Why did my filter fittings crack

[Braydon]

Hey all, i am trying to help my father inlaw figure out why his multiport diverter broke twice(broke, we replaced andthen new one broke), a fitting on the the return side of it cracked. And the sand filter drain plug cracked. I asume its due to high pressure but when we replaced broken parts and turned it on, the psi was hanging around 15. Just trying to wrap my head around this as we dont want to put on this 3rd multiport valve and have it break again.

Any thoughts welcome or any ideas on how to narrow down where a blockage could be if thats the issue

Braydon

 

[Bperry]

Hey all, i am trying to help my father inlaw figure out why his multiport diverter broke twice(broke, we replaced andthen new one broke), a fitting on the the return side of it cracked. And the sand filter drain plug cracked. I asume its due to high pressure but when we replaced broken parts and turned it on, the psi was hanging around 15. Just trying to wrap my head around this as we dont want to put on this 3rd multiport valve and have it break again.

Any thoughts welcome or any ideas on how to narrow down where a blockage could be if thats the issue

Braydon

The fittings usually only break when they are tightened too much. Maybe an example picture of what actually broke might help.

 

[Braydon]

I agree but the fact that the fitting, drain plug and multiport all broke makes me belive its a larger issue. Ill try to get photos

 

[Braydon]

We took apart the multiport valve to show where it broke

 

[Braydon]

Also found this, its like a filter just before the salt cell. Its all warped like it heated up or something. Just another odd observation. Not sure if it relates to the filter cracking issues but def doesnt seem good

 

[Bperry]

Also found this, its like a filter just before the salt cell. Its all warped like it heated up or something. Just another odd observation. Not sure if it relates to the filter cracking issues but def doesnt seem good

If the heater ever turned on while the pump was off and didn’t have a flow or pressure switch, that could cause some extra heat like that. Tough to say on the other parts doesn’t seem like water pressure could break the handle like that, but I don’t know for sure.

 

[Pool_Medic]

Unions or valves break from being over tightened, ppl over tighten them perhaps due to misalignment from first install, requiring additional force to stop leaks. Lots of lube on o rings can solve a lot of leak issues.

 

[1poolman1]

Has any of the equipment ever not been drained and then frozen? Not uncommon in Michigan. That would account for all three items that are broken.

 

[sktn77a]

That filter drain plug picture is a classic "too tight" failure (ask me how I know)! Do not put any silicone/teflon lube on the threads, only on the rubber bottom seal (try not to get ANY on the threads) and tighten it just enough to prevent leaking. Same with the union. No idea what happened with the MPV key seal diverter breaking(?)

 

[Bperry]

That filter drain plug picture is a classic "too tight" failure (ask me how I know)! Do not put any silicone/teflon lube on the threads, only on the rubber bottom seal (try not to get ANY on the threads) and tighten it just enough to prevent leaking. Same with the union. No idea what happened with the MPV key seal diverter breaking(?)

Yea, I wonder if the MPV valve was not unlocked before turning or not.

 

[Braydon]

Thanks for all the input. What do you mean unlocked? I know his original MPV worked well for years, broke, replaced and then 2 weeks later new one broke the same way. I get that we can say over tightening is the most common culprit for those fittings and i understand. Its just hard to belive when all 3 parts broke at same time and it doesnt explain the mpv issue. Just soo odd.

 

[Braydon]

Ill ask about the possible freezing idea. Im not familar with his winter closing process

 

[Braydon]

Are you able to expand on how freezing can account for the new mpv breaking? Not saying i dont belive that could be it, i just want to understand hypothesis and the thought process on how it could occur.

Thanks for the input

 

[1poolman1]

Are you able to expand on how freezing can account for the new mpv breaking? Not saying i dont belive that could be it, i just want to understand hypothesis and the thought process on how it could occur.

Thanks for the input

Just a guess from 2000 miles away. The other damage looks similar to freeze damage I've seen locally (yes, it does freeze in Sacramento at times).
The drain plug damage could have been from being overtightened but ice will cause that, also. The crack at the union would have been on the collar if it were overtightened. Can't overtighten the MPV. Pressing down on the handle unlocks the valve from its position so it seems the damage happened internally. If the valve were frozen (diverter stuck in one position by ice) and someone tried to force it to move the stem could break like what is seen. The plastic would have been very brittle due to cold conditions. If it is new, you should try to get it replaced under a warranty.

 

[Braydon]

Yea he is going to try to return the broken one. The freezing idea make sense but its been 90 degrees lately. Cant imagine freezing was at play with the new one as it just broke this month

 

[Bperry]

Thanks for all the input. What do you mean unlocked? I know his original MPV worked well for years, broke, replaced and then 2 weeks later new one broke the same way. I get that we can say over tightening is the most common culprit for those fittings and i understand. Its just hard to belive when all 3 parts broke at same time and it doesnt explain the mpv issue. Just soo odd.

Before you try and move the MPV lever you need to push it downward, and then it can move freely. Other valves may have a different motion you need to do to move them, but mine requires you to push it downward. It’s a fairly obvious “notch” that the handle has to pop over but I thought I’d mention it in case your FIL didn’t realize it.

 

[Braydon]

Yea he knows how to use the MPV. The strange part is that it broke on its own. Walked out one morning and these things were broken. Which is why i feel something created a pressure spike and caused this. But its still a mystery.

 

[Poolbreh]

Is your swg on the line side? If the flow switch gets stuck closed and there is no flow, it will build up hydrogen gas in the lines which could cause the cracks and create a lot of heat in the cell which could cause the screen piece to warp.

 

[JamesW]

These marks indicate a pair of pliers were used, which is too much torque.

 

[Darin]

That crack is where the gasket is inside. You over tightened it. Only hand tight. Cheap lesson learned.
JamesW is correct.