A.O. Smith 120 trough 500 - Manual (Page 40)

BTR TANK TYPE HEATERS
SERVICE HANDBOOK
A.O. Smith Water Products Service Handbook
Irving, Texas ©2000 Training Department
39
STEP 17 IID MODULE TEST
Pilot is lit - Sparking has stopped.
STEP 17. IID MODULE TEST (Power to the Main Valve). Using a multimeter, test for
24 VAC between terminal MV on the IID and 24V (GND).
IF THEN
24 VAC is not present: • Replace the IID module. Conduct Step
18 before applying power to
replacement module.
24 VAC is present: • Go to step 18.