New Construction Started - Willis, TX (north of Houston)

[Duffatola]

The single bottom main drain with a 4" line going to the water feature and a 2" line going to the filter pump should be sufficient as long as you keep the filter pump line closed most of the time or only slightly open.

In other words, if I'm running the feature pump, close or limit the filter pump suction line/valve and if not using the feature pump, open the filter pump suction valve for more/better circulation?

Speaking of the feature pump, please advise regarding this plan.

 

[JamesW]

In other words, if I'm running the feature pump, close or limit the filter pump suction line/valve and if not using the feature pump, open the filter pump suction valve for more/better circulation?

I would leave the filter suction to the main drain closed most of the time.

Maybe only open it periodically to keep the water from being stagnant.

I would run the filter at about 20 to 25 GPM and use mostly skimmers.

The suction to the filter pump can be 2" or 2.5".

The returns to the bubblers can be 1.5" each.

 

[Duffatola]

Negative edge plumbing plan.

 

[JamesW]

I would use 2 check valves instead of just one.

Use Jandy 2.5 x 3" check valves.

I would put a 2.5 x 3" Jandy 2-way valve on the bypass.

For the returns, I don't see any reason to valve them separately.

 

[Duffatola]

View attachment 424643

https://www.pentair.com/content/dam/extranet/nam/pentair-pool/residential/automation/intellicenter/manuals---user-docs/intellicenter-users-guide.pdf

View attachment 424648

https://www.pentair.com/content/dam/extranet/nam/pentair-pool/residential/automation/intellicenter/manuals---user-docs/intellicenter-installation-guide.pdf

I tried to dumb this down to apply to my specific application. I think my plan is correct other than moving a check valve downstream of the filter?

 

[JamesW]

The check valve after the filter is if you have solar.

I would leave the check valve between the pump and filter.

I would do the pool main drain at 2.5" and not 4".

I don't see any reason to put valves on the pool returns.

The SWG position is good.

 

[Duffatola]

I would do the pool main drain at 2.5" and not 4".

Agreed, will revise.

I would leave the check valve between the pump and filter.

10-4

I don't see any reason to put valves on the pool returns.

My thinking was if there was an issue (specifically, a pipe break/leak) in one return, I could isolate it and still have a functioning return line until a repair could be made.

 

[JamesW]

Since you will be at high flow during Spa jet operation, you might want to put in a check valve bypass that allows water to bypass the heater at a specific pressure.

The heater needs 40 gpm.

At 40 GPM, the head loss is about 2 to 3 psi (7 feet of head is 3 psi)..

So, if you have a check valve on a bypass line that opens at 2 to 3 psi, the bypass is automatic.

2 psi cuts it a little close, so you might want a 3 psi check valve on the bypass.

A manual bypass valve should be installed across the heater when the pump flow exceeds 120 GPM (454 LPM).

See“WATER FLOW RATE” on page 14 (Table 1) for setting of the manual by-pass valve.

https://www.pentair.com/content/dam/extranet/nam/pentair-pool/residential/manuals/heaters/mastertemp/Manual-MasterTemp-472592-English.pdf

https://www.pentair.com/content/dam/extranet/nam/pentair-pool/residential/manuals/training/Sta-Rite%20Engineering%20and%20Design%20Manual.pdf/subassets/page19.pdf

https://www.praherplastics.ca/wp-content/uploads/2020/11/Praher-2021-Pool-Catalogue.pdf

https://www.jandy.com/-/media/zodiac/global/downloads/h/h0574300.pdf

 

[JamesW]

My thinking was if there was an issue (specifically, a pipe break/leak) in one return, I could isolate it and still have a functioning return line until a repair could be made.

You could change the plumbing at that time if necessary.

You can install the valves now, but it's not really necessary.

 

[JamesW]

For service, I would put a 2.5 x 3" Jandy 2 way valve on the infinity edge pump suction.

Since the trough/basin will be lower than the system, priming will take longer than normal.

Close the 2-way before opening the lid to keep the prime.



_______________________________________________________________________________________________________________________________

For the filter pump, I think that we determined that you would have 6 spa jets at 20 gpm per jet, which is 120 gpm total.

That's right at the edge of the limit for the heater.

A 3.5 lb. check valve bypass will reduce the mechanical erosion of the heat exchanger at high flow and it will give you better flow characteristics during spa jet mode at 120 gpm.

 

[Duffatola]

I would use 2 check valves instead of just one.

Use Jandy 2.5 x 3" check valves.

I would put a 2.5 x 3" Jandy 2-way valve on the bypass.

For the returns, I don't see any reason to valve them separately.

View attachment 424726

Why 2 check valves? Backup in the event one fails?

If I put a single valve on the bypass, I won't be able block flow from the filter. The idea of the bypass is to increase flow for maximum negative edge effect by not running through the filter. It seems to me I could either use one valve before the filter and after the Tee or a 3-way valve after the filter where the bypass connects.

 

[JamesW]

Why 2 check valves? Backup in the event one fails?

Yes, if one fails, the pool will empty into the basin until the water in the pool is the same level as the basin.

If I put a single valve on the bypass, I won't be able block flow from the filter.

No need to block the flow to the filter.

Just use a 2.5" or 3" bypass line and open the valve for full effect.

Some water will go through the filter and some will go through the bypass.

 

[JamesW]

If we assume a flow of 200 GPM for the infinity edge with the bypass open, about 160 GPM will go through the bypass and about 40 GPM will go through the filter because the head loss would have to be the same.

If the bypass around the infinity filter is 10 feet of 2.5" PVC pipe, the head loss is about 0.754 feet at 160 GPM.

 

[Duffatola]

6/16 - Day 14
Gunite Day 2 - 7:00 a.m. - 5:00 p.m. The heat was brutal. "Feels like" temp near 108 degrees. These guys (8) were machines. They were hoping to finish but weren't able to.

 

[Duffatola]

For the filter pump, I think that we determined that you would have 6 spa jets at 20 gpm per jet, which is 120 gpm total.

That's right at the edge of the limit for the heater.

A 3.5 lb. check valve bypass will reduce the mechanical erosion of the heat exchanger at high flow and it will give you better flow characteristics during spa jet mode at 120 gpm.

I'm not exactly sure where the CV bypass will be located. I inserted it on the bypass line before the heater but I'm not sure that's correct. Furthermore, the size/rating of check valves never dawned on me. What about the rest of the CV's on the filter system?

Will the check valves on the negative edge and water features systems need to be sized as well?

 

[JamesW]

For the large lines, use a 2.5" X 3" Jandy check valve.

The large 2.5" x 3" dimension is designed to easily connect with the Jandy Pro Series 3HP Stealth Pump and can handle flow rates up to 170 gallons per minute with minimal head loss, making it great for spas and water features that require high flow rates.

Pool Check Valve: Jandy Check Valve | Jandy

Looking for a Pool Check Valve? Find the Jandy Check Valve for the Perfect Pool Experience. Buy Now w/ a Pool Pro Near You!

www.jandy.com

The 3.5 lb (psi) check valve allows water over 3.5 PSI (differential) to bypass the heater.

The red dots show where the 3.5 lb. check valve goes.

You have to create an additional bypass that is parallel to the heater and inside the three-way valve and inside the other check valve.

This has to be a spring check valve with a 3 to 4 lb spring and not a regular check valve.

For the other check valves, I used a 5 for the 7305 model and a 7 for the 7307 model.

 

[JamesW]

Hayward has some 3" and 4" commercial check valves that are bigger that might work, but they are ball check valves, which might not be as reliable.

The Jandy is rated to 170 GPM, which should be ok for your application.


Here are some strainers you can use for the sheers if you don't like the Jandy strainers.

 

[Duffatola]

@JamesW

Freakin' check valves are another science altogether. I'll need to confirm the PB will agree to use Jandy valves since the are married/authorized Pentair. After signing the contract a couple of months ago, they indicated they were getting what ever valves (Pentair or Jandy) were available. Regardless, it sounds like the Pentair XF 263060 is a "one size fits all" valve. This is the only technical info I could find. If using this valve, would it be acceptable for all check valve needs for all three (filter, neg edge and feature) systems?

 

[JamesW]

That will work except for the heater bypass check valve, which needs to be a 3 lb spring.

https://www.pentair.com/content/dam/extranet/nam/product-related/product-manuals/pool-and-spa-equipment/valves/FullFloXF%202Way%20and%203Way%20Diverter%20Valve%20and%20Check%20Valve%20Installation%20and%20Operation%20Instructions%20English.pdf

 

[JamesW]

Pentair does make a Bypass check valve, but the spring is 12 lb, which is way too much.

https://www.pentair.com/content/dam/extranet/nam/pentair-pool/residential/parts-sheets/heaters/ultratemp-heat-pump.pdf

39.....R172305 WATER BYPASS CHECK VALVE

https://www.pentair.com/content/dam/extranet/nam/pentair-pool/residential/manuals/heaters/ultratemp/ultratemp-heat-pump-installation-and-users-guide-en-fr-sp.pdf

The Pentair Ultratemp heat pump uses the 12 lb. spring bypass, but the pressure never gets to 12 psi, so I don't see where it would ever do anything.

From the chart, 9 psi is the highest pressure.

You can get the 12 lb bypass, but it seems to me that it won't help.

Maybe check with Pentair and ask them what spring strength should be used if you were going to do a spring bypass on the Mastertemp.

You don't have to do a spring bypass on the Mastertemp as the flow will not exceed 120 GPM as specified in the manual.

However, in my opinion, putting anything over 60 GPM is unnecessary and it can create extra wear on the heater components.

Below is the MasterTemp internal bypass that all of the water need to flow through when the heater is not on.

When the heater is on, part of the water flow goes through the bypass and part goes through the heat exchanger, which has a thermal regulator at the exit.

So, you're trying to push 120 GPM through a relatively small internal bypass, which is a spring bypass, and a small thermal regulator.

The extra bypass relieves the heater's internal bypass from excessive flow.