Rebuilding the Pool Plumbing and now working on the PB4-60 and Polaris 380

[jhill28590]

Over the last few years I have replaced most of the 1-1/2 inch poly pipe with 2 inch PVC in our 34K gallon vinyl lined in-ground pool. It is now mostly schedule 40 with some schedule 80 at critical locations. There is also some CPVC at the heater. The flow rate is 70 GPM with both simmers and inlets open.

I am finding almost no design information about the new PB4-60 and Polaris 380 pressure side cleaner. I'm looking for pressure requirements, pump performance graphs, flow rate requirements, and the like. The pressure at the pickoff for the booster pump is around 3 to 4 PSI.

There is a posting on this site that indicates that a Polaris 380 needs between 28 and 32 PSI at 15 GPM. But without a little more information I can't confirm the correctness of the plumbing design. The big question at the moment is keeping the booster pump happy. With all the changes the back pressure of the pool is significantly reduced to around 3 to 4 PSI.

I would like to use 5 feet of Polaris 3/4 inch flex hose on the input to limit the bend radius. But I am unsure how much length I can afford without risking cavitation as the flow rate increases. I have learned (the hard way) the system needs the Polaris 380 in place to limit the flow rate. The Hayward documentation mentioned having to have the cleaner in place. With a booster pump flow rate of 27 GPM and five feet of hose the input pressure goes to zero. I am concerned this will cause cavitation. But I am just beginning to understand the basics of fluid dynamics and cavitation.

I'm also thinking of installing the quick disconnect device with an orifice to provide a minimum back pressure to limit the flow rate to prevent cavitation with the Polaris 380 not in place.

 

[1poolman1]

Just supply the Polaris pump and let it do the rest. There is no published info on the supply requirements of them.
A tee in the return line after the filter is usually all that us needed. I have found that having the tee in a horizontal line as opposed to the vertical going into the ground works best.
If you are using a VSP, obviously it needs to be at a speed that keeps the pipe full. I like to use a tee instead of a 90 as the last fitting going to a vertical pipe. Put a 3/4" threaded reducer bushing in the horizontal of the tee and feed the booster pump from there. Allows for a reduced flow to still keep the booster full. If you can't do that, put the tee close to the last 90. They only cavitate when there is no restriction on the output, like the cleaner not connected.

 

[generessler]

I'm not an expert, but my experience and reading of the documents is that if you have the blue restrictor plate installed in the return fitting as required, the pump is happy as long as there's enough pressure to guarantee a prime at startup (i.e. water gets to the inlet). The back pressure from the restrictor prevents cavitation as well as over-current draw of the pump.

I'm including a troubleshooting doc that has the 28-32 psi figure.

My system runs at ~5psi with the VSP. I'm using 3 feet of the Polaris flex supplied with the pump on the inlet. No issues. Runs quiet and reliably.

Keeping the 380's hose untangled is a different story If you have any tips on that, I'm listening!

 

[1poolman1]

I'm not an expert, but my experience and reading of the documents is that if you have the blue restrictor plate installed in the return fitting as required, the pump is happy as along as there's enough pressure to guarantee a prime at startup (i.e. water gets to the inlet). The back pressure from the restrictor prevents cavitation as well as over-revving of the pump.

I'm including a troubleshooting doc that includes the 28-32 psi figure.

My system runs at ~5psi with the VSP. I'm using 3 feet of the Polaris flex supplied with the pump on the inlet. No issues. Runs quiet and reliably.

Keeping the 380's hose untangled is a different story If you have any tips on that, I'm listening!

Hose tangling is usually an issue with bad swivels. Sometimes, when the cleaner is taken from the pool for swimmers it is coiled in a nice area. Very bad. The hose will take a "set" with curves that can't be removed and that will cause tangling.

As a side point, electric motors can't over-rev. Single-speed motors can only spin at a fixed rate based on the frequency of the input power (60 hz in the US). The noise you hear when a booster pump has no cleaner attached is cavitation.

 

[generessler]

Hose tangling is usually an issue with bad swivels. Sometimes, when the cleaner is taken from the pool for swimmers it is coiled in a nice area. Very bad. The hose will take a "set" with curves that can't be removed and that will cause tangling.

As a side point, electric motors can't over-rev. Single-speed motors can only spin at a fixed rate based on the frequency of the input power (60 hz in the US). The noise you hear when a booster pump has no cleaner attached is cavitation.

Hose tangling is usually an issue with bad swivels. Sometimes, when the cleaner is taken from the pool for swimmers it is coiled in a nice area. Very bad. The hose will take a "set" with curves that can't be removed and that will cause tangling.

As a side point, electric motors can't over-rev. Single-speed motors can only spin at a fixed rate based on the frequency of the input power (60 hz in the US). The noise you hear when a booster pump has no cleaner attached is cavitation.

Yes. Brand new Polaris and hose. Brand new booster pump. Everything clean. Swivels fine. Pressure fine. Floats fine. Never coil the hose. In fact it's seldom removed from the pool. Tried with restrictor and without. Various jet nozzle settings. Sometimes it goes a few days in a row with no problems. Then it gets confused again. I also have an old one (14 years and restored with many new parts) that actually seems to work a bit better.

I remembered the wrong word. Meant "over-current." From the manual: "This pump must have minimum outlet pressure of 45 psi. Lower pressure may cause an over-current motor condition."

 

[1poolman1]

Yes. Brand new Polaris and hose. Brand new booster pump. Everything clean. Swivels fine. Pressure fine. Floats fine. Never coil the hose. In fact it's seldom removed from the pool. Tried with restrictor and without. Various jet nozzle settings. Sometimes it goes a few days in a row with no problems. Then it gets confused again. I also have an old one (14 years and restored with many new parts) that actually seems to work a bit better.

I remembered the wrong word. Meant "over-current." From the manual: "This pump must have minimum outlet pressure of 45 psi. Lower pressure may cause an over-current motor condition."

I think its something about the newer hoses. I've been fighting mine for a year or so. I've been to every Polaris school, made every adjustment I can, and it still tangles occasionally. It was tangled 3 days ago. Didn't touch it. Tangle came out yesterday. Tangled again today. Pool's clean so I'm not fighting it

 

[HermanTX]

Keeping the 380's hose untangled is a different story If you have any tips on that, I'm listening!

The previous owner had purchased a new 280 about a year before we purchased the house & pool. I was fighting the tangles and after reading about hose set up and lengths, I readjusted everything. I recut the length of the leader hose to match depth, then made the 2 main hoses the same length and put a swivel in between. So basically have from the wall connection:

A short hose from the over pressure valve/connector to the inline filter - the inline filter has a built in swivel
Main hose - length is x
A swivel
Main hose - length is x
A swivel
The Leader hose which has the back up valve - length is y (to match depth)

Each main hose has floats as needed and spaced out
The overall assembly from the wall connector to the cleaner is equal to the max distance the cleaner has to travel plus 6 inches

Originally, this was only 1 swivel on the main hoses and the length was like 3 ft longer than maximum distance the cleaner had to travel

After this, I have had minimum tangles (mainly in winter when hose remains in pool) and the cleaner is actually able to pull out any curling of hose when it travels to maximum point on pool.

The hose and cleaner stays in pool year round with exception when lots of people swimming and that is only over a short period of time. When it does come out, I have a place to stretch it out without anyone tripping over it.

 

[generessler]

Thanks for all this advice. Mine generally does fine except when it turns back on itself into area of the return on the pool wall. Often it actually climbs up over the return and neatly wraps the hose around itself. After that it has about a 50/50 chance of pulling the tangle apart itself.

I just noticed that the troubleshooting sheet mentions the option of putting a 90 in the return fitting. That might help if the leg points straight up. It might block the loop-the-loop behavior that's causing most tangles. For $4.50 at Lowes seems worth try.

I also have some extra swivels. I think I'll add a couple.