Low Fire Sequence of Operation: When LCWT rises to 45.5°F, the burner will fire at Low Fire. If the LCWT temperature continues to rise, the burner will stage up to High Fire at 50.9°F. Otherwise, the burner will shut down when the LCWT reaches 41.9°F.

High Fire Sequence of Operation: When the LCWT increases to 50.9°F (adjustable to 47.3°F) the burner goes up to High Fire. It will continue to burn in High Fire until the LCWT reaches 43.7°F at which time the burner will drop back into Low Fire and again follow the Low Fire Sequence of Operation.

Low Fire Sequence of Operation: When LHWT falls to 130.1°F, the burner will fire at Low Fire. If the LHWT temperature continues to fall, the burner will stage up to High Fire at 124.7°F. Otherwise, the burner will shut down when the LHWT reaches 133.7°F.

High Fire Sequence of Operation: When the LHWT falls to 124.7°F (adjustable to 128.3°F), the burner goes up to High Fire. It will continue to burn in High Fire until LHWT reaches 131.9°F at which time the burner will drop back into Low Fire and again follow the Low Fire Sequence of Operation.

• - Standard Design Set Point. This is the temperature that will be held when load exactly equals rated capacity. Cooling Set Point can be adjusted 1.8°F down or 16.2°F up from standard set point. Heating Set Point can be adjusted 12.6°F down or 5.4°F up from standard set point.