TROUBLESHOOTING
27
TROUBLESHOOTING
Note: Before troubleshooting the system, make sure the gas shutoff valve is ON.
The two most common causes of a malfunctioning gas appliance are:
1.Loose wiring connections
2.Construction debris clogging the pilot and/or gas control valve filter
WARNING: Turn off heater and let cool before servicing. Only a qualified service person should service and repair heater.
CAUTION: Never use a wire, needle or similar object to clean pilot. This can damage pilot unit.
OBSERVED PROBLEM | POSSIBLE CAUSE | REMEDY | ||
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Ignitor will not spark or pilot will not light | 1. | No gas supply or shutoff valve is OFF | 1. | Check to see if you have gas supply and |
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| that equipment shutoff valve is opened |
| 2. | Air in gas line | 2. | Repeat lighting procedure several times |
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| to purge all air out of lines. If after re- |
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| peated attempts appliance does not light, |
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| call for qualified service and repair. |
| 3. | Construction debris clogging pilot orifice | 3. | Remove debris and dirt, inspect and |
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| clean any other possible obstructions |
| 4. | Low gas pressure | 4. | Contact your gas supplier to check |
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| pressure |
| 5. | Kinked pilot line | 5. | Have a qualified technician replace pilot |
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| line |
| 6. | Control valve is not opening | 6. | Replace control valve (refer to Replace- |
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| ment Parts, page 29) |
| 7. | No power to unit or the ignition module | 7. | Check that main power is on and that all |
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| or power transformer is bad |
| wire connections are made correctly to |
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| the ignition model (see Wiring Diagram, |
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| page 23). Check for 24 VAC at the |
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| secondary side of the transformer. If 24 |
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| VAC is present and the module does not |
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| operate, have the module replaced oth- |
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| erwise have the transformer replaced |
| 8. | Vent damper not fully open | 8. | Open vent damper until fully locked in |
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| OPEN position |
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Pilot will not stay lit | 1. | Loose wiring on ignitor wire to ignition | 1. | Check wiring connection. Refer to wir- |
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| module and/or poor ground to ignition |
| ing diagram (see Wiring Diagram, page |
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| module |
| 23) and/or check ground wire to ignition |
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| module |
| 2. | Pilot flame too low to sense | 2. | Clean and adjust pilot burner and check |
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| gas supply and inlet pressure to unit |
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| Note: Have a qualified technician replace | |
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| pilot assembly if broken or corroded | |
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No gas to burner, although wall switch is | 1. | Wall switch wires defective or too | 1. | Check electrical connections |
set to the ON position |
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Frequent pilot outage | 1. | Pilot flame may be too low, causing | 1. | Clean and adjust pilot flame for maximum |
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| safety pilot to “drop out” |
| flame impingement on thermopile |
| 2. | Improper venting or excessive blockage | 2. | Have the vent system inspected, includ- |
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| ing the termination cap. Remove any |
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| restriction or obstruction |
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