B2" Code - Hayward HC Series Troubleshooting Manual

16. Service LED ON: "b2" Code
"b2" Code stands for "Gas valve sensed as "ON" error. If gas valve is powered when it should be off, the heater
will shut down and go into lock out. The blower will operate until error condition is corrected.
Power cycle heater
Step 16A
OFF
ON
Power cycle heater, in an attempt to clear the "b2"
code. IF power cycling clears to the "b2" message
and the heater fires, drop the temperature to
suspend heating. IF "b2" reappears, go to step 16B.
55
b 2
Call for heat and test gas valve
Step 16B
With heater in standby mode, test for 24VAC on
the gas valve (black & white wires), IF 24VAC is
present, replace gas valve
replace the ICB
(pg. 25). Otherwise,
(pg. 25).