Gas Furnace Pressure Switch Troubleshooting

A gas furnace pressure switch closes to allow current to pass through and start the ignition of the furnace.

Gas furnace pressure switch troubleshooting.

If the pressure switch is stuck it does not send enough power to the inducer and therefore the ignition sequence does not begin. Also the fittings that the tubing fit into should be clear. The pressure switch on a lennox g16 gas furnace monitors whether the air blower is in operation. Other problems that could cause the pressure switch to not open are a dirty.

The switch activates with air force pushing a plunger in the mechanism which closes the circuit. Here is a quick breakdown of the steps involved in replacing a gas furnace pressure switch once you have sourced your new part. The switch is there to prevent the furnace from running unless the correct venting air pressure is present. The pressure switch fitting may have a restrictor inside do not remove.

The pressure switch has a pressure at which it closes which is typically negative. When the pressure switch opens the gas valve closes and the furnace starts another ignition cycle because the pressure switch closed after that 1 2 second glitch. 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. Check the tubing from the inducer.

The pressure switch is an indicator of pressure problems in the furnace. A furnace pressure switch is a safety device located near the draft inducer motor of a gas forced air furnace. It should be clear. 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.

Lennox pressure switches and carrier pressure switches are two popular furnace pressure switch brands but it is best to purchase based on your furnace model number.