Cumberland C225, Руководство по эксплуатации и обслуживанию

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46 PNEG-308 Purafire
12. Troubleshooting Guide
Troubleshooting Heater (Continued)
6. Turn the heater OFF. Reconnect the gray wire to terminal #5 of the brain box. Disconnect the yellow
wire from terminal #8 of the brain box. Connect one (1) lead of the voltmeter to terminal #8 and the
other to ground. Turn the heater ON. About 9 seconds after the air proving switch closes, the
voltmeter should read about 24 VAC. If no voltage is read, replace the brain box.
7. Turn the heater OFF. Reconnect the yellow wire to terminal #8 of the brain box. Connect one (1)
lead of the voltmeter to the pink wire on the gas valve and the other to ground. Turn the heater ON.
About 9 seconds after the air proving switch closes, the voltmeter should read about 24 VAC. If no
voltage is read, check the High-Limit switch.
LED will flash 3 times if High-Limit switch is open.
8. If voltage is present at the gas valve, but it does not open, it may be pressure-locked. To reset,
shut off the gas supply and remove both plugs from the pressure taps from the gas valve. Replace
plugs and slowly turn gas ON. (Turning the gas rapidly causes pressure-lock) If the valve is not
pressure-locked and still does not allow gas to pass, replace the gas valve.
LED will flash 3 times
if gas valve is not working properly.
9. Turn the heater OFF. Connect one (1) lead of an ohmmeter to the blue wire at the flame probe and
the other to ground. The meter should show no continuity. If continuity is shown, check for a short
to ground. If no short is found, replace the brain box.
NOTE: For this step, you must use a digital voltmeter.
10. Turn the heater ON. Connect one (1) lead of a voltmeter to the blue wire at the flame probe and
the other to ground. The voltmeter should read between 35 and 100 VAC. If it does not, remove
the flame probe and clean off any corrosion, replace the flame probe and recheck the voltage. If it
is still not within the specified range, the brain box may need to be replaced.
NOTE: For this step, you can use an analog or digital ammeter.
11. With the heater OFF, connect one (1) lead of the ammeter to the flame probe. Connect the other
to the blue wire. Set the meter to the DC micro-amp (not milli-amp) range. Turn the heater ON. The
ammeter should read at least 1.3 amps. If it does not, remove the bolt that centers the orifice body
in the main cast burner. Use a piece of sandpaper or emery cloth to “shine” the bottom of the burner
and the sheet-metal base that it contacts. Replace the bolt. Ensure that all electrical grounds are
secure. Turn the heater ON. If the ammeter reading does not improve, replace the brain box.
12. If all readings are within the specified range and the heater still does not operate correctly, contact
a qualified service representative.