15 Minute Assessment

HVAC: Gas Heater

Gas heaters are usually paired with another heat source. Fireplace inserts and wall-mounted units that burn natural gas or propane are most common.

Gas flows through lines into the heater, where it’s lit by a pilot light or an electric starter. All gas heaters should also have a shutoff valve.

Most gas heaters vent to an outside wall. A blocked vent can send fumes back into your home. Ventless gas heaters can raise humidity in your home. Make sure humidity stays below 50%.


Every fall

Repair and replacement costs

Typical Costs

  • Inspect: $75 – $125
  • Repair: $175 – $900
  • Replace: $1,000 – $3,000

Life span


15-20 years

Steps to Assess Your Gas Heater


Step 1: To prevent fires and ensure easy access, clean the outside of your heater and the area around it. Inspect it for dents, cracks, and corrosion. Repair damage ASAP.


Step 2: Oen the heater and find the shutoff valve. If it isn’t inside the heater, check your basement or utility closet. Close the valve, then clean inside the heater with a brush or a vacuum.


Step 3:  Check the lines, valves, and components for corrosion, kinks, or cracks. If you find damage, call a pro. If you don’t find any issues, reopen the gas valve and close the panel.


Step 4: Check ductwork and vents for damage or blockages. If you have vented heaters, the vent should be on an outside wall. Gas fireplace inserts may vent through the roof. Clear any blockages.


Step 5: Start the heater. If it won’t start, look for a switch. If it still won’t start, the ignitor may be broken, or the pilot light may be out. If these fixes don’t work, call an HVAC pro.