A.O. Smith 120 trough 500 Water Heater User Manual


 
BTR TANK TYPE HEATERS
SERVICE HANDBOOK
A.O. Smith Water Products Service Handbook
Irving, Texas ©2000 Training Department
31
TROUBLESHOOTING THE EFFIKAL STYLE DAMPER (continued)
Condition:
Thermostat closed, damper is open fully
STEP A3 TEST FOR 24VAC BETWEEN BLACK AND YELLOW
IF THEN
24VAC is present This is correct – continue to Step 11
24VAC is not present
SeeStep9
Check the harness plug connecting ----
Check that cam on shaft rotates with
shaft
Replace the damper board