Hayward H400FDN - IF Code

“IF” Code
Turn on main
gas supply &
retest
YES
NO
Inspect gas
valve in heater
NO
Is heater’s gas
valve ON?
YES
Is main gas
supply ON?
Are
connections
secure?
Turn ON gas
valve and retest
YES
NO
52
12. Service LED ON: “IF” Code
On ICB, verify flame
sensor & gas valve
connections are
secure
Secure
connections
& retest
YES
YES
NO
Is inlet
pressure
correct?
Adjust
manifold gas
pressure
YES
Correct inlet
gas pressure
NO
Test 22-28VAC to
gas valve during
call for heat
(manometer
attached)
Is voltage
correct?
NO
Replace ICB:
FDXLICB1930
YES
Is there
manifold gas
pressure?
Replace gas
valve:
Please refer to
(pg. 20)
NO
YES
Is inlet and
manifold gas
pressure correct?
Go to
section B
(next page)