Hey FDR, he hangs out at alt.hvac. We think he's a hack. This proves it.

"FDR" wrote in message
...

"RP" wrote in message
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Stormin Mormon wrote:
Working on a Rheem natural gas furnace. It's got the "jet" type
burners.
Four burners. 80 percenter.

The inducer blows, the HSI heats, the gas lights. And lights all the
way
across. About a second later, the gas shuts off. And, the whole thing
goes
through the routine again.

The call came in Friday about 6 PM. Didn't have a sensor rod, so Monday
I
bought one.

Now, even with a new sensor rod, and a new grounding screw, it's still
the
same. Fires for a second, and then shuts down.

The furnace is a 1999 model now. Has had essentially no maint except
for
filter changes.

I checked the ground to neutral at the furnace (less than one ohm) and
the
connection between the terminal and the molex connector where it comes
off
the main board. Also less than one ohm. Then checked the ground screw
from
the sensor rod to the 110 VAC ground. Again, nothing.

Guess the only grounding thing I didn't check was that the ground wire
from
the 110 VAC was connected to the case of the furnace. Is that relevant?

What else to check, or is it time to replace the board?

Did you check the flame current? Why did you replace the sensor? Why are
you working on a system that you don't understand?

hvacrmedic

More importantly, whay aren't you asking the "professionals" over at
alt.hvac ? Or as they would tell you there, hire a "professional" LOL.