80m Munchkin high limit

Bill Barrett

What do you guys think about this, Munchkin 80,000 LP
second season,radiant, DHW, fan coil.Erie boiler boss for pump zone control,temp valve on radiant,170* F operating temp on primary loop, with three secondary loops. Ok this boiler was a DOA, bad control board from start, then had delayed ignition, need to change gaskets in burner/gas train manifold, then had to buy a 1500.00 analyzer to adjust co ppm. After we got it running I loved it, modulation is great,quiet operation, etc. Unit ran balance of last heating year flawless, and no DHW problems all summer. This fall LP supplier let the gas run out, Unit never started after that, I get there the high limit is tripped, reset it everything is fine. I never did figure out what running out of gas would have to do with the high limit, but everything checked out ok. Been about 45 days and had another high limit fault, Unit modulates at 170*, pumps and relays seem fine, primary pump is controled off of the Munckin, when unit shuts down I don't seem to get any residual heat gain. Any ideas? Thanks.

munchkin-man

munchkin at 170*

needs to have the control board and the two thermisters replaced if the temp never goes over 170*
We had four of the control boards do this. We replaced the components mentioned above and all is fine. On one job we updated to the new 925 controler and all is fine. So try that.
The fact that you ran out of propane dose not seem to have anything to do with the high limit lock out???????????