Arrived on site to figure out why boiler was making a popping noise and shooting out soot on startup. Upon arrival, we found that the boiler was actually rolling out on startup. We pulled the burners and pilot assembly. We removed the vent to clean the top of the heat exchanger. After cleaning it we tried ignition again. Same outcome, boiler flames rolled out the front. We found that the regulators outside were very old and past their lifespan. We adjusted the gas pressure to as close to 10” w.c. As possible. We believe the old regulators could be the cause of the flame rollout. As of right now, as long as the pilot does not go out, the flame rollout should not happen. We cycled the boiler 4-5 times using the thermostat and no rollout had occurred. We determined it was safe to run for now but the propane company should come out and replace both outdoor regulators.
