How to Set Up a Pressure Switch for a Goodman LP Furnace

Opening the Furnace

• Before inspecting the interior of your furnace, shut off the LP gas at the valve and disconnect the power at the circuit breaker or fuse box. You can remove the side panel from the furnace by unscrewing the bolts with a nut driver. Once the panel is off, locate the existing pressure switch in the upper left-hand corner. This small box-like part attaches to a flexible plastic hose that extends downward to a nozzle.

Removing the Old Pressure Switch

• Pull the flexible hose off of the nozzle on the pressure switch but leave the other end of the hose attached to the furnace. The two wires on the switch slide off with the metal connector attached to each wire. Once the wiring is disconnected, remove the switch by extracting the screws that hold it to the inside of the furnace.

Installing the New Switch

• Hold the new switch in place against the mounting holes and connect it to the furnace with the screws. Slide the two wires onto their respective terminals on the new switch once it is screwed securely to the furnace. The flexible hose slides onto the switch nozzle. Push the hose firmly onto the nozzle.

Closing Up the Furnace

• Before you can operate your Goodman furnace, you'll need to replace the cover panel. Hold the panel in place and secure it with the bolts and nut driver. Switch on the electricity at the breaker or fuse box and open the LP gas valve. Turning the ignition control to the "Pilot" setting lights the furnace. Adjust the control to the desired setting once the pilot ignites with a clicking sound.