Microamps

Darin(in Michigan)

Just changed a Johnson Controls G-60 that was locking out. The flame signal would be fine and then spike to 11 and "pop" no flame. As long as it was below ten it would work. Some of these guys are better to talk to though. Good advice from the others.

Unknown

What are the perimeters for Microamps?

Most of the service manuals and instructions list that a range of 2 to 10 microamps is correct with 3 to 5 being the norm. Most know what to do if readings are below 2:

1. Clean pilot

2. Clean Flame Rod

3. Check for good ground

4. etc

What about readings over 10 what is the deal with that? What should you do?

J.C.A._3

My next step...

Would be to re-affirm the ground, then check to see that the pilot flame and main flame are where they belong.

I'm thinking that there might be a crack in the porcelin and the current is being further induced by the leakage. Am I close? Chris

Glen

OK - I'll bite ....

as flame signal is a function of flame rod length and grounding area - I would check flame rod length and flame interference - and adjust if necessary. And yes while we do have parameters - do any controls shut down if the signal is too high??? None that I have found ....

Darin(in Michigan)

Honeywell s 8610U1003

I think thats the number. It was reading a miroamp signal unlike anything I've ever seen(over 26). My Fieldpiece was toning a warning as if to say "TURN IT OFF!!! I put the old control back on and the problem went away(the flame sensor wire was broke at the base of the sensor on a WM boiler)

Unknown

Here is what I am told:

Anytime you get in excess of 10 microamps (unless the system requires higher - some Fenwal system do) then it is electrical interference from some source. It could be a poor connection up to and including electronic feed over from within the printed circuit board. Suggested solution replace the electronics. My personal experience with this is that if left alone it will result in a call-back. I have taken to just changing the boards and have found it works the majority of the time. I did have one job that was getting interference from an outside source but that is unusual.

Unknown

Here is the Microamp

posting for Rob.

rob

Thank-you.