In an earlier post I was asking for some assistance with my gas furnace that kept shutting off. One day last week I was watching it cycle and when it shut down I saw the error code that = Pressure Switch. So I pulled the tube and sucked and the switch activated. Watched the furnace cycle and it shut down again. Hmmm??
Took a block of wood and smacked the switch and it has been working ever since!
Of course I had the HVAC guy come out and of course nothing was wrong. Told him what I had done and he thought I may have dislodged some dirt/dust. He didn't want to start replacing parts so he checked the unit and was satisfied.
I do have the info on hand for a replacement switch if necessary.
So wood is good!!