in_WV]

I would bring a pressure switch, contact cleaner and a board if you have it (i carry these anyway) check flame sensor wire, sometimes the harness gets damp or wet and will lock it out, pressure switch and hoses and check drain trap and hoses.

Had this happen to me on a York once. I missed it, fortunately my service manager didn't.

[DOGBOY]

rheem/ruud hsi boards are I found bad about not sending out the proper voltage so the flame sensor is sensing nothing. check micro amps and if below .9 replace the board.

dogboy

[SBKold]

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[Jesjen829]

Flame sensor must be good.
Clean burners and add grounding wire up to burners.
Check the voltage on the flame sensor wire to ground, should be above 30 volts minimum and hopefully higher.
Could be poor graounding all the way to the elec. panel.
luck dan

Do you check this with sensor still connected to wire or remove it and check before it goes off. What do you use to ground the burner?

[DOGBOY]

I check it like I do all others, in series. I disconnect the wire from the sensor then connect one lead of my meter to the sensor and the other lead to the wire, I start the furnace and monitor the microamps. They usually go up after the igniter denergizes.

dogboy

[Jesjen829]

I check it like I do all others, in series. I disconnect the wire from the sensor then connect one lead of my meter to the sensor and the other lead to the wire, I start the furnace and monitor the microamps. They usually go up after the igniter denergizes.

dogboy

If you check it in series how would you check to ground?

[Core_d]

If you check it in series how would you check to ground?

I had the same question on this forum. It was explained to me to check from common to ground on the burner the voltage potiental should be very low around .3 . I experimented with this at my school on a unit with a functioning unit with a flame sensor and got a .45 reading some were around their should prove ground. If its not good on the burner work backwards

[Cosmicmuffin]

Looks like I will be making another trip! Checked continuity from board to flame sensor.,good. Tried all other tests mentioned,could not get my meter to read properly? Did get a low voltage once,around 27? There is two L.E.D. lites on board. Green which works..,and amber (flame) that doesnt,even when burners lite for 5 seconds. Customer says amber lite use to glow. Ordering a board Monday! Has anyone ever tried to "dead" ground flame sensor wire,or hold sensor probe on known good ground! I did, neither worked.

[Mr Bill]

There is two L.E.D. lites on board. Green which works..,and amber (flame) that doesnt,even when burners lite for 5 seconds. Customer says amber lite use to glow. Ordering a board Monday! Has anyone ever tried to "dead" ground flame sensor wire,or hold sensor probe on known good ground! I did, neither worked.

If the flame sensor is not grounded good, the amber light will not come on "ever" also if this unit in an early model 1993-1994 you may just need to install the remote sensor kit. Your new ground will run straight to the board, to the molex plug, the directions that come with the kit are simple and to the point. My guess is since you already have the flame sensor it's been updated, but if the ground is not making a good connection at the molex plug on the board, it will not work, even with a new board, it has to make a good connection at the plug. Until you see the amber light, when its senses flame the thing will always shut down. It could be the board, but everyone I have ever worked on I just had to relocate the ground to the molex plug with the new sensor kit, and it fixed it. If everything else works on it, and it goes through the proper sequence, my bet is it's not the board, you have a ground issue.