Pentair SuperFlo installation update

[reel-2-reel]

I bought a Pentair Superflo 2-speed pump to replace a very old, single-speed that wouldn't run on seasonal startup. I got it from Amazon and I didn't realize, until after installation, that it didn't come with the unionized fittings. I connected it by using threaded PVC. It had a small leak at both the out joints from the pump and into the multi-valve, so I re-did them. There is still a small leak on the around the PVC fitting coming out of the pump. I don't know if by using the unionized fitting the leak will stop.

I have an issue that may be related to the leak but I'm not sure. One morning, I discovered that although the pump was still running, there was no water movement. The pump was on low speed. I re-primed and it ran without incident until today. I switched to high speed for several hours during maintenance. Afterward, when I switched back to low speed, the filter basket evacuated of water. It appeared to go "upstream" toward the pool. When this happened, the pump lost prime and failed to circulate water. I went back to high speed and it self-primed.

I like this pump despite this issue. The low speed is very quiet and move a substatial amount of water. Any advice is appreciated.

 

[JasonLion]

Given that you know there is a leak, that leak is almost certainly the cause. It doesn't take all that much air getting in on the suction side to prevent priming on low speed. Alternatively, a leak on the pressure side would allow the pump to drain down between uses and low speed might not be able to prime.

 

[reel-2-reel]

Given that you know there is a leak, that leak is almost certainly the cause. It doesn't take all that much air getting in on the suction side to prevent priming on low speed. Alternatively, a leak on the pressure side would allow the pump to drain down between uses and low speed might not be able to prime.

It is a leak on the pressure side. The pump had been running constantly, not turned off.

 

[Perry Whitlock]

I installed the same pump on my pool a couple of months ago and changed from a sand filter to a cartridge filter about a week after putting in the new pump. I agree with Jason, you have a suction side air leak and so did I and did not know it. My leak was very slight and I could actually stop it for 3 or 4 days by putting gel type shaving cream around the suction joints and valve stems. At the higher speed, the pump seems to pass the air thru better and did not loose prime. When my cartridge filter came in and I installed it, I was bleeding lots of air out of it every day. It was then I knew I had a suction side leak. My pump puts up 20# pressure on high and 4.5# pressure on low speed. When I had a large amount of air trapped in the filter and running on high (20#) and went to low speed (4.5#), the air would expand rapidly and blow the water out of my pump. A couple of times when I turned it off when running on high it blew back so hard it flipped my pool skimmer basket upside down. I ended up replacing the suction piping and valves and now all is well. If you go this route it would be a good time to install the unionized fittings. You will love this pump when you get the kinks worked out of the system.

 

[reel-2-reel]

Thanks, Perry.