Thanks for the post!

That's strange that it won't shut off now, even after replacing the Pressure Switch. I have to ask, are you sure you installed and wired the Switch properly? This would be the first questions that comes to mind.

The Switch has copper contacts that mechanically close and open the circuit, so if it's wired correctly and you know that the on/off switch is disconnecting the circuit, there is another problem here.

The second question I would ask is regarding the Motor. If this is the case then it's best to have an electrician diagnose it.

What is the model number of your Central Pneumatic unit? And, what is the part# of the Pressure Switch you replaced the original with? This will help.

- MTR