Cliff Notes Version: Can anyone please walk me through proper terminal connections to wire a circulator pump relay switch and AM10 module for a Buderus GB142-45 (propane conversion)
Encyclopedia Britannica Version: Unit installed 09/2019 and worked perfectly for 10 years. I clean it myself annually, have replaced the ignitor and ionization electrode etc.
Last week, I had a Buderus tech come out to do a 10-year inspection on it. He said, "You don't have a relay switch on the circulator pump and you need one". OK, install one. He installs it....the unit would fire for the first heat cycle and then would not respond to heat calls from any of the three zones. In the attached photo of the relay switch, the zone valves are controlled by the brown wire and were hooked to the TT terminals. The white wire went to the red plug of the AM 10. As before, no dice, boiler would not respond to heat calls. I jumped the WA terminal and the boiler fired right up. Plumber tells me to move the white wires from XX to TT and the boiler now functions properly except that the AM10 does not work. He said that power wiring to the relay switch is illustrated incorrectly in the Buderus manual and they told him, " "The installation manual contains an error which they never acknowledged. The manual says power wires for the relay are pulled off the pump circuit but it should say to take power off L1 and L2 off of the boiler circuit and then use X X on the relay to tell the boiler to fire. L1 and L2 from the relay should be put on L1 and L2 on the boiler." I don't know what that means. I am out $1500.00 and now have a boiler that fires constantly. Can anyone please lend a hand with this? Thanks.
Rich
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