Testing Furnace Pressure Switch

Check for obstructions in the hose.

Testing furnace pressure switch.

If you see anything clean it out. Probe one lead of the pressure with one lead of your meter while touching the other lead of your meter to. The switch is being tested to check if it s closing when the diaphragm is pulled in. Ensure the draft is above the required pressure.

With a manometer or magnahelic. A multimeter is used to test the pressure switch and check the continuity of the switch whether it is closed or it is opened. The switch wires have to be removed first. A multimeter will be needed to test the switch for continuity.

To test the pressure switch use a multi meter and measure the continuity of the switch as it opens and closes. Hook a manometer to the tubing and check the draft from the heat exchanger in inches w c. The pressure switch has a pressure at which it closes which is typically negative. How do you test the gas furnace pressure switch.

Turn off the power to the furnace by switching off the disconnect switch located near the furnace. Turn off the power. Inspect the pressure switch hose. Set your meter to volts ac turn your furnace on so it is calling for heat.

If there is no disconnect. To do this the pressure switch wires are removed and the furnace turned on. The draft inducer should start.