Water Hammer

[Floyd]

Hello everyone, I'm hoping someone can help me with an issue that I have.
I have a new keg set up using ball lock kegs. I have a dual faucet with about 6' of line to the kegs and another 6' of gas line to the manifold.

I am getting a water hammer so bad when i close the faucet it has brocken all of my duotight fittings once and just broke the fittings off my manifold again.

Has anyone experienced this and how did you fix it? My thought is to clamp my lines down as they are just hanging loose now.

 

[mashdar]

Beer hammer? From the faucets closing? Are they spring return?

I have not heard of this, but you must be getting high flow and sudden closing of the valve. Close the valve more slowly?

What size lines are you running? What pressure?

 

[day_trippr]

Greetings, @Floyd, and welcome to the forums at homebrewtalk.com

Not only is that the first time I've seen the "exploded view" of a Duotight fitting I've never read of anyone having "hammer" issues with dispensing. What Inside Diameter tubing are you using and what type of faucets?

fwiw, I use the 4mm ID EVABarrier for beer with 6.5 foot runs from kegs to shanks with forward sealing Perlick faucets and in 16 years of dispensing home brew I don't recall ever thinking "Hmmm - that's beer hammer happening"...

Cheers!

 

[mashdar]

Also what faucets? And any check valves in the beverage side? Maybe faucet is smashing beer into a check valve somehow?

 

[Floyd]

Also what faucets? And any check valves in the beverage side? Maybe faucet is smashing beer into a check valve somehow?

Im using the same tubeing with no check valves and I have the rear closing taps. For pressure i only have 12 psi on the beer keg and 22 on the water keg.
A plumber i know suggested the same thing, to make sure i close the valves slow and clamp the lines down.
But i havent talked to anyone haveing the same problem.

 

[mashdar]

Do you hear the lines slam? Could it actually just be weak duotights? I've heard they are acetate and sensitive to some sanitizers.

 

[Floyd]

I can hear the pressure slam in the keg and after the first fittings went i only use soapy water on them.

 

[hotbeer]

Probably the problem is plumbing in your home that you have it connected too. If a old house the hammer breaks they built into it might be water logged. Essentially all the air in them has been absorbed into the water over time. So there isn't anything to cushion the sudden stopping of the water.

The fix for that is to turn off the household water and then drain it from the lowest point. But even that may not get the water out of the lines that have the hammer brakes if their routing doesn't let them clear by simple draining.

You could make a brake to put in between by putting a tee in the supply line and running a piece of pipe vertically that is plugged on the end to hold the air in. The larger diameter or longer you can have that vertical pipe with air, the better the cushioning. Fasten it to the wall or something secure. It'll jump quite a bit depending on how much water rate you are stopping the flow of.


EDIT:
Oh wait! This is in your kegerator? Never mind about most of what I wrote. But still you can make a accumulator with a piece of pipe to put somewhere in it to cushion the sudden stopping of whatever it is you are stopping. Though if CO2 is involved, it might be better to buy a accumulator for plumbing that has a diaphragm to keep the air and liquid separate.

 

[Broken Crow]

That's just plain wierd! Can you post a pic, maybe tell us more such as what make of regulator you're using? It really sounds like some kind of 'sudden high-pressure' event that I just can't make any sense out of... Is it the beer tap or the water tap? How long have you been using this system and is this a new behaviour and different from previous?

 

[Floyd]

Linked below is the system im using. One keg for water and one for beer. The first set of fittings lasted around 5 months, the new manifold fiitings lasted 2 weeks. The hammer was very noticable this time. The last time i had no indication something was qrong.

I did have one person suggest to me that when i hear it once to drain the liquid line and then hook up again. They seem to think co2 is coming out of suspension while its sitting in the line. Does that make sense to anyone?

https://www.graintoglass.ca/collect...l-regulator-beer-tower?variant=37522531385541

 

[mashdar]

Do both faucets do it?

 

[Broken Crow]

Thanks for the link! Gives me the following assumptions; You're an adept DIY'er. The 'beverage line' is probably the 3/16"ID Bevlex 200 they also list on thier site..(apart from O2 permeability it's still commercially a 'standard' line). They have a drop-down option for faucet but only Nukatap's in the list, so presumably they sold out of the rear-sealing taps in the picture which I'm guessing are they ones you have. I honestly have no idea if the taps can cause such a a thing as I only own one rear-sealing tap because it came with my first kegerator and I've only ever used it as a wrench for installing new shanks in my tower and won't let it touch my beer.
Maybe someone else who uses those less-hygienic taps can wiegh in here.

 

[Broken Crow]

Yeah; What @mashdar asked... Plus: Welcome to HBT!

 

[Floyd]

Both do it, although the beer line is much less. The beet only runs at 12 psi though and the water at 22.

I'm hoping clamping the limes down will take the pressure of the fittings.

 

[Broken Crow]

Clamping the lines down might work, but that is treating the symptom and not the the problem. I know from reading this site every day that like me, the posters who have so far responded are now engaged in trying to wrap our heads around this totally new phenomena you've gifted us with. On the one hand; Thanks for the interesting problem to solve!! ...On the other; ....hmmmm....this is really puzzling! Can you take som pics of the whole system and post them? Maybe a video of the behaviour? My brain is engaged and I really want to understand this.

 

[mashdar]

How do you clean and/or sanitize your beverage-side components?

The apparent beer hammer may be due to unusually floppy install, and fitting failure may be unrelated or partially caused by repeated physical stress.

Star san may cause the duotight plastic to get brittle, e.g. https://www.homebrewtalk.com/threads/duotight-fittings-disintegrated.703071/

 

[Broken Crow]

Is the pour steady, or does it vary or spurt while filling a glass? My intuition suggests the diaphram in the regulator is wobbling or something, but logic tells me the keg should act as a kind of capacitor, but I also have brain damage and both my intuition and logic have been dead-wrong a number of times in the past ten years plus I really don't think a regulator can behave in such a manner. @day_trippr groks regulators better than most of us on here, maybe he can dismiss this idea, but hammer is a pulsating pressure and maybe pics can help someone see how it's happening.

 

[Floyd]

I wont be able to post a picture of my set up until i get home tonight. As for it running, the fittings that broke are the ones my brew store are out of right now lol...of course.

And yes the install is as floppy as a wet noodle, i didnt even think of securing any lines. All lines are loose and flopping around.

 

[Floyd]

This is my set up for now unitl i can get a old freezer up stairs. Im going to hold off on that until i can solve the hammer problem

 

[passedpawn]

I'd suggest something else is wrong here beyond water hammer. Sorry, I know that's not too helpful.

Water hammer is the force caused by the momentum of a fluid changing abruptly. Momentum is mass times velocity. When velocity changes, that's acceleration - anyone who's had physics at any level knows that mass*acceleration = force. That force is water hammer. But without significant mass, the force from water hammer is small and unlikely to break fittings.

I was a fireman a long time ago. The mass and velocity of the water shooting through an 60psi 8" underground pipe, through a hydrant, and to the end of a 2.5" fire hose is huge, and when the bail is slammed down you definitely can make that hose jump off the ground. The mass of beer flowing from a 12psi keg through a piece of 3.8" tubing is quite small. So, force from water hammer quite small too.

 

[scrap iron]

"They seem to think co2 is coming out of suspension while its sitting in the line. Does that make sense to anyone?"
You stated this in one of your posts. My question is how long had the kegerator been sitting not in use. I ask because this happened to me recently. I don't drink as much as I used to and the kegerator sits for several days. When I drew a glass after sitting it had a little hammer but cleared up after a couple beers. I have forward seal taps with a spring return. I worked the tap off and on several times, and it hadn't happened since. I figured it was co2 coming out of suspension in the line.

 

[Floyd]

I hope you just hit the nail on the head. My lines can sit for days without being used, especially durring the work week.
Once i get the new manifold fittings I'm going to test that out if it starts again

 

[FloppyKnockers]

The apparent beer hammer may be due to unusually floppy install...

I don't remember doing this, but most of my installs are fairly usual.

It's not odd to me that the 22 psi line might fall victim, but not the 12psi one. That said. I know built-in coffee machines sometime have this problem and you can install a 1/4" hammer arrestor.

I would also try tightening the bonnet nut on top of the faucet. If the handle is loose, it's much harder to close slowly.

 

[Broken Crow]

from the pics; Congrats! You have the forward-sealing Nukataps and the line looks to be EVABarrier.
I was hoping to see pics of it hooked up for operation in the hopes that might reveal something...where's the gas-line?
Just to dismiss it; When you open the valve on the CO2 tank, are you opening it all the way, or just until it's pssing gas? ...if you didn't know; most CO2 tank valves need to be fully opened and I'm wondering if there's a flopping o-ring on a partially open valve. Is you beer carbonated at without refridgeration?

 

[Floyd]

The CO2 tank is indeed opened fully and the beer isnt refrigerated. Lots of Ice packs to keep the temp down and my basement is fairly cool which also helps.

Thanks for the info everyone and it looks like it is indeed the carbonation coming out in the lines. What that is doing exactly I cannot say but it isnt good lol. I finally got new fittings installed, didnt change anything in my set up and no water hammer coming from either line. For fittings sake if I dont plan on drinking any beer I will disconnect the liquid line and drain. As for the soda water I will just drain some every now and then to make sure it stays good. If I happens again I'll confirm draining the lines fixes it and post an update.