new pump questions

[semenzato]

Thank you and sorry if I didn't explain very well. I am thinking of replacing the entire pump, because it's fairly old and I am not sure that replacing the motor only will fix the problem.

Also, I am thinking of replacing the pump with a 1-speed pump (the 1-speed Hayward Super Pump). I am not sure that a 2-speed pump will work properly because I don't know if, at low speed, the flow to the solar panels in the roof will be sufficient to prevent gravity from pulling air down into the system.

My uncertainty is that I am replacing a 3/4 HP pump with a 1.6 SF with another 3/4 HP pump but with a 1.0 SF. In other words, it's possible that the old pump has been running at more than 3/4 HP---hard to tell. As far as I understand, a 3/4 HP motor with 1.6 SF is really a 1.2 HP motor.

Thanks again!

[mas985]

The wet end of a pump can well out last the motor so replacing just the motor should fix your problem based upon the symptoms you described. You can buy a new pump if want to but I was suggesting that you don't have to if you don't want to. 12 years is a long time.

If you are replacing the entire pump and motor, then the HP and SF really don't matter much. Either will work just fine. HP and SF only matter if you are replacing just the motor and using the same wet end.

As for two speed, I have a two speed pump with solar on a two story roof. I run solar on high speed and use low speed when solar is not required or during the winter. That alone saves quite a bit on energy costs so don't dismiss a two speed so quickly.

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Most kind of you, thanks. The two-speed suggestion is very good.