🧵 Boiler troubleshooting

Anonymous at Tue, 9 Apr 2024 12:18:17 UTC No. 16120755

I have a Weil-McLain boiler that cuts off in alarm after about 5 minutes of running. The boiler was just serviced 3 weeks ago. Pump pressures are good, electrodes were just changed, flue gas analyzer readings are within range, and I cleaned the flame scanner even though it wasn’t dirty. I took a multimeter to the control and it’s within range (5.3-5.5v) then around the 5 minute mark it drops too low and cuts it out. The fuel to air ratio is solid and the transition from low to high fire is like butter. The flame is very consistent before the boiler trips off so I don’t think it could be the flame scanner, it’s very rare they fail. Anyone got any ideas?