Brass hydrostatic relief valve 1963 chlorine pool replacement?

[CMH-CVG]

While resurfacing the pool, following sandblasting a number of brass fittings became visible.
The deep end drain grate, a hydrostatic relief valve, and an attachment for buoys the separate the deep end are all made of brass.

The hydrostatic relief valve lost its spring (user mistake during draining or it has been without a spring for years, I'm unable to discern). The pool has had no leaking in the 3 years I've own it. (35,000 gallons, chlorine)

The pool resurfacing company wants to replace the old relief valve system with a whole PVC setup, including cutting into the cement/shell, replacing the old setup, and installing a PVC L-tube and PVC valve.

A web search found several brass hydrostatic relief valves that can be similar to what exists.

Seeking advice to: a) replace the entire setup, cutting and installing a new L-shape and PVC valve
or b) replacing the current valve with another brass valve, or just repairing the spring.

Likely option to follow even though is more intrusive:
The pool company prefers to replace it with a new PVC hydrostatic setup, cut the cement, install a L-shape and PVC valve that can be closed off while filled and open after draining.
I suppose this will have a better warranty in case if future leaks vs just replacing the the missing spring, or a new brass valve.

Advice to take the intrusive approach, which will be replasterred and made look even, and avoid future leaks,
or dont cut into the shell and just repair the existing valve.
(unfortunately while I did not have any leaks in the 3 years with the pool, I dont know if the spring or the valve was damaged while draining and I will have leaks afterwards....)

see images from amazon on potential brass hydrostatic valves

 

[Texas Splash]

Your situation is a bit unique, and the clock is ticking, so I’m going to send-up the bat signal to a few experts in the field: @1poolman1 , @AQUA~HOLICS , @MAPR-Austin, @Pool Clown

 

[AQUA~HOLICS]

I have no personal experience with this type of value from the new construction side of the industry.
My advice would be to keep as much metal exposure to the water chemicals to a minimum if possible. The swimming pool industry has made this move years ago and for good reasons.
Even though the replacement option is intrusive, if done correctly, this may be the best case scenario for your specific situation.

 

[CMH-CVG]

I have no personal experience with this type of value from the new construction side of the industry.
My advice would be to keep as much metal exposure to the water chemicals to a minimum if possible. The swimming pool industry has made this move years ago and for good reasons.
Even though the replacement option is intrusive, if done correctly, this may be the best case scenario for your specific situation.

Thank you. Most likely For warranty on the resurfacing, and no leaks, I’ll have to proceed with the intrusive approach of cutting down the cement/shell and using PVC.
I did tell the PB that I want to discuss options and reach the best decision (pros and cons)
Will update how it turns out

 

[JamesW]

With your elevation, do you need a hydrostat?

 

[MAPR-Austin]

I personally wouldn't cut into the shell. I would just get the old hydrostat out and put a new on in it's place - there are plenty of PVC hydrostats out there that will fit the bill just fine.

 

[CMH-CVG]

I personally wouldn't cut into the shell. I would just get the old hydrostat out and put a new on in it's place - there are plenty of PVC hydrostats out there that will fit the bill just fine.

It is a brass pipe covered by cement with no visible thread or attachment.

Before cutting will see if opening the cement around the tube discovers a threaded connection.

The challenge is warranty after the new plaster is placed, if I have leaks for a system they did not recommend.

 

[MAPR-Austin]

It is a brass pipe covered by cement with no visible thread or attachment.

Before cutting will see if opening the cement around the tube discovers a threaded connection.

The challenge is warranty after the new plaster is placed, if I have leaks for a system they did not recommend.

Maybe split the difference, see what they would charge to simply install a new hydrostat without going through cutting up the pool floor. Worst case would be they have to do a bit of prep in the bottom of the main drain pot and install a threaded fitting for the hydrostat to go into. A bit of hydraulic cement should seal things up pretty well.

 

[CMH-CVG]

image of the 1963 hydrostatic valve pulled out of the pool after removing the cement? covering the threads. PC was unable to unscrew the valve (rusted) and a new PVC tube/valve was installed.
Thanks for the guidance provided