User Guide

All installations and services must be performed by qualified service personnel.
CHECK CONNECTIONS
TO GAS VALVE. IF OK,
REPLACE GAS VALVE.
IS THE VARIABLE
SPEED AIR FAN
OPERATING?
DOES BLOWER
SPIN FREELY?
CONFIRM IF EITHER
BLOWER WHEEL
IS RUBBING AGAINST
HOUSING OR MOTOR
SHAFT IS SPINNING
FREELY AND REPAIR
OR REPLACE AS
NECESSARY
DOES SYSTEM RUN
UNTIL THERMOSTAT
IS SATISFIED?
CHECK ALL WIRING FOR
LOOSE CONNECTIONS.
NO
NO NO
NONO
YES
YES
YES
YES
YES
REFERENCE ECM
OPERATION MANUAL
IS THERE 24 VOLTS
ACROSS "MVH" AND
"MV COM" ON
50V51-843 CONTROL?
REPLACE THE
50V51-843 CONTROL.
IS LED LIGHT
ON 50V51-843
CONTROL FLASHING?
REFERENCE LED
CHART ON PG. 48
OF THIS MANUAL.
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