You mentioned that a common furnace problem is that the pressure could be bad. What is a pressure switch, and where is it located?

Answer

The pressure switch is typically a round disc-shaped part with a hose connecting it to the inducer fan. When the fan kicks on, it creates suction if working properly. That suction pulls in the switch making an electrical connection that allows the next step in the cycle to commence.

Updated on April 2, 2018

Original Article:

Troubleshooting Common Furnace Problems With an HVAC Expert
By Dan Robbins
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