I don't think I have ever seen a high pressure switch fail where it cut off prematurely…However I have seen them fail in the stuck open position where they won't allow the compressor to come on…

This usually only happens in cases where the operator keeps resetting HPF faults without fixing the problem…

If you are sure you have full water flow, then I might suggest you do an acid flush of your condenser coil…At 7 years of age it's time…

Lots of info here on the site about it  

Steve~

Post edited 3:21 pm – July 23, 2011 by Steve Pooler

Here's the deal…First, chlorine tablets may kill scum, but I don't think they will do anything to hard scale…

Scale acts like an insulating blanket preventing good transfer of heat to the seawater.

Normal system head pressure is somewhere between 200 to 275 psi depending on the seawater temp & heat load on the system.

The high pressure switch does not cut off until 425 psi.

Without gauges we don't know how high your's is running, but we do know you have been tripping the switch, and now you may be at just below where it trips…

The higher that pressure runs due to poor heat transfer…The harder the compressor has to work against it and the more amperage it will draw.

This stresses everything in the system to it's limits including electrical connections…

It's your call, but If I didn't have gauges to see where it actually is running (lower is better) I would acid flush the unit…

It & everything related including you will likely be much happier  

Steve~