"Always on" return path to Spa

[gdo]

My return path is shown in the diagram below. After the SWG, the water is split in 2 branches: one that goes to the valve that gets actuated through the automation system (EasyTouch) when switching between pool & spa modes, and another one that bypasses that valve and allows for a continuous flow to the spa, no matter what mode the system is in.

There is a manual valve that can control how much flow should go through this alternate path, and it currently is "full open".



I'm trying to understand the reason for this design:
- What is the purpose of always allowing some water flowing towards the spa? Is it to ensure a minimum amount of turnover even when the spa isn't being used?
- What should the manual valve (number 1) be set to? Are there times when I would want that valve to be completely closed?
- Why do we need 2 check valves in those specific locations? In particular, a pool guy who came to the house disabled the check valve number 2 by rotating it 90 degrees, claiming it had no purpose. For more context, these 2 valves are at the same height, and higher than the pool/spa water levels. I'm not sure what would cause water to come back up requiring the valves to prevent back flow.

Thank you in advance for your enlightenment!

 

[Jimrahbe]

gdo,

The line is called a make-up line and is used to control the spa overflow when in the spa mode.

Without the spa spillover, the spa would never get any fresh water and would soon turn into a cesspool...

The continuous spa spillover is a pretty standard way to build a Pool/Spa when there in no automation.

With your EasyTouch, there is another option. The EasyTouch has a "spillway" function. It is easy to set up and you can schedule it to run a couple of times a day for 30 minutes or so, to keep the water in the spa fresh. If you decide to use the Spillway function, then you would shut off the manual valve that currently controls the spillover.

In the Spillway mode the EasyTouch moves the Intake valve to suck water from the Pool and sets the return valve to return the water to the spa. Instant spillover.

Thanks,

Jim R.

 

[gdo]

gdo,

The line is called a make-up line and is used to control the spa overflow when in the spa mode.

Without the spa spillover, the spa would never get any fresh water and would soon turn into a cesspool...

The continuous spa spillover is a pretty standard way to build a Pool/Spa when there in no automation.

With your EasyTouch, there is another option. The EasyTouch has a "spillway" function. It is easy to set up and you can schedule it to run a couple of times a day for 30 minutes or so, to keep the water in the spa fresh. If you decide to use the Spillway function, then you would shut off the manual valve that currently controls the spillover.

In the Spillway mode the EasyTouch moves the Intake valve to suck water from the Pool and sets the return valve to return the water to the spa. Instant spillover.

Thanks,

Jim R.

That makes total sense! There is indeed a "Spillway" function! Thank you Jim!

BTW, what are your thoughts on the existence of the 2 check valves?

 

[Jimrahbe]

gdo,

Most systems only have one check valve. The way your plumbing is set up it appears you need two of them. It has to do with where the make-up line is plumbed in.

The check valves prevent a raised spa from draining back into the pool when the pump is off. We see this problem very often when the check valve fails or get dirty, etc..

If you use the Spillway function, both check valves could be removed if they are an issue.

Thanks,

Jim R.

 

[gdo]

gdo,

Most systems only have one check valve. The way your plumbing is set up it appears you need two of them. It has to do with where the make-up line is plumbed in.

The check valves prevent a raised spa from draining back into the pool when the pump is off. We see this problem very often when the check valve fails or get dirty, etc..

If you use the Spillway function, both check valves could be removed if they are an issue.

Thanks,

Jim R.

Got it. Thank you Jim. That was super helpful!