View Full Version : Sewage check valve mounting

01-31-2006, 09:09 AM
I'm installing a sewage ejector pump in my basement.
I need to install a check valve between the pump and the sewer line.

The pump manual says to mount the check valve horizontally to avoid solids settling atop the valve and causing it to stick.

However, I purchased a rigid pvc cv that seems much sturdier than the 'economy' cv the pump mfg recommends using. The pvc valve mfg says it can be installed vertically or horizontally. In fact, they say vertically is better because it lets gravity work better to seal the valve AND it actually says the column of water atop the valve is a good thing for preventing b-flow and won't cause the valve to seal or a pump to burnout.

Who do I believe? The pump manufacturer or the valve manufacturer? BTW, I'm partial to vertical installation bkz it'll make removing the pump for servicing easier in the long run.

Also, my pump is about 10 horiz feet from the stack. Any problem with lifting the discharge straight up, and running 10feet horiz (with appropriate pitch) to the sewer (or do I have to position the pump as close underneath the sewer outlet as possible?)

I'm using a 2hp / 2"discharge pump.

01-31-2006, 12:57 PM
Never mind. I read a few pump manuals from Little Giant and Flotec. They both recommend horizontal mounting of the check valves.

It seems that if the valve is used in a water system only, then it might be preferable to mount vertically. However, in systems pumping solids, the risk of solids getting lodged atop the cv in a vertical mount is greater than the risk of the valve getting accidentally stuck open in a horizontal mount, so it's better to mount horizontally.

Anyway, I'm going with that. Any counter-opinions?

01-31-2006, 09:15 PM
Install the check valve vertically, with a knife or ball valve directly above it. The valve above the check will help to keep you from 'wearing yesterdays lunch' when you actually have to service this pump.

I can't say that I've ever seen a check valve plugged in such a way.

Hopefully your pump is a Goulds or at least a Zoeller. Anything else is crap, pardon the pun.

02-01-2006, 06:20 AM
Why a two horsepower, do you have a bowling alley in your basement? I'll bet you bought the Flotec didn't you. Don't believe the two horsepower if you did. I agree with the vertical valve install.


02-01-2006, 06:43 AM
I meant 1/2 hp.
Yes, I bought a flotec. It seemed to be the best of the 'lower priced' brands (Wayne, LG, etc).
The pump is cast iron, and pretty quiet. If it burns out, I'll replace it with a better model. I didn't realize Zoeller was so highly regarded when I purchased, else I would have gone that route.

I've been reading that either vertically or horizontally is fine. Although I read one bldg code in another state that prohibits vertical mounting.

02-01-2006, 07:34 AM
It doesn't matter which way you install one of our check valves, vertically or horizontally is perfectly fine! ;)

02-01-2006, 07:36 AM
That's better. I wouldn't believe the 1/2hp either. It's more like a 1/3 I'm sure.

Here; Lowes sells Myers pumps under the Water Ace name. The same pumps I sell under the Myers name. The difference is all of Lowes 1/2hp are my 1/3hp and the 3/4hp's are actually the 1/2hp. I don't know how they get away with that sort of false advertising, but they do.


02-01-2006, 07:55 AM
I do not know how your PVC valve is made, but the ones that come from Zoeller and most other pump companies have a rubber disc to minimize the shut off "hammer" sound.

02-01-2006, 08:45 AM
Yup, the valve has a rubber disk. I cycled my system a few times yesterday, and I can't replicate the hammer I hear a lot of people complain about.

Ok, here's another question:
Why do the pumps require a 3/16" hole in the discharge pipe? They say it prevents the pump from airlocking, but what does that mean?

Also should that hole be above or below the waterline in the sump basin?

Bob NH
02-01-2006, 09:43 AM
Air locking can occur if you get air in the line and it forms a bubble against the check valve that extends down to the impeller of the pump. It that happens, the pump won't pump. The hole lets the air out, and some water when the pump is on.

It should be above the high water line but below the edge of the sump and below the check valve because there will be a stream of water coming out when the pump is on.

02-02-2006, 06:53 AM
Air locking is like taking a glass upside down and putting it into a sink full of water, the water can not enter up into the glass because the air has no where to go, but if you had a hole in the top of the glass so the air can escape, it will allow the water to go up into the glass. :D