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HSI fireplace: ignitor glows but no flame
What is going on
The hot surface ignitor heats up but the burner does not light.
Likely causes
- No 24 VAC reaching the module or gas control
- Open high-temperature limit or glass microswitch not pressed
- Gas control (valve) not opening
- Wiring fault
Check in this order
- With the rocker ON 110/120 VAC at transformer terminals 1 and 3 (if not, check REM, breaker and wiring), and 24 VAC at terminals 4 and 5 (if not, replace the transformer).
- Check 24 VAC between 24 V and 24 V GND on the module. If missing, test the high-temperature limit (normally closed, must have continuity) and make sure the glass microswitch is pressed in.
- Check every wire connection, then check for 24 VAC at the gas control. With 24 VAC present and no gas flow, the gas control is the next suspect; confirm gas supply and pressure before replacing it.
Applies to: Heat-N-Glo HSI fireplaces
More gas fireplace guides
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- HSI fireplace: flame comes on but will not stay lit
- HSI fireplace: hot surface ignitor will not glow
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Source: Heat-N-Glo DSI / HSI Troubleshooting Guide (Professional Development), Section 7 HSI, p.53. Written in our own words; check the manual for your exact model.
For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.