A.O. Smith 120 trough 500 - Manual (Page 25)

BTR TANK TYPE HEATERS
SERVICE HANDBOOK
A.O. Smith Water Products Service Handbook
Irving, Texas ©2000 Training Department
24
STEP 7 THERMOSTAT TEST
STEP 7. THERMOSTAT TEST. Set the thermostat to call for heat. Using your
multimeter, test for 24 VAC between right terminal and ground.
IF THEN
The meter does not read 24 VAC and the jumper wire
between the high limit and the thermostat is in place: • Replace the thermostat
The meter reads 24 VAC: • Go to step 8.
Note: If the high limit to thermostat jumper wire was disconnected earlier to simulate a satisfied
thermostat, reconnect the jumper to the terminals.
Note: A yellow wire from this thermostat terminal connects to the damper PC board.