Koitoilet II Bottom Drain ABS?

[Dzway]

Hi!
Just looking around for bottom drains and I found this on ebay...
http://www.ebay.com/itm/Koitoilet-I...t=LH_DefaultDomain_0&var=&hash=item7dbce8ac4d

I want the 4" but I notice its made of ABS (the 3" is pvc) can someone tell me the difference?

My hardware store thought I was crazy when I asked for 4" PVC Ball Valves. Anyways, they didn't have any but made some phone calls, while I was standing there and their suppliers didn't have any. He said they would put a call out to the big boys but I haven't heard anything back yet.
So I found a couple on Ebay, for $79.00 EACH (free shipping), Valterra 4" Knife Valve PVC SlipXSlip with Stainless Steel Blade Gate Valve and 4" PVC Ball Valve SlipXSlip (what does SlipXSlip mean)
Should I grab these? Or can I find these cheaper?

Thank you!!



ps. I ordered my liner, I pick it up next week!! So excited!

 

[don't ask]

abs doesn't use primer and no waiting/holding pieces together after adding glue..

slipxslip should mean pieces fit inside one another as opposed to screwing together fittings

no clue on pricing...

yes 4inch ball valve is probably unusual as my guess is you will be reducing as you get to the pump..i would run 4inch from drain to say water level of pond roughly and then go to 3 inch pipe and valve and then to 2inch i would think for pump connection

 

[Waterbug]

ABS and PVC are 2 different kinds of plastic. PVC can generally be used in higher pressure applications. ABS often floats, PVC often sinks, but this depends on the actual formula. ABS is generally cheaper than PVC. Pretty much all plumbing for a pond is considered low pressure.

$80 for a 4" PVC ball valve is a good price. About right for a knife valve. You need a specific transition glue to join PVC and ABS slip joints.

Retail type hardware stores only carry products used by "normal" type homes. Plumbing supplies would have 4" and larger PVC ball valves and not think it an unusual product, although they don't sell them everyday.

With a little design work there shouldn't normally be a need to have any valve on a BD.

 

[Dzway]

Thank you for explaining the difference between the two for me.

Waterbug, I live in upstate NY (winter weather) shouldn't I have some kind of valve on the BD line so I can shut it down for and blow it out for the winter? Thanks!

 

[Doug_S]

ABS has a low resistance to UV rays so it is not recommended for use in places where it will be exposed to the sun.​

 

[Waterbug]

Waterbug, I live in upstate NY (winter weather) shouldn't I have some kind of valve on the BD line so I can shut it down for and blow it out for the winter? Thanks!

Ice expands, 9-10%...that's a lot. There is no way any pipe can handle a 10% expansion. But you can do an interesting experiment...cap one end of a pipe (any material), filled it with water and placed it in your freezer. Didn't burst! But you'll probably see ice popping out the top.

Pipes burst not directly from ice but from a large pressure increase inside the pipe caused by the ice. In a water supply pipe the ice forms and causes a blockage. As the pipe continues to freeze the water between the ice and the closed facets in the house gets compressed and the burst happens some place in that section of pipe, not where there is actually any ice. Water pipes almost always burst inside the house. It isn't an expansion in diameter, it's the expansion of ice along the length of the pipe that acts like a ram compressing water to higher and higher pressure.

This is also why people will run a facet a bit to keep a pipe from bursting. One it allows warmer water into the pipe, but also allows water to escape should the pipe freeze anyways should flow not be enough.

Another way to see it...picture ice forming inside the pipe, it doesn't freeze solid all at once. As the ice freezes the opening of water gets smaller and smaller until there's just a channel of a few molecules of water remaining. At this point the ice has expanded, but it has done this by pushing water out of the way, not by pushing against the pipe. So when that last channel freezes the ice plug is exactly the diameter of the pipe and is not pushing on the pipe at all.

A BD drain pipe is open at both ends. As ice forms it pushes water out the top or back into the pond. You can get into problems with complex joints above ground and what not. I think adding a valve only increases risk.

There are ways to plug the bottom drain and "blow out the line" but it's complex and a lot of work imo. Plus what if there's a tiny leak in the plug? And/or if you get a freeze deeper than you thought, you have a plugged BD, an ice plug below the ground, water in between freezing and increasing pressure. To me that sound like a burst pipe.

To me a valve on a BD pipe can only increase the chances of a burst pipe.

 

[Mucky_Waters]

I always though that was how people winterized their bottom drains.With a shut off valve at the top end where the bottom drain lined exits the pond and having another smaller line to blow compressed air in the line to push the water in the main line back into the pond and close off that valve to seal the "air" in the main line???

 

[Waterbug]

So the valve is like 4' below ground level but also insulated some how? Some kind of air fitting is placed on the pipe outflow to seal it?

I've read people do this but have never run into exactly how it's done.

 

[addy1]

We don't get as cold as you do, the first winter with the pond, the pond froze 8 inches down. We had the bog line full of water, pump lines from the bog sticking out full of water, the ends of the lines where open. Nothing broke. I unhooked the pump, totally forgot about the lines sitting there with water in them.

This winter was warmer, a lot warmer, left the water in the lines, still no issues.

 

[don't ask]

i use a bottom drain but ran it last winter so i don't have a long history.. i also have a valve on my pipe but that is only to shut off water coming to pump if i needed to replace my pump or add another feature so water will not continue to drain or to slow the flow of water coming from my bottom drain and have skimmer pull more water

 

[Mucky_Waters]

So the valve is like 4' below ground level but also insulated some how? Some kind of air fitting is placed on the pipe outflow to seal it?

The problem with bottom drains in the winter is the water line from them comes up above frost level where it conects to the rest of the filters tanks, seives, pumps,,,,, whatever. Most people want to shut all that stuff down in the winter and drain it, but to do that you have to have a valve to close off the water coming from the bottom drain, and that is usually located above the frost level, so it runs the risk of freezing when it gets cold if there is standing water in it. so you either have a way to stop it from freezing, or get the water out. So if you put a small T line with a small valve on the water side of the main shut of and have a way to to blow compressed air in there you can force the standing water in the line back to the pond and fill the line with air, then shut the smaller valve and there should be nothing but air in the line above the frost level, and no risk of water freezing and cracking the pipe.
I went the other route with my bottom drain line and have it enclosed in an insulated room where it will (hopefully) never freeze.

 

[Waterbug]

Yeah, that's kind of how I thought it would have to work, just never actually read it any place. But maybe everyone is doing this.

Seems like a lot of work and expense to me and not needed. Ball valves are not rated for air pressure. I suppose some will hold air pressure, but I assume most will slowly leak and the water will come right back in. There are specific valves for air. But that's probably not a problem because I'd assume the water will freeze at the valve first and freeze down pushing water back into the pond so there's no danger of a pipe bursting. The only time there would be a problem is if the pipe could freeze downstream of the valve and then freeze toward the valve. But that would be a weird layout, like an over the pond side type deal.

 

[Mucky_Waters]

Yeah, I wondered about the air leaking past too, but when I asked in the forums about how they stop the line from freezing that was what I was told how they do it. I may try it this winter just to see, even though mine is indoors I did install an auxiliary valve just before my main gate valve.
As for it not freezing because the ice would just push the water back, I don't really think it works like that 100%. It's true that frost valves will burst back inside first where the water is, but I have seen straight pipes crack from the ice before, even when they had ways for the water pressure to release going both ways, and drain traps will almost always crack from the expanding ice, and they have no water pressure at all.
So yeah, 99% of the water gets pushed back as the water freezes, but that last 1% of expansion after the water is a solid is often enough to crack a pipe.
Last thing I would want to see is my pond drained through a broken 3" line in the dead of winter. :sad:

 

[Waterbug]

For those interested I Googled "frozen pipe burst" and this was the first hit. Lot's more places describing how it works.

 

[brandonsdad02]

I don't have a bottom drain, but all of my plumbing is done in PVC pipe. I put rubber couplers in 2 spots so I could take my pump out and right before my pvc goes into my bog. My hopes are that when the water freezes in the bog, it will just push the ice thru the pipe and out the open end. The other line I'm going to blow out with air and see what happens. I do know that warm water will freeze faster than cold water. Not sure how, but I have tried if before with filling ice cube trays and the one with warm water froze faster than the one with cold water.