Does the Quiet Check Valve Eliminate Thunk Sound from Sump Pump?

[@michaelwells203]

HOW IT WORKS. The larger housing diameter and slanted exit angle create a turbulence withing the valve housing. The turbulence crashes into the briefly backflowing water just long enough to allow the flap to close quietly. Pretty smart idea.

[@Techhead777]

Thank you for your video. I was doing a sump pump replacement and had the standard noisy 1 1/2 check valve make that thunk sound. I bought the McDonald valve at my local plumbing store. After reviewing your video I returned it for a Zoeller quiet check valve. Zoeller and Campbell make the clear see through valves with the screw on compression fittings. The Magic has the rubber clamp style fittings. Zoeller makes one in opaque which is what I bought. I think the other brands are knock offs of Zoeller and I don't know how long they will last in comparison. Great valve though, super quiet and no thunk.

[@theclearsounds3911]

OK, yet another explanation on how it works. The loud ones rely on back flow of the water to close the valve. Since the flap won't close until the water starts flowing back down at a fairly high rate of speed, and water is heavy, there will be quite a force of heavy water when the flap finally closes, causing a bang. The spring on the quiet one closes the flap before the water starts falling quickly, so it's stopping the water with much less momentum, and therefore less force. As someone else pointed out, the angle and turbulence have something to do with it also. The 1/2 pound force of the spring is very easily overcome by the pump motor, which can push much harder than that. Very clever idea, as long as that spring doesn't rust quickly!

[@KameraShy]

Exactly. That is what I was thinking.

[@RobertMichiels-o8g]

It works because the spring starts to close the flapper before the water stops flowing. Once the pump stops the water for a brief moment is still flowing forward then stops moving forward there is obviously a pressure drop which the spring is designed to close the flapper even though there is still water within the valve chamber and outside the valve chamber in the pipe so there is not a slamming of the flapper into the seat which causes that thunk noise. Because the spring closes the flap against the water it actually acts as a cushion as a soft close as opposed to a hard close.

[@KameraShy]

I had to replace my sump pump and while the conventional check valve was noisy thought I would try a "quiet" valve. I picked up the "Basement Watchdog Klunkless Check Valve" at Home Depot . It was expensive. Unfortunately it is 10 times noisier than the regular one. Huge clunk and the pipe and whole house rattle. Wakes me up at night. I will try this one. Thanks.

[@rhettoracle9679]

Silence is golden! In boats, we use expensive stainless steel hose clamps ( on the cheaper ones, the band is stainless, but the tension screw is not, will rust out and the band release, hose leaks or falls off, boat sinks.) This is "mission critical" so two bands are used in each connection ie back up redundancy. Peace

[@paulc3125]

How is it supposed to work without the spring? It opens all the way up and folds into the wider opening so Without the spring sometimes it would close and sometimes it would stay fully open.

[@Ronniejamesleo]

I bought one from amazon beings my friend never had one installed on the pump when she bought the house. It will now 👍

[@petervonpanda]

I think you'll like it! It was such a game-changer. Went from noise that would wake you up to being nearly silent!

[@Howard10Howie]

The disk pushes and closes the valve before back pressure can start. Removing the slapping sound!

[@petervonpanda]

Good explanation

[@t.chavez8623]

Very quiet! 👍

[@Slifer715]

I bought one similar by ay mcdonald sump pump check valve but i have a sewage ejector. Will it still work for my system? Im annoyed by the loud thump ive been hearing

[@Slifer715]

By the way the check valve i got is for 2inch pvc

[@petervonpanda]

I love this valve. Not sure if it’ll work for sewage but it’s great for my sump.

[@Z-Ack]

I dunno if thats a quiet check valve.. you might have rubbed off the “not” at the beginning of the label. Otherwise you wouldnt know what you got.. do they make “the loud check valve”?

[@pepperj]

So mine got rid of the Thump but now I have this equally annoying loud gurgle/farting noise when the suction starts. Any idea?

[@gg.6967]

If your pumping effluent or greywater then put a 1/8 hole in the discharge line just above the pump volute. If the discharge is sewage then place a 3/16 hole in your discharge pipe above the volute. 1.5" above the volute for a 1.5" pipe and 2" above the volute for 2" pipe. The pump will stop moving and the gurgle will stop as well. Use a cheap drill bit from harbor fr. or HD but do not use just any size laying around the house.

[@gg.6967]

Your check & pump are functioning properly.

[@pepperj]

@@gg.6967 thanks for the reply. I believe since the previous owner has the sump hooked to the sewage line, im hearing the vibration and water in my house (mainly from the bathroom tub since its directly above the pump in the basement). so you think the drilling in the pipe will stop vibration of pump?

[@coltfiggins2840]

Silly Boy, if you install horizontally, there might not be enough back pressure to get that flap closed, tight; all the way.

[@b0neme]

You said you didn't know how the 1/2 lb spring of that unit is able to work? The area of the port looks like at least 1". Standard water pressure is 60-80 lbs/sq in. I think a 60 lb rock could overcome a 1/2 lb spring tension...no?!

[@SL_Hugh]

You are talking about pressure on the input water line. Here the pressure what your pump generates. If it can raise water 10', that corresponds to ~5 lbs/sq inch. Way less than pressure of your water supply, but still plenty to open the valve.