Which joints should I replace to fix selector valve ?

[cadena]

Hi everyone,


I have a Praher Ocean V6 Side Mounted selector valve with 1 1/2" thread connections in my pool. The other day, I used the manual pool cleaner since the pool bed was really dirty and I noticed how all the dirt was coming out of the pool inlet jets back into the pool (which became really cloudy shortly afterwards). This might be caused by the multiport valve (which is really old and the joints might have deteriorated), the sand in the filter or both. I would like to open and replace the joints but I have the following questions:


1.) How do I remove the excess water in the pipes to open the selector valve ? Do I close all valves and let out the water by turning the little knob (see Selector_Valve_Plug picture) under the selector valve ?


2.) Which joints should I replace in the selector valve (see technical guide attached) ? The strange thing from the valve, as you can see in the guide, is that there is no spider gasket so how is the valve able to prevent water from going to other tubes ?


3.) Which glue should I use to stick the spider gasket ?


4.) How can I remove the air that will have entered the selector valve (and pipes) once I finish the task ?


5.) Should I apply vaseline on all joints once they are glued in ? (I've seen a couple videotutorials doing this and would like to know this for sure before doing it).


I would really appreciate your help.

P.S. Can someone confirm me if the connections are threaded and if so, is it because of the hexagon PVC on each tube ?

 

[PoolGate]

I serviced one of these one time and ended up just replacing the entire MPV. You cannot remove that valve to service it even though, yes, the ports are threaded. It was not installed with forethought to allow it to be removed and there are too many slip joints used without unions. But it looks like you have plenty of room to remove the top and replace the gasket. I am not sure what you would use to install the new gasket but would think that the instructions with the gasket would include that information. Also I would not use Vaseline, get a pool grade silicone lubricant instead. I use the below. Shutting off the pump and flow to the MPV should stop water flow unless your valve is below the pool level.

Amazon.com: Super Lube-21030 Synthetic Multi-Purpose Grease, 3 Oz. : Automotive

Amazon.com: Super Lube-21030 Synthetic Multi-Purpose Grease, 3 Oz. : Automotive

www.amazon.com

 

[cadena]

I serviced one of these one time and ended up just replacing the entire MPV. You cannot remove that valve to service it even though, yes, the ports are threaded. It was not installed with forethought to allow it to be removed and there are too many slip joints used without unions. But it looks like you have plenty of room to remove the top and replace the gasket. I am not sure what you would use to install the new gasket but would think that the instructions with the gasket would include that information. Also I would not use Vaseline, get a pool grade silicone lubricant instead. I use the below. Shutting off the pump and flow to the MPV should stop water flow unless your valve is below the pool level.

Amazon.com: Super Lube-21030 Synthetic Multi-Purpose Grease, 3 Oz. : Automotive

Amazon.com: Super Lube-21030 Synthetic Multi-Purpose Grease, 3 Oz. : Automotive

www.amazon.com

Thank you very much for your reply @PoolGate. I have enough space to at least remove the top to replace the gasket. However, should I remove the water from the MPV to change the gasket by using the ventilation screw on the side ? Also once the gasket is installed, how do I remove the air in the MPV ? Also is there a glue you could recommend me ?

 

[PoolGate]

Thank you very much for your reply @PoolGate. I have enough space to at least remove the top to replace the gasket. However, should I remove the water from the MPV to change the gasket by using the ventilation screw on the side ? Also once the gasket is installed, how do I remove the air in the MPV ? Also is there a glue you could recommend me ?

Unless your pool is higher than the valve, water will settle below the valve and you'd simply dry it out. Yes, the side screws will drain the valve body. You do not need to remove any air from the valve once done, just turn it back on.

Try this for glue (or something like it) -> Amazon.com: Hayward SPX0710Z9 Rubber Adhesive Replacement for Hayward Multiport Valves: Garden & Outdoor

 

[cadena]

Unless your pool is higher than the valve, water will settle below the valve and you'd simply dry it out. Yes, the side screws will drain the valve body. You do not need to remove any air from the valve once done, just turn it back on.

Try this for glue (or something like it) -> Amazon.com: Hayward SPX0710Z9 Rubber Adhesive Replacement for Hayward Multiport Valves: Garden & Outdoor

Hi @PoolGate I opened my MPV and from what I saw it was perfectly fine,I have attached the pictures I made this morning of the interior. The spider gasket and O-Ring seem completely fine. The handle is what's more difficult to turn around and I'm tempted to use a 3-in-1 multiuse oil to lubricate the handle (unless you advise me otherwise). However, I thought the MPV joints were ruptured because whenever I move the handle to circulation, the manometer goes up to almost 0.7 bar, which makes no sense at all since water should not go into the filter in that mode

 

[PoolGate]

I would lubricate the gasket and spring with a good synthetic lube like Magic lube. I don't have a MPV but I have used them. When they are working correctly they are not hard to change between settings.

 

[cadena]

I would lubricate the gasket and spring with a good synthetic lube like Magic lube. I don't have a MPV but I have used them. When they are working correctly they are not hard to change between settings.

As always, thank you very much for your reply @PoolGate but would lubrication solve the issue with the filter manometer rising up to 0.7 bar when the MPV is in circulation ? Should I, perhaps, open a different thread for that issue ?

 

[PoolGate]

As always, thank you very much for your reply @PoolGate but would lubrication solve the issue with the filter manometer rising up to 0.7 bar when the MPV is in circulation ? Should I, perhaps, open a different thread for that issue ?

This thread should be good with that but I am not sure what you are measuring with the manometer? Is that your water pressure gauge? @mknauss any ideas?

 

[mknauss]

I suspect the 0.7 is bar. So 10 psi.

I assume you meant Re-circulation. The Pressure should go down in that position.

 

[cadena]

Hi @mknauss yes I mean Re-circulation so the pressure of the water pressure gauge in my filter should go down to 0. But I have opened the MPV this morning and the joints all seem to be fine as you can see in the picture so I don't understand then what could be causing the pressure to go up in the gauge.

 

[mknauss]

MPV Valves - Further Reading

www.troublefreepool.com

Here is an article on MPV's. I do not have any direct experience with them.

 

[cadena]

MPV Valves - Further Reading

www.troublefreepool.com

Here is an article on MPV's. I do not have any direct experience with them.

Hi thank you for the link @mknauss but the tutorial does not cover the situation were water leaks to the filter when in Recirculate mode. It doesn't make sense since, as you can see in the pictures above, the valve (joints, spring, etc.) is perfectly fine. Is there perhaps an MPV expert or another member who might know the cause of this problem and how it can be solved ?

 

[PoolGate]

Have you tried letting pressure out of your filter while in recirculation mode to see if what you are seeing isn't just residual pressure? As long as everything works as expected in filter mode, I don't think you have an issue. All of the other modes are meant for maintenance and not as a long-term setting.

 

[cadena]

Have you tried letting pressure out of your filter while in recirculation mode to see if what you are seeing isn't just residual pressure? As long as everything works as expected in filter mode, I don't think you have an issue. All of the other modes are meant for maintenance and not as a long-term setting.

Hi @PoolGate, following your advise, I have tried turning the screw on the top of the filter to let out any air in the filter. I turned the screw until water began making its way through the screw. I waited something like 10 minutes but the pressure gauge didn't go down at all. In that case it has to be something else... but the MPV seems fine which makes no sense at all.

 

[cadena]

The problem I also have is that I have used Flocc in the past and I need to be sure that recirculation mode has not let some of the Flocc into the filter. Right now when I use my manual vacuum cleaner I can see a jet stream of dirt coming out from the pool inlet jets and I don't know if the issue is the MPV, the filter or both things.

 

[PoolGate]

It is possible the MVP has warped and even though the spider gasket is new, it still doesn't 100% seal between water passageways. I am not sure did you mention how old the valve was? In my opinion, sand and DE filters along with their associated MPVs are obsolete relics of the past. If you end up replacing it, do yourself a favor and replace the filter with a cartridge style.