Eleven Tips for Adjusting a Furnace Gas Valve

by DoItYourself Staff

A furnace gas valve supplies the burners of the furnace with gas. This flammable gas is supplied once the burners heat up enough so as to allow combustion. Here are eleven tips to help you adjust a furnace gas valve.

1. Check the Pressure

It is recommended that you do not adjust your furnace at a pressure other than that recommended by your manufacturer.

2. Follow the Right Procedure

The knob that controls the valve should be turned “on”. The necessary thermostats should be turned up so that the furnace fires. The pressure on the manometer should be checked. To make adjustments, the cap that covers the pressure regulator screw should be located and removed. You can then make adjustments to the pressure in the upward or downward position.

3. Check the Pilot

If your furnace does not produce any heat at all it could be because your pilot needs to be relit and the gas valve is not open. In some cases the thermostat could not be functioning properly. Check the pilot and valve.

4. Call for Help

If your gas furnace is not working, instead of trying to adjust gas valve of a furnace, call in a service technician to find out what the problem is.

5. Clean the Crosslighter

If there are multiple burner tubes, before adjusting the burner, pull the burners and ensure you clean the crosslighter.

6. Adjust the Regulator

Very often the gas pressure is too low. This could be because the gas valve or regulator may not be adjusted properly. As a result of this the flame that is provided is unsafe and inadequate. This problem can be rectified by adjusting the regulator. You would however have to know what the problem is caused due to. Boosting the pressure at the valve level is not advisable as it might be unsafe.

7. Ensure Optimum Settings

For your heating system to heat effectively you have to ensure that it can be adjusted well enough so that it can run continuously even in the coldest weather.

8. Adjust the Flow of Gas

The flow of the gas can be adjusted with the help of a screw that is beneath the big screw or the cap screw. By turning the screw which is available for pilot adjustment counterclockwise, the flame can be increased.

9. Adjust the Pressure

If you turn the adjustment screw in a clockwise direction it would give more pressure. Similarly turning it in the anti clockwise direction would give less pressure. When you are trying to make these adjustments on your own, make sure you do not turn the screw more than ¼ turn either way.

10. Check the Sequence

Check the sequence followed by the furnace right from the time it starts up to figure out if you have a faulty gas valve. Do not try and adjust the valve if you hear a “hissing” sound while trying to ignite the gas.