Independent guide
Furnace not heating
No heat, or not enough. Start here.
Check these first
- Thermostat is set to Heat and the target is above room temperature.
- Replace the thermostat batteries if it has any.
- Check the air filter.
- Make sure vents and returns are not blocked.
Still not working? That's a job for a pro.
When to call a pro
The problem is still there after these checks. Anything inside the unit is a job for a pro.
Questions
Why is my furnace not heating?
Start with the simple checks: make sure the thermostat is set to heat and its batteries are fresh, the air filter is not clogged, and warm-air vents are not blocked by furniture or drapes. If there is still no heat, call a technician rather than opening the furnace yourself.
Source: energystar.gov
Why won't my furnace turn on?
After the thermostat and filter checks, a furnace that will not start is a job for a technician. ENERGY STAR lists checking the controls and the starting cycle as part of a professional tune-up. If you smell gas, leave the home and call your gas utility or 911 from outside.
Source: energystar.gov
Why is my heat pump not heating?
Make sure the thermostat is in Heat mode, not Auto, and that the filter is clean. Light frost on the outdoor unit in freezing weather is normal. If coils stay frozen, the unit keeps cycling on and off, or the room never reaches the set temperature, call an HVAC professional.
Source: bsesc.energy.gov
How often should I change my furnace filter?
The U.S. Department of Energy advises cleaning or replacing furnace filters about once a month, or as the manufacturer recommends. A clogged filter restricts airflow and makes the system work harder, so it is one of the first things to check when heat seems weak.
Source: energy.gov
Should I have my furnace checked every year?
ENERGY STAR recommends an annual pre-season check-up by a contractor. Because contractors get busy once winter arrives, it suggests having the heating system checked in the fall, before you need it.
Source: energystar.gov
Describe the problem
What kind of system is it?
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