34 | TROUBLESHOOTING |
Electronic Ignition System |
TROUBLESHOOTING
Electronic Ignition System
Note: For additional help, visit DESA’s technical service web site at
www. desatech.com
Note: All troubleshooting items are listed in order of operation.
WARNING: Turn off heater and |
| CAUTION Never use a wire, |
let cool before servicing.Only a quali- |
| needle, or similar object to |
fied service person should service |
| clean pilot. This can damage |
and repair heater. |
| pilot unit. |
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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
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, and 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 pi- |
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| lot line |
| 6. | Control valve is not opening | 6. | Replace control valve (Refer to Replace- |
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| ment Parts, page 36) |
| 7. | No power to unit or the ignition module | 7. | Check that main power is on and that |
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| wire connections are made correctly to |
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| the ignition model (see Wiring Diagram, |
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| page 19). Check for 24 VAC at the sec- |
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| ondary 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. |
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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 |
| 19) and/or check ground wire to igni- |
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| tion 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 | |
Frequent outage of main burner and pilot | 1. | Pilot flame may be too low to sense flame | 1. | Cleanandadjustpilotflameformaximum |
after complete ignition sequence. |
| causing ignition module to shut down |
| flame across sensor rod. |
| 2. | Improperventing,excessiveblockage,or | 2. | Have vent system inspected, including |
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| high wind conditions. Overdrafting of |
| the termination cap. Remove any restric- |
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| straight (no offset) vertical vent systems |
| tion or obstruction. Add restrictor plate |
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| over 15 feet in height. |
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| over 15 feet (if not previously installed). |
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| www.desatech.com |
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