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 willnot lightor stay lit,
Errorco des 62, or 63 sho wn on Water
Heater Display
Is there 22-27voltsAC output across
terminal pins 8 &2 on “Control” plug
ofCo ntrol Board? Carefully insert
meter probe in wire plug t o check pin
terminals. Make sure control is inthe
trial forig nition sequence (see
Sequence of Operation).
(see photo 13)
N
Y
Loosen pilot tubing conne ction at
the gas valve and soap test.
Is there pilot gas flow o ut of the
gas valve? See pilot illustration
forpilot inspection. (Wires must
be connected to gas valve during
this test).
Tighten pilottube connection at
the gas valve. Check incoming
gas pressure to water heater. if
okay, replace gas valve
Check for clogged or kinkedpilot
tube, clogged pilotorifice. Clean
or replace as needed.
(see“Pilot Burner Inspection”)
Is there 22-27 voltsAC input across
wire leads
“MV/PV” & “PV” (yellow & red wires)
atGas Valve?
(see photo 12)
Check wire harness for dam age or
loose connections. Repair or replace
as needed.
Reset control by pressing the lower
right button under “reset” on the
displayfor 3 seconds. Does control
board start ignition seque nce and
start sparking (sparking n oise at pilot
or atbo ard)
Replace control board
12
Check across “MV/PV” & “PV” Wire
leads to gas valve
Y
YY
N
N
Replace control board.
Is therespark at the pilot?
Check for:
Loose or damaged ignition wire
Grounded pilot electrode
Damaged pilot.
Y
N
Checking for 24
volts output to
pilot valve
(yellow and red
wire pin
terminals) on
control board
“control” plug.
N
Turnon power to the waterheater
and verify proper operation
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