Inconsistent success priming new pump & losing prime once established


New member
Jul 4, 2020
Hi everyone, thank you in advance for your help and advice. We recently replaced our 1 HP, 1 speed Hayward pool pump with a Hayward 1.65 THP Max Flo VS pump. We’ve had issues getting the pump to prime on a consistent basis, and once it does it prime and lowers kWh it will randomly lose suction power and no longer pull water through the filter. The water level of the pool is consistent and there are no bubbles coming from the jets when it is running properly. Also, I have not seen a “low flow” indicator light, referenced in some threads in this forum, come on. We have just been letting the pump run on speed level 1 and manually increasing it for a few hours each day as I’ve not yet found in my previous research the best schedule for which to program the pump to run at different speeds for our pool size. As of the time of writing this post I have not been able to get the pump to prime for over 16 hours. It’s the weekend, the Fourth of July, and hot as blazes and our local pool companies are all closed. Thanks for your input! Happy 4th of July!


TFP Guide
Hello and Welcome to TFP!!

I suspect you have a suction side air leak.
when you first turn on the pump, it starts at 100% speed, right?
When it looses prime, is the pump basket empty or full of water?
If the pump basket is empty or has a lot of air in it, start by removing the lid and lubing the cover oring. If that doesn’t work, come back and we can offer some more suggestions.