Cleveland SteamCraft 10 Service Manual page 210

206 SteamCraft 10 Service Manual, Chapter 8
TROUBLESHOOTING ——————————————————————————————————————————————
IMPORTANT
1. The following service procedures are provided as a
general guide. Follow appliance manufacurer's service
instructions if available.
2. On lockout and retry models, meter readings between
gas control and ignition module must be taken within
the trial for ignition period. Once the ignition module
shuts off, lockout models must be reset by setting the
thermostat down for at least one minute before
continuing. On retry models, wait for retry or reset at
the thermostat.
3. If any component does not function properly, make
sure it is correctly installed and wired before
replacing it.
4. The ignition module cannot be repaired. If it mal-
functions, it must be replaced.
5. Only trained, experienced service technicians should
service intermittent pilot systems.
Perform the checkout on page 11 as the first step in
troubleshooting. Then check the appropriate troubleshooting
guide (Fig. 14 or 15) and the schematic diagram (Figs.16-17)
to pinpoint the cause of the problem, see Ignition System
Checks below to isolate and correct the problem.
Following troubleshooting, perform the checkout proce-
dure (page 11) again to be sure system is operating normally.
IGNITION SYSTEM CHECKS
STEP 1: Check ignition cable
Make sure:
Igniton cable does not run in contact with any metal
surfaces.
Ignition cable is no more than 36 in. [0.9 m] long.
Connections to the ignition module and to the igniter or
igniter-sensor are clean and tight.
Ignition cable provides good electrical continuity.
STEP 2: Check ignition system grounding. Nuisance shut-
downs are often cause by a poor or erratic ground.
A common ground, usually supplied by the pilot burner
bracket, is required for the module and the pilot burner/
igniter-sensor.
• Check for good metl-to-metal contact between the pilot
burner bracket and the main burner.
• Check the ground lead from the GND(BURNER)
terminal on the module to the pilot burner. Make sure
connections are clean and tight. If the wire is damaged
or deteriorated, replace it with No. 14-18 gauge,
moisture-resistant, thermoplastic insulated wire with
105° C [221° F] minimum rating.
— Check the ceramic flame rod insulator for cracks or
evidence of exposure to extreme heat, which can
permit leakage to ground. Replace pilot burner/
igniter-sensor and provide shield if necessary.
— 1f flame rod or bracket are bent out of position,
restore to correct position.
STEP 3: Check spark, ignition circuit. You will need a short
jumper wire made from ignition cable or other heavily
insulated wire.
Close the manual gas valve.
Disconnect the ignition cable at the SPARK terminal on
the module.
14
Printed 3/93
Models 24-CGA-10 and 24-CEA-10
WARNING
When performing the following steps, do not touch stripped
end of jumper or SPARK terminal. The ignition circuit
generates over 10,000 volts and electrical shock can result.
Energize the module and immediately touch one end of the
jumper firmly to the GND terminal on the module. Move the free
end of the jumper slowly toward the SPARK terminal until a
spark is established.
Pull the jumper slowly away from the terminal and note the
length of the gap when sparking stops. Check table below.
ARC LENGTH ACTION
No arc or arc less than Check external fuse, if provided.
1/8 in. [3 mm] Verify power at module input
terminal. Replace module if fuse
and power ok.
Arc 1/8 in. [3 mm] or Voltage output is okay.
longer.
STEP 4: Check pilot and main burner lightoff.
Set the thermostat to call for heat.
Watch the pilot burner during the ignition sequence. See
if:
iIgnition spark continues after the pilot is lit.
iThe pilot lights and the spark stops, but main burner does
not ligh t.
i S8600B,H,M; S8610B,H; S8660D; S8670D only: The
pilot lights, the spark stops and main burner lights, but the
system shuts down.
c If so, ensure adequate flame current as follows.
i Turn off furnace at circuit breaker or fuse box.
i Clean the flame rod with emery cloth.
Cleveland Range., Inc.