Service Manual

12
PIEZO IGNITER, ELECTRODE TESTING AND REPLACEMENT
With the pilot not in operation (no pilot flame) you can check the Piezo and electrode circuit by viewing pilot
thru the sight glass located on the inner door and observing the spark action.
Step 1. Remove outer jacket door.
Step 2. Repeatedly depress the Piezo igniter while viewing the pilot thru the sight glass. If a spark is
present, the circuit is OK. If there is no spark, proceed to step 3.
Step 3 Remove orange wire from Piezo igniter and install a jumper wire in its place. Hold the other end of
the jumper by the wire insulation or using an insulated tool, next to an unpainted surface such as
the feedline or gas valve and depress the Piezo igniter. If there is a spark, the igniter is OK, the pilot
is not functioning and must be replaced, see SERVICE PROCEDURE RG-III for pilot
replacement. If no spark is present the igniter is not functioning and must be replaced.
Step 4 With orange wire disconnected from piezo igniter. Using a common screw driver, place blade of
screw driver under piezo bracket and gently pry bracket from front of combination thermostat/
gas valve and unhook bracket from rear of combination thermostat/gas valve.
View spark
Action through
Sight glass
Repeatedly
Depress Piezo
Igniter
Common Screw
Driver
SERVICE PROCEDURE RG-IV
Piezo Igniter, Electrode Testing and Replacement