Buzz
Your gas furnace might have ceased functioning, but there's no need to immediately seek professional repair. If you've shut off your furnace for the summer or it's not heating adequately, it could be due to insufficient gas pressure. Adjusting the gas valve inside the furnace can address this issue. While most furnaces feature a single valve, two-stage furnaces have separate high and low-pressure valves. This adjustment is relatively simple and can be completed within minutes. However, if you detect gas leaks or other serious issues, it's advisable to contact a licensed heating and cooling specialist.
Procedures
Accessing and Igniting a Furnace
Remove the front access panel from the furnace. On many furnaces, this panel is secured by four screws positioned near its corners. Use a Phillips screwdriver to turn them counterclockwise. Once the screws are removed, lift the panel off the furnace. If there are no screws, simply lift the panel to detach it. Note that the front panel may include vents or instructional stickers for easy identification.
Locating the Gas Valve Box
Restarting the Pilot Light if Necessary
Attaching a Manometer
Removing the Outlet Port Cap
Connecting a Manometer Hose to the Manometer
Connecting the Manometer to the Outlet Port Using a Tube Adapter
Adjusting the High-Pressure Valve
Checking the Recommended Pressure Setting
Activating the Manometer to Obtain an Initial Pressure Reading
Setting the High Pressure to the Recommended Level
Adjusting the Low-Pressure Valve
Finding the Shorter Valve on Your Furnace
Lowering the Heat Using the Thermostat
Setting the Low-Pressure Valve to the Recommended Level
Completing the Furnace Adjustment Process
Helpful Tips
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If your furnace refuses to start, check the control knob on the gas pipe leading to your furnace. If it's perpendicular to the pipe, turn it to allow gas flow.
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Monitor the thermostat to ensure it's functioning correctly. Verify that the displayed temperature matches the heat output of the furnace.
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If you encounter difficulties adjusting the valve or notice any issues with your furnace, contact a heating and cooling technician in your area to ensure the furnace's safety.
Important Warnings
- Exercise caution around an active furnace to prevent burns or electric shock. Avoid contact with exposed electrical wires and handle gas valves carefully.
- Reigniting the pilot light when the furnace is off can result in a fire hazard. Ensure all gas is drained from the line before relighting the pilot light.
Required Items
- Phillips head screwdriver
- Flathead screwdriver
- Manometer
- Manometer hose
- 1⁄8 in (0.32 cm) MPT adapter
- Long-stem lighter (optional)
