atwood water heater issue

[waninae39]

two failed circuit board so far aarrggh!

I've replaced it with a dinosaur UIB64 board

now i'm getting flames out the slot between the gas value and the end of the tube where the flame is.

PLUS, i have always being seeing soot out of the exhaust

the Atwood manual suggested spiders in the tube. i will clean that to remove the yellow flames that randomly appear. i hope that fixes it

BUT how do i adjust the air fuel mixture to remove soot

more air?
less air?

any suggestions?

[rmkrum]

What you describe is a blockage somewhere between the air shutter (slotted thingie) and the exhaust. It’s basically backfiring because the flame is blocked.

First make absolutely sure the entire flame path from the slotted area out the exhaust is free of wasp and mud dauber nest material. Run a bottle brush through the entire flue, then use compressed air to blow out the junk blowing at the air shutter end only. Wear eye and face protection. There may be flying bits of stuff, dead bugs, etc. Coming your way at high velocity.

If you have to disassemble parts to clean fully, take pictures first. Don’t ask how I know this...

Clean and reassemble. Then the ‘shutter’ gets adjusted, with the flame on, until it is a steady, relatively quiet blue flame. Yellow indicates too much gas, not enough air. Make sure the water heater has water in it for this step!!!!

A tiny adjustment to the shutter makes a big difference. Be gentle and gradual. Tighten the screw gently. It can easily strip out and screw up everything....and make keeping the adjustment set very difficult.

[waninae39]

thank you

i'll go through those steps