Furnace runs but does not produce enough heat; the home never reaches the set temperature.
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Possible Causes
How to Fix / Troubleshooting
Safety: Gas input and pressure adjustments must be performed by a licensed technician. Do not adjust gas valve screws yourself.
Homeowner checks:
- Filter and ducts: Ensure the filter is clean and all supply registers are open to allow proper airflow distribution.
- Thermostat settings: Verify the thermostat is not in setback mode or programmed to lower temperatures.
- Check for drafts: Significant air leaks in the home can make the furnace appear undersized.
Professional tasks: A technician should verify the Luxaire furnace input rate, manifold pressure, burner cleanliness, and blower speed tap settings.
Repair Difficulty
Required Part
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