View Full Version : Check Valve question

06-14-2011, 09:53 PM
I purchased this 2" swing flapper type check valve with a 1/2 lb. spring, will the water have enough force to open the spring or will it be too restrictive to water flow?

If it is can I just bend or remove the spring too lessen tension? Also, does it matter if the check valve is placed in a horizontal or vertical position. I would like to put it horizontally and underground. Does it need to be accessible as well?

I am using a Sequence 4200 pump, does it matter which comes first after the pump, the check valve or the ball valve? I think it would go in this order: Pump, Check Valve, Ball Valve, Tank.

If I am wrong please set me straight. Thnxs folks.

06-14-2011, 10:07 PM
The Sequence pump should be plenty strong enough to operate the valve. The valve has an arrow on it showing the direction of water flow. Be sure to face it in the right direction!

The check valve should go between the pond and the pump. You should have enough pipe between the valve and pump so there will be enough water left in the pipe to re-prime the pump when it shuts off. The purpose of the check valve is to hold water in the pipe when the power goes out and the pump is above water level. If the pump were a flooded suction, you wouldn't need the check valve.

I usually try to leave at least 10' between the check valve and pump.

Yes, it can be buried. Once installed, you can't service this type of valve. You should also have a mech filter before the valve so trash does not go through the valve causing the flapper to stay open.

In order from the pond:

Mech filter, check valve, at least 10' of pipe, ball valve, pump, filtration.

06-14-2011, 10:09 PM
I prefer a swing check valve, which has a loose flapper--and not a spring check valve. I feel these do put unnecessary resistance on a pump.

06-14-2011, 10:12 PM
Lisa, we posted at the same time.

The purpose of the check valve is to hold water in the pipe BEFORE the pump when the pump is above water level. In the event the power goes off, all the water is drained from the pipe so when the power comes back on, the pump has no water to prime it.

The check valve goes before the suction side of the pump so there's always water in the pipe to prime it.

06-14-2011, 10:32 PM
With a 2" check valve, I would do some things: When you bury it, leave it reasonably easily accessible, like a plumbing access port from Lowes or HD that is longer than the valve. Then, DO NOT GLUE IT. Use 2 2" Fernco couplings to attach it. I've had 2" valves get stuck before, because shit happens. You can service the valve then, simply by loosening the Fernco clamps and removing it, to dislodge whatever may get caught in there. It's a little more to it, but it looks professional with the covered access box, and it can save you sawing it out after you dig it up, probably in winter, in cold, wet, uncomfortable freaking mud.

Can you tell I find this situation familiar? Experience can be a harsh teacher, try to learn vicariously through me. And, make sure, if you're putting it horizontally, that you put the right end up, if not and the spring fails for any reason, it won't work.

06-14-2011, 10:35 PM
Oh, and it work better if it is below pond water level. I don't even think you need the 10' of pipe if the check valve is below the pond water level.

06-14-2011, 10:37 PM
Good point, Will. I've had to cut out 3 check valves on the mud pond last year because it isn't a swing valve and there's no way to put a filter on it. Ferco's are life savers.

I'm surprised you could find a 2" with a flapper. I couldn't even buy them at the plumbing supply house. The smallest swing valve they have is 4".

06-14-2011, 10:50 PM
See I knew i was asking the right people I would have made a big boo boo tomorrow since I plan on gluing pvc n pump togethter. Sandy I also noticed you said the ball valve goes before the pump, whats the purpose for that wouldnt it go after the pump but before the filtration to be less restrictive to the pump. Please explain I know I am wrong in thinking this way I just want to do it right the first time.

I plan on using a retro drain so what could i use for a mech filter, something like a milk crate with filters on the outside or a laundry basket type thing. I recall reading something like that in a thread somewhere. What do you ladies suggest.... Thnxs Lisa n Sandy

06-14-2011, 11:14 PM
Will, The check valve will be underwater now that I found out it goes before the pump. I will be coming up from the bottom of pond with some type of retro drain, with the check valve still under water then over the top of pond, I have about 5-6' of pvc between check valve and pump to put the ball valve.

So since the check valve will be underwater do I still use the Fernco couplers or can I just slip pvc to check valve since it will be underwater, easier to remove should clogging occur maybe?

Do you folks recommend a particular retro drain that would work well in this application?

And what to use for a mech filter at retro drain?

Sandy I bought the 2" check valve online from flexpvc.com Thnxs again everyone!

06-14-2011, 11:28 PM
If your pump was below the water's surface, a flooded suction where you will have water in the pipe even when the power is out, you wouldn't need a check valve. The only reason to use it is to keep water in the line when the power goes off. As the power stops, the pump sucks the water out of the pipe and the remaining water goes back to the pond so the pipe is empty. When the power comes back on, the pump is sucking air and won't restart.

If you put the valve AFTER the pump, on the output side, there is still no water in the pipe to re-prime the pump.

As far as I know, you can't use a check valve in the vertical position.

You could use a leaf basket for an inline pump as a pre-filter for the check valve. They're about $40.

06-14-2011, 11:43 PM
Sandy, I didn't see Y2K specify that his pump was above or below water line....and that certainly does make a difference. I assumed the pump would be below pond line--which of course is a silly assumption. I should have asked the question indeed.

To clarify, my check valve is immediately after my pump because my filter is raised on blocks way above pond level (but my pump is below pond level). In my case, it prevents dirty filter water from sliding back into my system in the case of a power outage.

06-15-2011, 12:14 AM
Sandy, my fault I should have given a more specific explanation of my setup...well here it is in pics. Let me know what you folks think I should go from here. Thnxs :dunno:

06-15-2011, 12:17 AM
Lisa my stock tank is also raised on blocks above water level to the left of 2nd pic.....I am so confused. Help!

06-15-2011, 01:10 AM
OK, man. New pond, so why retro BD? Why not real BD? With a retro, you still need to pierce the liner below water level. You've got some right ideas, though. Here's what I'd change: 1. remove all that 2" input pipe. You need to use a reducer to enter the pump, but everything else from the BD should be 4", no checkvalve, as your motor will be flooded. That means you never have to turn it off, though, just open the leaf basket slowly, dump, replace. On the pump feed line (4" line), never get above pond level with that big pipe. Just set the BD in a bag of concrete, level and plumb right through the bottom of that liner, great instruction is on the site. 2. Put your 2" checkvalve after the pump, but be sure to orient it correctly and use the Ferncos, just in case. You can use it vertically, just make certain of how it is oriented. 3. trade out that sharp 2" elbow after the pump, you never want to use those type of elbows. Instead, try to find either 2" flex PVC or use conduit bends, they're a lot gentler, reduce your dynamic head.

From there, you can have a twin set of s&g filters in parallel, both exiting toi your bio. That could be both s&g's going into one shower, or a moving bed, any good biofilter. Freom there to TPRs, or whatever you've got planned.

06-15-2011, 01:29 AM
Will, So I cant come over the top of liner like i have it right now? I dont like the idea of cutting into liner from anywhere but I will take your suggestion and check out the instructions on this site. So youre saying that retros is not the way to go huh...I really dont feel like digging anymore especially in this heat LOL

Let me get back with you as it is getting late here....Thnxs alot.

06-15-2011, 01:50 AM
Here too. With a new pond, why not put in a real BD? It really is easy, doesn't take much more digging (1.5" X 1.5', then a narrow trench for your 4" BD line), a flooded pump is so much better. It won't have water supply head loss. Put an aerated BD in in it, and you're set. You can make these by using conduit parts if needed.

06-15-2011, 06:31 AM
It's not that hard to put a real BD in a liner. People do it all the time. Any time you have some thing in the pond like pipes the fish can scratch them selves on it and get wounds then infections. Your much better off with a real BD.

06-15-2011, 08:45 AM
I tried doing a retro drain on my old pond (that had zero filtration when it was built 20 years before by the previous owner of the house) and go up and over the wall, but I could not get proper suction because I'd get an air pocket at the point of the wall hump because my pump was too far down on the other side of the wall in a pit--exactly like yours. You will probably suffer the same issue. I then had to dig down beside the liner and pierce it and put a bulkhead through the liner. Worked like a charm.

In your case, I'd put a real BD in though. It does not make any sense not to. And you should not go with anything less than 3" pipe for that. Go to the Marketplace forum and look at WeWilly's postings for aerated bottom drains--you will not beat his prices.

06-15-2011, 09:29 AM
Lisa, when you have a line going over the top like that, drill a very small hole at the top bend to let the air escape.

I learned a few things on this thread. I didn't know you could put a check value vertically. I also never thought about using them to stop water from flowing from one filter to another. I've always used expensive knife valves. I won't be wasting that money anymore. THANKS!

06-15-2011, 11:19 AM
Here is a link you will love. It explains exactly how to install a bottom drain. I have put in at least 10 of them and never ever had a single problem out of any of them.


06-15-2011, 11:26 AM
I guess its back to the drawing board and back to more digging a trench for that BD now. So if I'm understanding it right, dig a trench from the lowest point in pond where the pipe was going to pull the water up, go across the bottom towards the side of pond and come up along side the pump house on the inlet side. Right.

I will have to find threads on this BD installation and possible pictures to help me figure this out. I am just a novice at all this so just be patient with me and sometimes spoon feed alittle at a time okay. I want to keep it as simple as possible with pond working right.

I am a visual creature so pics, videos etc would help alot. Thnxs to all the Pond Forum crew for helping out. Stay tuned....

06-15-2011, 11:30 AM
Sandy, are you saying that drilling a small hole at the bend of the pipe at its highest point will resolve the air pocket problem? Wouldnt water come out of the small hole?

06-15-2011, 12:15 PM
Dejesus, you've got the idea down about the bottom drain. That link that Cindy gave you at the end of the last page is a great one, very visual. The difference will be that you'll be trenching up the wall of the pond, too. Something else to keep in mind: When you do water changes, your water level will drop. Ideally, your pipe to your pump should be below water level a good bit, just to avoid any priming issues if the water level drops, like water changes, etc. Not really a problem, though, if you never turn your pump off, unless a power failure occurs.

BTW, at the end of my post last night, I was really, really tired. I don't know what the hell I was talking about with the conduit pieces, I think two ideas somehow merged in my exhausted mind.

06-15-2011, 12:17 PM
Cindy you read my mind, thanks for that helpful link.

06-15-2011, 12:29 PM
Will, I think we were both tired at that point....I checked out the link Cindy sent me and yes it was very helpful. I am going to check out marketplace and WeWilly to see how much more investment I have to put into this pond build. I plan to keep a positive attitude and not get too frustrated throughout the building and growing pains.

You folks guys n gals need to keep me motivated on this or I may never finish this pond or worse give up. Thnxs to all really!

06-15-2011, 01:33 PM
Never give up! Mission must be accomplished, eh?

You could save a bit by going with Bill's (WeWilly) standard cheapie 4" BD, then also get a Matala air diffuser from him, and attach it to the top of your BD. You might ask him if he's got one with the center support for the BD anti vortex dome, and you could run your air hose right down that support and drill a hole through the bottom of the BD, then run your airline right through the concrete under the drain and up through the trench for the 4" pipe. That way, you wouldn't have to worry with an airline floating around the pond. I wish I'd had that idea before setting my BD in, I didn't even know about aerated BDs at that point.

06-15-2011, 03:14 PM
Depending on where the lowest part of your pond is, that's where you would put the BD. However, the BD usually only pulls from about 8' so you'd want to try to center it as best you can so that it will cover the bottom. You also should slope the sides towards the drain.

Yep, who said keeping koi was easy or cheap? LOL

Just think, if you're like Cindy and I, you'll be digging a bigger, better version by next year!

06-15-2011, 07:19 PM
Sandy, not a whole lot of folks are like you and Cindy. I'm working on it, though.

06-15-2011, 08:05 PM
Between Cindy and I, I think we've built enough ponds just for ourselves to give everyone here a pond. LOL That doesn't count the ones we've built for others.

Honestly, I'm the happiest when I'm in a trackhoe digging a pond and building filtration. There's nothing like seeing that first drop of water hit the liner.

06-17-2011, 03:38 AM
I do know what you mean there. Trackhoe sounds so, um, massive. I've run 'em, but not in my little yard. Takes all the fun out of it.

06-17-2011, 09:01 AM
Well, we have 7 acres so there's nothing like hydraulics and a woman! LOL I don't have the strength you men do so they come in handy. When we have one around, I have to fight the guys for my turn.

DH won't let me on the dozer. I don't mind operating them but it's really scary pushing down an 80-100' tree with it. Did it once and that was enough.

06-20-2011, 04:42 PM
Now that I have been specific on my setup once again I want to be ceratin about the placement of the check valve and ball valve.

I have decided to go with a 4" aerated BD with all your folks advice. For now I will continue on with the other plumbing at hand until I get the bottom drain.

Having gotten the BD issue all clarified I have enclosed pics below to address the check valve and ball valve before I go with glue.

I want to know if the check valve is fine where its at right after the pumphouse then followed by the ball valve then the stock tank.

I had to put in a couple 45's to make that curve going to the ball valve possible into the inlet pipe of tank. Sorry bout the shadows but mother nature wasnt cooperating.

Am I going to be alright with this setup, any suggestions, comments, all welcome. Thnxs again for all your help TPF

06-20-2011, 05:03 PM
If I were you, I would change out those ball valves to ones with unions so you can unscrew them and remove them if A) anything gets stuck in the pipe; and B) you need to take parts of you system apart. For example, what if you need to detach your stock tank from your piping because the ground has settled and now it's a tad uneven. Well, that's a real life example that happened to me. I needed to move it just a smidge to rebalance it, and thank goodness I had those unions or I would not have been able to get things apart. You could also just cut the pipe and put a rubber fernco fitting in, and that way if you need to remove the tank or anything else, you can just open the fitting.

06-20-2011, 05:20 PM
Lisa I keep hearing alot about those Fernco fittings throughout this site....Do they attach with those metals screw clamps? What about leaks with these ferncos, any problems? That curve in the pvc right before the ball valve was a 'mother' let me tell you. I'm still not quite satisfied with it.

Your right anything with unions is a whole lot better in case of unforseen problems like you have had in the past. I will either go with unions or fernco like u suggested. I am sure once I get the stock tank filled I could have settlement problems as well even though its on a slab of cement followed by blocks.

I still have the receipt for the ball valve and I'm either going to take it off and exchange it for one with unions or keep it and go with a fernco. I will let you know and insert another photo on what I decide on.

Any comments on the placing of the check valve? Thnxs Lisa

06-20-2011, 06:09 PM
Yes, they attach with the clamp. I have one in between some 3" pipe to my stock tank and I have never had a leak issue. You just tighten it as far as it will go, and that's it. If you're going to put a fernco on, you keep that ball valve. You still need a ball valve to stop/reduce water flow when necessary.

06-20-2011, 06:48 PM
Correct Lisa, got it and the check valve is okay where its at?

06-20-2011, 07:43 PM
Lisa what size pipe it your outlet coming out of your tank? I have 2" inlet pipe and a 100 gal tank....

06-20-2011, 08:27 PM
I have a 150g stock tank and the pipes are 3". I upside the 2" pipe coming from my pump, and then the exit pipe is 3". I also have two 3" BD's on my 5k pond. Yes, our check valve looks fine to me. As long as the arrow is facing in the proper direction for water to travel, you are good. On my old pond my check valve was horizontal the way yours is depicted (never had any trouble) . On my new pond, my check valve is vertical because it's on the outlet of my pump.

06-20-2011, 09:53 PM
My inlet is 2" pipe so I think I should be good with a 3" outlet pipe for a 100 gal tank...my pond is 15'W x 20' long also I am thinking when I get to that point I made need to go with 2 BD's since one BD (4") would be at the deepest end of the pond and I think I would have 'dead' spots without any water current to clean out the shallow end, the pond floor is sloped though. Just a thought........

06-20-2011, 10:07 PM
Yes, you'll need 1 BD at each end, about 8' from the ends. They only draw about 8'.

Lisa is right about the double union (very expensive) or just put about 1' of pipe on each side of the valve and use Fernco's to attach them. That way, you'll always be able to reuse the valve.

06-20-2011, 10:14 PM

06-21-2011, 01:05 AM
Sandy you are right about $24 for a double union ball valve at local home store.. I think I will stay with ball valve and use 2 ferncos alot cheaper that way.. Thnxs ladies

06-21-2011, 02:30 AM
Those Fernco fittings flex a good bit, too, easing your install in tight spots. They make 45 degree angles, that can be SO much easier than those hard fittings you've got. Plus, you can reuse the fittings and the pipe if you ever want to expand the pond or reconfigure for any reason, with no cutting or re gluing.

Hope it works well for you, you're definitely on the right track.

06-21-2011, 08:05 AM
Just don't use 90 degree fernco's on the outlet side of a pump. They will blow off.

06-21-2011, 07:12 PM
I bought these today....I will use them on that tight area I am having problems with before and after the ball valve right.

06-21-2011, 10:32 PM
You'll love these things.

06-21-2011, 10:44 PM
I'll take some pics when I put them on since I know how we all like pics on this site

06-23-2011, 03:18 PM
This is what I have done so far with the plumbing work, the check valve with ferncos, the curve area, and the ball valve with ferncos. Let me know what you think. Thnxs

06-23-2011, 05:39 PM
So far that all looks good to me.

06-23-2011, 07:16 PM
Lisa so I should be able to go to glue stage at this point yeah?

06-24-2011, 01:03 AM
Glue it is! Looks great, and easy to maintain (if necessary).

06-24-2011, 08:36 AM
Yeah, it looks like you are ready to rock with glue to me.

06-24-2011, 10:33 AM
Thanks Will n Lisa :happy: