HVAC Problems

[WTJackalope]

My central heating unit has developed an annoying problem. The blower door pressure switch will work sometimes and other times I have to jiggle the blower door to get the unit to fire up. I have replaced the pressure switch within the last month and had no problems for a couple of weeks, but then the same problem occurred. The unit is inside a door in my garage. It seems like the colder it is outside the more it doesn't work right.

I'm posting here to see if anyone else has had this problem and discovered a fix..... before I'm forced to call a HVAC repairman.

Thanks in advance.

 

[Oildudeny]

How are the connections at the switch and control board of the HVAC system? If you have good solid connections and feel the new switch is faulty, take the wires off the switch and twist them together this will act as if the switch was closed completing the circuit. The unit should operate correctly, if it doesn't the circuitry on the control board that corresponds with the switch may be the culprit.

 

[mk378]

Are you talking about the big blower that moves air into the house, or the burner draft induction system?

 

[WTJackalope]

When I jiggle the door the gas lights up, followed by big blower coming on shortly thereafter

 

[mk378]

You can probably bend something so that the button on the switch gets pressed a little more fully when the door is closed.