Gas Furnace Pressure Switch Troubleshooting

The pressure switch fitting may have a restrictor inside do not remove.

Gas furnace pressure switch troubleshooting.

A gas furnace pressure switch closes to allow current to pass through and start the ignition of the furnace. Also the fittings that the tubing fit into should be clear. A furnace pressure switch is a safety device located near the draft inducer motor of a gas forced air furnace. Ensure the draft is above the required pressure.

The switch activates with air force pushing a plunger in the mechanism which closes the circuit. 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. 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. 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.

The pressure switch is an indicator of pressure problems in the furnace. A pressure switch is designed to sense the negative pressure created by the draft inducer motor during the furnace startup and. It should be clear. Here is a quick breakdown of the steps involved in replacing a gas furnace pressure switch once you have sourced your new part.

Check the tubing from the inducer. Other problems that could cause the pressure switch to not open are a dirty. The switch is there to prevent the furnace from running unless the correct venting air pressure is present. The pressure switch on a lennox g16 gas furnace monitors whether the air blower is in operation.

If the pressure switch is stuck it does not send enough power to the inducer and therefore the ignition sequence does not begin.