Lennox Boiler Troubleshooting
Common Lennox boiler problems in plain English — likely causes, the fault codes behind them, the safe checks you can make, and when to call a licensed BC gas technician.
Lennox gas boilers (such as the GWB8-IH) report a named fault condition on the control. This reference explains the common Lennox boiler faults — what each means, the likely causes, and why ignition, flame, blower and venting faults must be diagnosed by a licensed BC gas technician.
Boiler repair is licensed gas work in BC. Use these guides to understand the problem and make the safe checks — but never work on the gas, combustion or safety controls yourself. If you smell gas, leave and call 911 or FortisBC at 1-800-663-9911 from outside.
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Lennox troubleshooting — FAQ
What are the most common Lennox boiler problems?
The most common Lennox boiler problems we see in Greater Vancouver are no heat, ignition and flame-loss lockouts, overheating, venting / air-pressure faults and pressure loss. Lennox boilers show a fault code when a safety circuit trips — we document 6 of them with causes and fixes.
Can I fix my Lennox boiler myself?
Only the basics — checking the thermostat, power, gas isolation valve and system pressure, and reading the fault code. In British Columbia, work on the gas, combustion or safety controls of a Lennox boiler must be done by a licensed gas fitter. Reset at most once; if a fault returns, call GasBoilers.ca at 604-359-1081.
Do you repair Lennox boilers across Greater Vancouver?
Yes. Our Red Seal–certified, TSBC gas-licensed technicians service Lennox GWB8-IH gas-fired hot water boilers across Vancouver, Burnaby, Surrey, Richmond, the Tri-Cities and the rest of Greater Vancouver, with same-day appointments often available.
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Get your Lennox boiler diagnosed by a licensed technician
Red Seal–certified gas technicians across Greater Vancouver. Upfront pricing, same-day service available.