Stardance Direct Vent/Natural Vent Gas Heater
Troubleshooting / Honeywell #8420 Gas Control System
NOTE: Before troubleshooting the gas control system, be sure the external gas shutoff is in the “ON” position.
WARNING: REMOVE THE GLASS PANEL BEFORE PERFORMING ANY GAS CONTROL SERVICE WORK.
| SYMPTOM | POSSIBLE CAUSES | CORRECTIVE ACTION |
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1. | Spark ignitor will not | A. Defective or misaligned elec- | Using a match, light pilot. If pilot lights, turn off pilot |
| light | trode at the pilot | and push the ignitor button again. If pilot will not light, |
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| check gap at electrode and pilot - it should be 1/8” to |
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| have a strong spark. |
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| B. Defective ignitor (push button) | Push piezo ignitor button. Check for spark at elec- |
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| trode and pilot. If there is no spark at the pilot, and |
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| electrode wire is properly connected, replace ignitor. |
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| A. Defective pilot generator (ther- | Check pilot flame. It must impinge on the thermo- |
2. Pilot will not stay lit | mocouple) | couple or thermopile. NOTE: This pilot burner as- | |
| after carefully fol- |
| sembly uses both a thermocouple and a thermopile. |
| lowing the lighting |
| The thermocouple operates the pilot flame. Tighten |
| instructions |
| the thermocouple. The thermopile operates the main |
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| valve (ON and OFF). Clean and/or adjust pilot for |
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| maximum flame impingement on thermocouple and |
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| thermopile. |
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| B. Defective automatic valve op- | Turn valve knob to ‘Pilot’. Maintain flow to pilot; mil- |
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| erator | livolt meter should read greater than 10mV. If the |
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| reading is okay and the pilot does not stay on, re- |
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| place the gas valve. NOTE: An interrupter block (not |
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| supplied) must be used to conduct this test. |
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3. | Pilot lights, no gas to | A. Remote switch or wires defec- | Check rocker switch and wires for proper connection. |
| burner, valve knob | tive | Use jumper wires across terminals at rocker switch. |
| ON, remote switch |
| If burner lights, replace rocker switch. If okay, use |
| (rocker switch) ON |
| jumper wires across rocker switch wires at the valve; |
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| if burner lights, wires are faulty or connections are |
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| bad. |
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| B. Thermopile may not generate | 1. Be sure wire connections from thermopile at gas |
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| sufficient voltage | valve terminals are tight and thermopile is fully |
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| inserted into pilot bracket. |
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| 2. One of the rocker switch wires may be grounded. |
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| Remove rocker switch wires from valve terminals. |
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| If burner now stays lit, trace rocker switch wiring |
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| from ground. It may be grounded to the appliance |
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| or the gas supply line. |
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| 3. Check the thermopile with a millivolt meter. Take |
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| reading at thermopile (“TP” and “TP/TH”) terminals |
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| of gas valve. Should read 325 millivolts minimum |
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| while holding valve knob depressed in PILOT po- |
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| sition and with rocker switch OFF. Replace faulty |
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| thermopile if reading is below specified minimum. |
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| C. Plugged burner orifice | Check burner orifices for debris, and remove. |
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| D. Defective automatic valve op- | Turn knob to ON, place rocker switch to ON, millivolt |
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| erator | meter should read greater than 10 mV. If the read- |
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| ing is okay and the burner does not light, replace the |
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| valve. |
4. Frequent pilot out- | A. Pilot flame may be too low or | Clean and/or adjust pilot flame for maximum flame | |
| age | high, (blowing or lifting), caus- | impingement on thermocouple and thermopile. |
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| ing the pilot to drop out |
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| B. Possible blockage of the vent | Check the vent terminal for blockage. |
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| terminal |
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