How to troubleshoot a furnace that will not start.
Winter is just around the corner and people are starting to turn on their heaters/furnace… but no heat!
These steps may seem simple, but I’ve been called out multiple times already to look at 'broken' furnaces that just needed their pilot lights relit. Here is a checklist to run through-
These steps may seem simple, but I’ve been called out multiple times already to look at 'broken' furnaces that just needed their pilot lights relit. Here is a checklist to run through-
- Is the gas to the furnace turned on? The supply pipe handle should be parallel to the gas line.
- Check the pilot light, and follow the unit’s instructions to relight (FYI clean any dust away that may have accumulated over the summer).
- Has the circuit breaker to the gas or electric unit tripped? Reset if necessary.
- Check the thermostat. For electrical thermostats-
- Make sure the heat function is on and the thermostat temperature is set at least 5 degrees higher than the ambient temperature. Works… great! Fails… next…
- Turn off power to the furnace, remove the thermostat cover check the battery, fuse (replace if expired or damaged), and clean off any dust with a small brush or pressurized air. Turn power back on and attempt to turn the furnace on. Works… great! Fails… next…
- With the power off, unscrew the red and white wires from their terminals (or the wires labeled “R” or “Rh” and “W”), and wrap those wires together. Turn power on. If the furnace ignites, then the thermostat is defective (replace thermostat).
- If the furnace does not light, then check that there is continuity (electrical test to determine if an electrical path can be established between two points) from the wires to the furnace. If continuity test fails, call a qualified technician to assist.
Hope this information helps you and your clients. And if you need help lighting pilots or testing a thermostat, I’m available to help :-)
Sincerely,
Kelsey
CA Pro Home Inspection, Home Inspection & Maintenance
To schedule a professional home inspection, or for maintenance issues, please contact me at-
blogger@caprohomeinspection.com
w 805-284-9437
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