Welcome to Plbg.com
Thank you to all the plumbing professionals who offer their advice and expertise

Over 698,000 strictly plumbing related posts

Plumbing education, information, advice, help and suggestions are provided by some of the most experienced plumbers who wish to "give back" to society. Since 1996 we have been the best online (strictly) PLUMBING advice site. If you have questions about plumbing, toilets, sinks, faucets, drains, sewers, water filters, venting, water heating, showers, pumps, and other strictly PLUMBING related issues then you've come to the right place. Please refrain from asking or discussing legal questions, or pricing, or where to purchase products, or any business issues, or for contractor referrals, or any other questions or issues not specifically related to plumbing. Keep all posts positive and absolutely no advertising. Our site is completely free, without ads or pop-ups and we don't tract you. We absolutely do not sell your personal information. We are made possible by:  

Post New
Search
Log In
How to Show Images
Newest Subjects
 Making multiple PVC solvent welded joints simultaneously
Author: sum (FL)

I have a bit of a situation with my pool plumbing I am trying to resolve. Basically, my pump is sitting too high, and the 2" manifold feeding the suction side of the pump is sitting too low. As you can see in the image below, the manifold on the left is a good 12"+ lower, requiring the piping to go through two 90 elbows for this offset.



I would like to raise the manifold, and lower the pump to even them up.

In order to raise the manifold, everything needs to be raised. The manifold consists of four three way valves, connected together before and after with all adjoining fittings, there is not a section of exposed pipe I can isolate them so I can work on them in pieces. The entire section in red needs to be raised as one piece.



Now to raise the whole thing, I need to make a cut all the way across the bottom (see the red line), cutting all four pipes. Then I can add four couplings, short section of pipe, four more couplings.



I have looked at this multiple times and it seems to me that the final connections will be made by doing FOUR solvent welded joints at the same time, with no opportunity to twist the pipes or couplings to spread/even the cement. How likely will this be successful? Do you see another way I can do it piece meal without getting all new valves and fittings?

Post Reply

 Re: Making multiple PVC solvent welded joints simultaneously
Author: bernabeu (SC)

use 4 PVC solvent weld unions instead of 4 of the couplings


requires PRECISE measurement(s) and cuts


eg. plumbing/pipefitting

==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638



Edited 1 times.

Post Reply

 Re: Making multiple PVC solvent welded joints simultaneously
Author: sum (FL)

I did some measurements and I don't think I can use four unions in a row across like that.

The 2" PVC unions are very large (diameter wise), that if I have them next to each other two of them will not fit next to each other side by side. If they do fit there will be no room to even fit a plier over one to loosen or tighten.

If I use 4 unions I have to position them so that the first one is lower the second one higher the third one lower the forth one higher. May be two outer unions and two inner solvent weld couplings? I don't know.

Post Reply

 Re: Making multiple PVC solvent welded joints simultaneously
Author: Sauktim (WI)

Do they make compression couplings you could use and stager them on the verticals or put some before and after the valves?

Post Reply

 Re: Making multiple PVC solvent welded joints simultaneously
Author: steve (CA)

Sum, what about rubber hose and clamps?

Post Reply

 Re: Making multiple PVC solvent welded joints simultaneously
Author: bernabeu (SC)

so ..... stagger them .... hi-lo-hi-lo

==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

Post Reply

 Re: Making multiple PVC solvent welded joints simultaneously
Author: sum (FL)

steve what do you mean rubber hoses and clamps? You mean something like Fernco rubber couplings they use for drains?

Post Reply

 Re: Making multiple PVC solvent welded joints simultaneously
Author: Don411 (IN)

I have to ask what the point of raising the manifold is....is it just to eliminate the 2 elbows going into the pump strainer? Is there a performance or flow issue that you're trying to fix?

Assuming there is a reason to do this, I agree that glue joints will be difficult....there is a lot of risk in getting 4 unions to come out at the exact height on both sides of the connections.

I would consider using Fernco banded couplings rather than glue...that would give you added flexibility for repair if you need to change one of those port valves. Not sure if there would be issues with pool chlorine affecting the rubber couplings?

Also, looking at the second picture, that brown pipe looks like it's directly above the right-most port valve. if you just raise those indicated in the third pic, that right side valve will be directly under that brown pipe and will be difficult to operate. Don't forget that you need to leave that coupler between the manifold and the strainer so that you can disconnect the pump for servicing.

Post Reply

 Re: Making multiple PVC solvent welded joints simultaneously
Author: sum (FL)

There are a lot of reasons to raise the manifold.

The main reason is the manifold in it's present elevation is too low. When I first bought the property two years ago, the pump and the manifold were at the same elevation. with a 2" closed nipple connecting the two.

The problem was, the pump was half buried in mud, most of the manifold was also invisible. There were so much leaves that fell into that area from overhanging trees, that the bottom layer of leaves were turning into mulch. That closed nipple was leaking and there was no way to fix the leak because I could not tighten the nipple. After a few days of cleaning out all the leaves, excavating the wet mulch and mud around the pipes and pump, I found the pump connections were leaking at the suction side, the outlet side, and the inlet to the filter. All the leaking water was seeping into the ground, and invited all kinds of roots from nearby plants to wrap around some of the pipes. I was able to get see the entire manifold like this after turning off the pump and allowing everything to dry.



The solution is clear to me, I need to put both the pump and filter on a concrete pad to raise them off the ground. But the ground is so soaked and mulchy from years of leaks and leaves and it's impossible to clean it up without taking everything apart and out of the way.

I had to fix the leak between the manifold and the pump. There is no piping between them except the close nipple. So the only thing I could do at the time is to excavate below the pump, to dig out enough of a hole, disconnected the electric wiring, so I can spin the pump in place to unthread from the manifold.

I then put the pump on a few concrete blocks and slid a concrete step stone under the filter. But this caused the manifold to be much lower. So I piped in two 90 elbows and a union in between to allow disconnection to service the pump. Turned out the union is not needed because I found out there is a fitting for pump inlet/outlet, that is a compression male connection and a union all in one fitting, and is designed to withstand the higher temperature that may happen on a pump. My intention is to switch to that and get rid of the bigger bulky union.

But putting the pump on concrete blocks is not a permanent solution. The pump cannot be secured like I can if I had a larger footprint concrete pad I could install concrete anchors to prevent the pump from excessive movement from the vibration and from the service tech opening and closing the pump lid to clean.

I am planning to install a concrete pad under both the pump and the filter. Once that's done, I will raise the manifold to align the outlet and inlet elevations so it will be a straight shot and the manifold will no longer be hugging the ground, making that area difficult to clean and kept tidy.

I am not worried about that higher brown pipe. That pipe has no reason to be in the way and can be easily re-configured to make way.

The individual valves do not need to be disconnected to be serviced. Those valves have internal replacement parts and the top lid can be removed for access. If an entire valve needs replacement, then there is no way to do it anyway because all these valves are interconnected with back to back fittings unless I start to mess with fitting saver bits.

Another reason I want to raise the manifold, such as I am getting a new spa heater and it is taller and I would like to run the loop into and out of the heater without too many offset elbows, and other reasons too tedious to get into without writing a novel,

I am also worried about the painted pipes where I plan to make the cuts. If I aggressively sand and scrap them off if that will still be making a good solvent weld joints.

I am not sure about using rubber couplings on a pressure line.

Post Reply

 Re: Making multiple PVC solvent welded joints simultaneously
Author: Don411 (IN)

Makes sense. You are going to love the heater! We had a 300k BTU natural gas heater on our pool in NY and it was fantastic! We just started looking at a pool for this house and they have electric heat pump pool heaters! I haven't done the research yet but our only utility here is electric (and cable).

BTW, those are suction lines, not pressure lines going into that manifold.

Post Reply

 Re: Making multiple PVC solvent welded joints simultaneously
Author: Sauktim (WI)

This is where I figured compression couplings might help. Appear to have a thinner profile and rated well over 100 psi. And would give you enough play to level things out. Saw some on the Home Dumbo site.

Post Reply

 Re: Making multiple PVC solvent welded joints simultaneously
Author: sum (FL)

you are right, suction lines are not technically pressure lines. However, I treat them like pressure lines, may be even more so because I want the suction side to be as trouble free as possible. To me, if the positive pressure side leaks, I can see it, either beading or misting water. If the suction side leaks, I will never see it, it will not form a bead of water or dripping. The only possible clue is may be bubbles inside the pump. So I want to do it the most "bullet proof" way, if that's possible.

The other thing is, this is a one shot deal. I cannot try something and redo it if it fails. There is not enough pipes to cut back and redo.

Post Reply

 Re: Making multiple PVC solvent welded joints simultaneously
Author: sum (FL)

I will look into the compression couplings.

I think I have looked at them before I am not sure the 2" compression coupling nuts are significantly smaller in OD then a 2" union. I will check again, The thing about compression couplings is then I am dealing with 8 nuts to tighten.

Post Reply

 Re: Making multiple PVC solvent welded joints simultaneously
Author: Don411 (IN)

The slightest suction leak will show you bubbles in the skimmer basket before the pump, and it kills the efficiency of the whole circulation system. Suction can be harder to seal than pressure, but theoretically if a coupler will hold pressure it should hold vacuum.

Post Reply

 Re: Making multiple PVC solvent welded joints simultaneously
Author: bernabeu (SC)

in practice NO


suction creates 'shrinkage' of rubber gasket 'bearing surfaces'

as opposed to pressure creating 'expansion'

==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

Post Reply





Please note:
  • Inappropriate messages or blatant advertising will be deleted. We cannot be held responsible for bad or inadequate advice.
  • Plbg.com has no control over external content that may be linked to from messages posted here. Please follow external links with caution.
  • Plbg.com is strictly for the exchange of plumbing related advice and NOT to ask about pricing/costs, nor where to find a product (try Google), nor how to operate or promote a business, nor for ethics (law) and the like questions.
  • Plbg.com is also not a place to ask radiant heating (try HeatingHelp.com), electrical or even general construction type questions. We are exclusively for plumbing questions.

Search for plumbing parts on our sponsor's site:




Special thanks to our sponsor:
PlumbingSupply.com


Copyright© 2024 Plbg.com. All Rights Reserved.