Plumbing Considerations during SWCG install

[Steelkilt]

I will be adding an in-line SWCG, flow switch, and sacrificial anode to convert our existing pool.
I'm confused as to the existing check valve on the plumbing right before the heat pump. Any ideas as to why this is located here? The documentation I pulled from the heater doesn't show any configurations of pool/spa/heaters that would necessitate a check valve in this position. Maybe at some point there was a bypass loop or isolation valves?
I would certainly welcome any feedback on my proposed install/diagram.
Existing System: Pump > Filter > Check Valve > Heat Pump > Return
Proposed: Pump > Filter > Sacrificial Anode > Heat Pump > Check Valve > SWCG > Return

 

[pjt]

While you're replumbing your system, add a bypass to your heat pump. You don't need a sacrificial anode. You also don't need a check valve before the heat pump (put it after the heat pump as part of the bypass).

 

[Steelkilt]

While you're replumbing your system, add a bypass to your heat pump. You don't need a sacrificial anode. You also don't need a check valve before the heat pump (put it after the heat pump as part of the bypass).

No anode eh? Reading some things that say it doesn't hurt, and I figured while I've got the plumbing disconnected the timing would be OK.
I will plan to install a bypass on the filter. Is there a preference one way or the other in doing so with a 3-way diverter vs. ball valve and tee approach?

 

[pjt]

The anode won't do anything for you. But, it's your pool and if you think it adds value, go for it. There are many TFP threads on anodes.

You want to add a bypass to your heat pump, not your filter. A quality 3-way diverter and a check valve is all you need in addition to your PVC pipes and fittings.

 

[Steelkilt]

The anode won't do anything for you. But, it's your pool and if you think it adds value, go for it. There are many TFP threads on anodes.

You want to add a bypass to your heat pump, not your filter. A quality 3-way diverter and a check valve is all you need in addition to your PVC pipes and fittings.

Much thanks! Correct on the heater not filter, got my words crossed, doh!

 

[Steelkilt]

I will take the advice and install a 3 way diverter valve prior to the heater and check valve after to create the bypass.
how do I handle the existing unions and reducers to and from the heater? I’m planning on redoing all exposed plumbing between filter and return to fit everything. Are these unions typically a threaded connection to the 2” heater inlet/outlets?

 

[Steelkilt]

Well, today I learned that not all 2” unions have the same thread size.
I purchased 2 new unions with the intent of glueing on half to the lengths of new pipe and matching the existing already glued half on the heater. Threads don’t match so it’s off to scour the internet for the exact match. Fingers crossed! No opening the pool this weekend, doh!

 

[Steelkilt]

Hi folks!
I’m back and my system is all dry fitted - I was hoping the community may provide some feedback prior to glue up? As always thank you TFP !

 

[Find Me Floating]

Hi folks!
I’m back and my system is all dry fitted - I was hoping the community may provide some feedback prior to glue up? As always thank you TFP !

Be advised---"Dry Fitting" can get you in trouble with any of your critical dimensions. You cannot fully seat the pipe in the fittings when dry (without glue). Therefore, if you are measuring off that things will change quite a bit when you go for the final glueing.

You may know and understand this. But others may not. I almost screwed the pooch on my install before I realized.

 

[Steelkilt]

Be advised---"Dry Fitting" can get you in trouble with any of your critical dimensions. You cannot fully seat the pipe in the fittings when dry (without glue). Therefore, if you are measuring off that things will change quite a bit when you go for the final glueing.

You may know and understand this. But others may not. I almost screwed the pooch on my install before I realized.

Absolutely, great reminder. I did take this into consideration so as to not find myself short on the critical lengths.