Start with your symptom
No heat and startup failures
Runs but doesn't heat properly
Noises, smells and safety
The twelve failures behind most service calls
| Component | What homeowners notice |
|---|---|
| Hot surface ignitor | Furnace tries to start, no flame, then silence or lockout |
| Flame sensor | Burners light for seconds, then shut off repeatedly |
| Pressure switch | Inducer runs but ignition never begins — often a blocked vent |
| Blower motor | Furnace heats but no air reaches the registers |
| Run capacitor | Humming at the furnace with no blower rotation |
| High-limit switch | Heat for a few minutes, then shutoff with the fan still running |
| Thermostat | No response to setpoint changes, blank display, or erratic cycling |
| Control board | Unpredictable behavior or no response with good inputs |
| Restricted airflow | Weak airflow, cold rooms, overheating shutdowns |
| Dirty filter | Reduced airflow and repeated limit trips |
| Vent or intake blockage | Pressure switch faults, especially after heavy snow |
| Gas valve | Ignitor glows but no flame appears |
No heat right now? Call 716-412-2677 for 24/7 service availability.
Call now for a free quote and service availability. Please have your 5-digit ZIP code ready.
Checks every homeowner can safely make
- Thermostat set to HEAT with the setpoint above room temperature.
- Fresh thermostat batteries.
- Furnace service switch on and breaker not tripped.
- Blower door fully seated.
- Clean filter of the correct size.
- Outdoor PVC intake and exhaust clear of snow and ice.
- Condensate pump not full and drain not frozen.
- Supply registers open and return grilles unobstructed.
Where homeowner checks end
Do not bypass safety switches, open gas valves, disassemble burners or the heat exchanger, jump control board terminals, or work on live wiring. If these checks do not restore heat, call 716-412-2677.