Question on plumbing for SWG

[Quinten]

Looking at converting to a salt chlorine pool and I'm trying to determine the plumbing for the SWG cell. Can any SWG cell be mounted vertically? I don't have much space to work with before running into a lot of valves and junctions that I would want to leave as they are. There is also a backflow device or check valve (not sure what it is called) that was added when solar was put in several years ago. I was planning on installing the SWG cell vertically where the backflow/check valve is and placing the backflow valve vertically opposite the SWG cell.

Any issues with the backflow and SWG being mounted vertically and is it important is it to keep the backflow valve plumbed in?

 

[ajw22]

Some SWG's can be mounted vertically. What is important is positioning of the flow switch in the horizontal or upward water. Check the manufacturers installation instructions of the ones you are interested in.

Using a SWG does not require a check valve the way a tablet chlorinator does. The SWG does not create acidic water.

 

[Quinten]

Thanks for the quick reply! This forum is great! I'm wondering about the flow switch placement though. In this picture from discountsaltpool.com the CircuPool-RJ-30 shows the vertical mounting however isn't the flow switch in this picture in the downward vertical position? Also the existing check valve is for the solar heater... is that necessary?

OOPS!!!... Now that I'm looking at this is looks like I was seeing the flow switch as after the cell where it is actually before and installed how you mentioned! My plumbing flows right to left and I was thinking the same here but it is flowing left to right.

Still question about the check valve for solar heating.

Thanks

 

[Oly]

The CircuPool systems can be mounted vertically and the flow switch can follow the vertically placed cell as per their instructions on page 15.
Yes the insert from the pic you posted shows the flow switch operating in a downward flow.

 

[JamesW]

Can any SWG cell be mounted vertically?

No. Some can only be mounted horizontally.

Some use a gas trap design and they have to be mounted horizontally.

The Jandy Pro Series chlorine generating device must be installed outdoors only.

The cell must be installed horizontally with the cord facing upwards to avoid buildup of flammable gases which can result in FIRE OR EXPLOSION.

https://www.jandy.com/-/media/zodiac/global/downloads/h/h0470600.pdf

All Australian models use the gas trap design and they have to be mounted horizontally.

 

[ajw22]

The check valve for solar heating may be required by the solar heat system, not the SWG.

 

[Quinten]

Ok thanks... Only remaining question is regarding the check valve... Can that be omitted or placed below the flow sensor?

 

[mknauss]

Let's ask those with a solar heater if the check valve is necessary.
@mas985 @Dirk

 

[mas985]

The check valve on the return side of the panels is to prevent the solar plumbing from filling backwards when the solar valve is off. This prevents elevated pressure and temperatures in the panels when they are off.

 

[Quinten]

The check valve on the return side of the panels is to prevent the solar plumbing from filling backwards when the solar valve is off. This prevents elevated pressure and temperatures in the panels when they are off.

I guess I'm somewhat unclear on the water flow with the solar... The pipe indicated by yellow is connected with a T from the filter output and the pipe indicated by red is connected when the solar valve is on. The valve on the yellow pipe is manual and I was told to turn that off when the solar is shut off and open to around 75% when the solar is in auto or on. In this case it would seem the panels would be filling backwards when the solar valve is off?

 

[mas985]

It looks like they put the solar valve on the return side rather than the supply side. The problem with doing it that way is you cannot prevent the panels from filling when solar is off. This can also compress any air that is after the VRV so when the pump shuts off, it can rush back out slamming the filter check valve shut. Do you ever hear a loud bang when the pump shuts off (and solar has been off)?

Also, I am not sure why they told you to put the 2-way valve at 75%. That will reduce the pressure in the panels, which may be why they do that, but it could also cause the VRV to open and draw in air. Is there any air coming out of the returns when solar is on?

 

[Quinten]

When the solar turns on there has always been been some air bubbling from the returns for a minute or so, then stops. The solar was put in around 15 years ago. I don't hear anything when the pump shuts off regardless of whether the solar is on or off. Not sure what a VFR is... is that the check valve?

 

[mas985]

VRV stands for vacuum release valve. It is a valve that is installed near the panels so that when the pump turns off, the VRV opens and allows air into the plumbing so the panels can drain.

It is good you don't have any water hammer but the issue with the panels having water in them without any flow is still there. If the panels are on most of the time, maybe it doesn't matter much. The real risk is that with the panels off, the water in the panels will continue to heat up and eventually, it could soften either the panels themselves or the PVC piping allowing for them to deform or even collapse.

 

[Quinten]

OK, thanks... The VRV is at the top corner of the panel layout, it was leaking several years ago and I removed it and didn't see anything unusual (spring loaded flap if I recall), reinstalled it and no issues since. If I were to move the auto valve actuator from the valve with the red pipe to the valve with the yellow pipe, would that be better? I could then place the check valve near where the red pipe enters the ground. Does it matter if the check valve is mounted vertical? I want to add a SWG and can place it in the section where the flow valve is currently using one of the supported vertical mount SWG.

 

[mas985]

If I were to move the auto valve actuator from the valve with the red pipe to the valve with the yellow pipe, would that be better? I could then place the check valve near where the red pipe enters the ground.

That is normally how solar is installed and yes certain check valves (with springs) can work vertically. Specifically, Jandy check valves will work vertically.

The flow control valve on the yellow line is a bit of an oddity too. Not sure why they did that. But are you certain the yellow line is the supply side and red line is the return side?

 

[Quinten]

That is normally how solar is installed and yes certain check valves (with springs) can work vertically. Specifically, Jandy check valves will work vertically.

The flow control valve on the yellow line is a bit of an oddity too. Not sure why they did that. But are you certain the yellow line is the supply side and red line is the return side?

I'm not sure on the supply versus return... I see the output from the filter runs to a "T" right above the yellow line then continues through the automatic valve and depending on whether that is on or off is directed to the solar panels or the return to the pool. If the yellow was the return from the solar would it be routed back into the filter output line from the T above the yellow line?

I really am trying to understand the actual water flow here as it isn't real straight forward to me!