I have a Carrier Weather Maker XFI and it is giving me a fault code of 3 2 , which says low pressure switch fault. Does anyone know how to fix this without bringing out a technician?

Do things you need to do.

1. Check the swicth by checking for 24 VAC on the terminal leads when the system calls for heat. Visually inscpt the switch, check hoses, etc. You can suck into the pressure swicth and see if the switch closes. You'll need a multi-meter.

2. check and see if the draft inducer motor is operational and providing back pressure to the switch. Does it spin?