M
Mark-519
- gas valve?
- gas pressure too low?
- control board?
- heat sensors?
- overheat thermostat?
- air pressure switch?
- ignition/spark generator?
- flame sensor?
- heat exchanger?
- gas pressure too low?
- control board?
- heat sensors?
- overheat thermostat?
- air pressure switch?
- ignition/spark generator?
- flame sensor?
- heat exchanger?