Does inlet gas pressure
drop more than 2" W.C.
during burner ignition?
Adjust gas
supply regulator
Inadequately
sized regulator.
Y
N
N
Y
N
Y
N
Verify Minimum Gas Supply Piping Requirements of:
Minimum ¾" NPT. (Schedule 40 black Iron Pipe
recommended).
Reconfigure gas
supply piping
Y
Observe burner operation throughthe sight glass located on the combustion insert mounting flange. Normal burner

operation should ignite smoothly, without evidence of coughingor huffing upon ignition. The burner flame should be a blue

flame near the burner surface in a uniform flame pattern. Occasional yellow or white streaks are normal.

Inlet gas
pressure tap
Venturi
adjustment
Does main burner
Light?
Remove high voltage wire connected at the
spark rod and hold approximately ¼" from metal
ground with insulated pliers during the ignition
cycle (3 second spark trial period).
Is there spark to ground?
Y
NCheck spark gap to burner
(see “Spark Rod Gap
Inspection”)
Check resistance of high voltage
cable. Resistance should be 0-1 ohms.
If resistance is high, replace spark
cable. If spark cable is good, replace
Control Board.
N
Y
Can Sparking be seen/
heard at the spark rod
to the burner?
Proceed to next page
With manometer, check inlet
gas pressure. Is it stable
between 7" & 14" W.C. static?
(heater not running)
(see illustrations at right)
Is gas supply pressure
regulator adjustable to
maintain proper and
stable setting?
Y
N
WARNING
120 volt potential
exposure. Use caution
making voltage checksto
avoid personalinjury.
WARNING
Removing screw from
inlet gas pressure tap will
immediately allow gas to
flow from pressure tap.
Note: On higher input models using metal fiber mesh burner a redglow from the burner surface is normal.
45
Check continuity of
spark rod. Is
reading 0-1 Ohm?
YN
Replace Spark Rod
(see “Spark Rod
Gap Inspection and
Replacement”

CHECK SPARK ROD

RESISTANCE

Meter probe

Meter probe

Spark Rod

Volt meter set to

OHM setting

Spark Rod

Voltmeter set to

OHM setting

Serial Numbers including and AFTER GB13006174 and ALL EFR models
45