Swapped old Booster Pump for New - now have way too much pressure.

[kilo_atx]

My original booster pump died on me after 7 years - F1RST CHOICE 3/4hp model WB075. I replaced it with a Pentair PB4-60.
I thought this would be like for like but the new booster pump is at least twice the pressure, enough to pull the backup valve on my Polaris 280 cleaner apart.
My first thought was I must be running 220v through a 110v pump... but the Polaris is wired for 220v as was the old F1RST CHOICE (Not sure what the retail name of this pump is - thats whats on the sticker...). I've attached pics of the pump specks both OLD and NEW. Anyone have any idea what I'm overlooking here?
thanks is advance

 

[ajw22]

Welcome to TFP.

The new pump is at least 20% more powerful when you compare the amp draw between them. Higher amps = more HP.

Polaris 280 manual is here - https://www.polarispool.com/-/media/zodiac/global/downloads/tl/tl-200.pdf

Do the wheel RPM check in step 4 and put in the blue or red restrictor disc to adjust the water pressure.

You can also unscrew the pressure relief valve to decrease water flow to the cleaner. Note: The pressure
relief valve should only be adjusted when a restrictor is installed.

 

[1poolman1]

First Choice is just re-branded Waterway.
To clear up mis-conceptions;
The old pump is a .75hp with a service factor (SF) of 1.67. Multiply - .75 X 1.67 = 1.2525 thp (total horsepower). You see that in the MAX LOAD amp rating.
The new pump is a .75hp with a service factor(SF) of 1.5. Multiply that - .75 X 1.5 = 1.125 thp (total horsepower). You see that in the AMPS SF (the same as MAX LOAD).
This confusing way of labeling pumps is one reason the DOE made sweeping changes in the way pumps and motors are labeled and marketed. I've already seen it in new pumps that I have installed and have to try to explain it to the pool owner. Now they require HHP (hydraulic horsepower) and WEF ( weighted energy factor) to be labeled so that you can make a better comparison of like for like. Pentair Intellflow pumps are now listed as 3hp when they used to be labeled 3.8 to 3.9 total horsepower. The label was different on virtually every pump I installed.
Polaris booster pumps have always been very powerful. Their design lets them move more water, or apply more pressure, at a lower motor horsepower. That's why they had to design the pressure relief into their wall fittings.

Your back-up valve likely had a small crack in the housing and the new pump just finally made it fail. That's how most of the back-up valves that I have replaced fail. Since new Polaris cleaners can be bought as a set of cleaner and pump, the pump is not the cause of the valve failure.