A.O. Smith HW 300 Installation & Operation Manual page 50

Correct the situation by consulting the
installation or user's manual on how to
adjust pilot flame.
Replace
NO
Is voltage (24 Vac) across terminals
ignition
MV & MV/PV?
module.
Are the wires securely attached to the main
Attach
NO
valve operator on the gas control and to
wires
terminals MV & MV/PV on ignition module?
firmly.
Replace main gas valve.
Replace pilot burner
and/or ground wire.
Replace pilot burner.
Clean rod or replace
pilot burner if necessary.
CHECKING HONEYWELL S-8600H OR S8610M
INTERMITTENT IGNITION CONTROLS
PILOT BURNER LIGHTS BUT MAIN BURNER DOES NOT LIGHT
YES
YES
NO
Does the pilot flame cover 3/8" to 1/2"
of ingniter/sensor rod?
NO
Does spark stay on for more than
15 seconds after the pilot is "proven" (lit)?
Ensure the ground wire and ignition cable are
separate from each other (prevents shorting
NO
out).
Are they in good condition (not brittle, burnt or
cracked)?
NO
Is the ceramic insulator surrounding the
igniter/sensor rod in good condition
(not broken or cracked)?
Is the igniter/sensor rod in good
NO
condition (not worn, corroded, sooted
or damaged)?
50
YES
YES
YES
YES
YES
Replace ignition module.