60146 PRESSURE SWITCH HSU MHU080,0.40" WC

Before Replacing the switch please take a minute to check these instructions that other customers have found helpful to get back up and running.

The very first question is always, is this connected properly?
Have the leads been reversed leads?
Has the hose barb on the exhaust blower fan been cleaned out?

• These barbed fittings get clogged and will cause the switch not to operate.

I am getting a 3-flash code; does that mean my pressure switch is bad?

Most likely not, the pressure switch being faulty is the least likely issue.

We recommend that you please execute the following tests to try and eliminate all possibilities other than the switch.
First, pull the vacuum tube off the pressure switch and blow into it.
If it does not have good flow or no flow at all, then clean out the vacuum hose connector with a 5/64in drill bit.

If it is not that, then turn the heater on with the vacuum hose connected to the pressure switch.
Turn the thermostat on then Create Suction on the hose to create a vacuum and pinch the hose to keep the vacuum pressure.

If the heater fires up, reconnect the hose to the hose connector on the vent motor.

Once that is done, if this shuts the heater down then you have something blocking your exhaust.

If after these steps the heater still does not function, then replace the pressure switch.