RHEEM FlameSensor its not !

[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.

[Cosmicmuffin]

Some good points Mr.Bill..This is 1995,sensor wire does run to molex plug at board,has one harness plug inline,,i checked both. I did run a jumper wire from burner/sensor ground to board ground.

[JBM1000]

Isolate the flame sensor out of the equation. If you have above 45 volts to, I want 96 volts (Flame Sensor Sending Wire To Meter To Ground). Next just grab an 8 penny nail, hooked to sending wire and hold like a surgeon with needle-nose pliers and keep in flame and see if you get Amber light. If you have seen amber even for just a second then there "WAS" a path. Now its back to basics, Ground or board line output.

[Mr Bill]

Isolate the flame sensor out of the equation. If you have above 45 volts to, I want 96 volts (Flame Sensor Sending Wire To Meter To Ground)..

Are you talking about the HSI or flame sensor? I did not know there was voltage to the flame sensor, I thought the flame sensor just proved itself to ground by micro amps, hey we don't do a lot of heat in Houston, so I could be wrong.

[Core_d]

Are you talking about the HSI or flame sensor? I did not know there was voltage to the flame sensor, I thought the flame sensor just proved itself to ground by micro amps, hey we don't do a lot of heat in Houston, so I could be wrong.

On the trane units at our school they say say should be between 30/50 volts.Units at my apt are much less around 5v. They stay energized the whole time u have a call for heat

[rob air]

The flame might not carry over everytime to the sensor. Clean or widen burner slot slightly.

[Cosmicmuffin]

Got it! But ugly.. Went back with new board and installed. Same thing inducer starts.HSI glows,burners lite,runs for 3 sec. flame goes out. Flame lite on board does not lites! Home owners looking over my shoulder whole time,more questions than a two year old! Figure its got to be wire from board to F.Sensor. make up jumper from Molex plug straight to F.S. grd screw. Nothing! Time to check main power supply in furnace cabinet. Open up, take voltage 115V. Decide to jumper neutral and ground wire "SPLASH" W.T.F.!! Now I start interogating home owner.,He had done some "clean up" work in his Main power box this summer.,he had not been using furnace yet this year cause he was out of Propane.,he never thought that could be the problem,cause A/C worked fine all summer! I made up extension cord to another elec. circuit.,thing worked fine! Home owner says smiling.,well atleast I dont need that exspensive board ! And I said you might as well keep it...,your paying for it! Consider it an "Electricians charge"! Thanks all for the help!

[coolerguy]

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!

2 suggestions, check ground from stepdown transformer compared to print, in other words, some transformers secondary sides one lead must be grounded to the case. Secondly, check make sure the furnace itself is grounded. I learned this lesson the hard way, with the same symptoms.