SERVICE PROCEDURE D24-II
Pilot Operation Testing
CAUTION
Be Careful When Making Voltage
Measurements or Jumping Terminals
Not to Damage orDeform Connectors or
Connector Pins.
DANGER
120 volt exposure. To avoid personal injury,
use caution while performing this procedure.
Condition:
Pilot lights, no or low fla me signal. Control
Display shows “4” or “62” for Error Cod es
(Service Needed). Cont rol continues to spa rk
untilsystem “Lock Out”.
Main burner willnot light.
The microamp output of th e pilot may be
checked by entering “Se rvice Mode” on the
water heater display and p ressing “Select”
until the flame current is shown. The control
must bein the heating modewith the pilot lit
to display a reading. See section on
accessing service mode on the water heater
display.
Micro-amp readings
0.000 Micro Amp = Replace controlboard or pilot if wireis
damaged.
1.0 micro amp or less= Clean pilot flame rodorreplace pilot.
Checkf or loose or damaged ground wire (s)
from gas valve to contro l board. Check
continuity ofwireswith ohmeter. Are ground
wires okay?
Check for loose or damaged flame sense
lead from pilot to Control B oard. (see
illustration to the right). Is fla me sense lead
okay?
Repair wire lead
or replace pilot.
Repair ground
wire(s) or replace
as needed.
NOTE:
Check continuity of sense lead
toflame rod. If no continuity,
clean pilotflame rod orreplace
pilot. Check pilotflame
appearance - if weak check for
clogged pilot orifice, bent pilot
tubing, or low inlet gas
pressure.
(see above illustration)
Y
Y
N
N
Check venting conditions or nega tive
pressure.
Is vent system okay?
Correct improper
venting condition.
Refer to Installation
Instructions
N
Is heater condensing causing pilot
interruption?
Make sure pilot shield is in place
andnot bent or damaged(refer
to section on main burner and
pilot assembly) . Determine
cause for condensing and
correct.
(Possible under sized water
heater or high demand periods.)
Y
Y
N
Pilot flame sensor microampoutput
shown in display using service mo de.
Pilot mustbe lit to get reading.
Multi-meter set
to check
continuity.

Flame rod

Meter

Probe

Meter

Probe

Checking pilot flame sens or wire and flame

rod for continuity.

Page 29

Heating Flame Current
ȝA
SELECT SE
T
StatusOperational
29