Can You Bypass A Pressure Switch On A Gas Furnace

The pressure switch on a lennox g16 gas furnace monitors whether the air blower is in operation.

Can you bypass a pressure switch on a gas furnace.

Suck on the power hose and then check the switch again using the ohmmeter. Remove the pressure switch hose s after carefully noting where it is connected if there is more than one hose remove and reinstall them one at a time. Sometime the switch itself the part buried within can fail. This would only be d.

You can however test with a continuity tester testing with pump off and then pump on. This might free the switch from sticking. In no way do i recommend you attempt bypassing switch and should only be done by qualified technician. It doesn t take much pressure so don t blow too hard.

If a pressure switch is not jumpered correctly the furnace will not turn on at all. As long as the induced draft blower runs and there isnt a blockage in the flue then you should be fine. Honestly without seeing it in person i wouldn t be all gung ho about bypassing it. After all this the furnace should fire right back up.

Next take off one of the power hoses and blow on it. How to jump or bypass pressure switch on a furnace. First turn the power of the furnace off. When you do this you should hear a clicking noise.

If your lennox does not activate normally during the ignition sequence try running a quick bypass of the pressure switch to determine if it is the problem. On newer furnaces on a call for heat the ifc checks the pressure switch. By this point on an 80 efficiency furnace if you haven t found the culprit you will have to put on your best thinking cap because the issue could be any number of things including a bad board loose or bad wire connections or a bad pressure switch. With pump on should be closed allowing continuity.

If you are working on a 90 condensing furnace move to the condensate drain. So go ahead and put the hose back on put the access panel back on the furnace turn up the thermostat to its highest setting. The switch activates with air force pushing a plunger in the mechanism which closes the circuit. Now use the ohmmeter to check whether the pressure switch is functioning properly.

Make sure the hose is not obstructed inside. Take off the end so you can blow through it to the pressure switch.