Water Hammer - Well pump to storage tank to Shallow well booster pump

[JohnnyAirtime]

Good day...

Came upon this site, doing some research and getting conflicting results. Seems everyone here has a similar mindset and are experienced in the issue I'm having.

Here's what I have;
A deep well (500ft), that pumps water up to a 20K gal storage tank. No float valve on the tank, so I manually turn on the well pump via a circuit breaker until the tank overflows. I bought the house with it setup like this... it works. A PITA sometimes (like when I don't see/hear it overflowing!), but it works.

The storage tank, gravity feeds water to my basement (yup, I have a basement in San Diego, CA!) via a 1.5" line. In the basement, is the Goulds shallow well pump (jet pump) that is being used as a booster. about 4ft before the pump, in the suction or supply line to the pump is my check valve. On the output side of the pump, it T's off and supplies pressure to several lines and a 40gal pressure tank (the pressure tank is set a few lbs less then my turn-on pressure switch).

I used to get water hammer in the output side of the pump in the house's pipes when the pump turned on. I had to do some re-piping (due to drips, and poor plumbing practices - which drove me nuts) and at the time replaced my check valve (the check valve was located in it's same spot when I bought the house, I didn't move it - just replaced it as it seemed faulty when I removed and checked it) and my pressure tank (due to the bladder being compromised). The pump "ON" water hammer is gone and hasn't come back since my repairs. Not too long after those repairs, I got water hammer at pump "OFF".

The check valve I used, is a spring operated unit from good 'ol Home Depot. Not sure if it's adequate, so I'm open to options if you all deem it "not worthy" of handling the pump off, and it possibly slamming shut, causing my hammer(?).

Now that you know my setup and what I got from the original homeowner, and what I've since done to the line. Pretty basic. Let's continue...

In my reading, a pump manufacturer suggested the check valve be as close to the water supply as possible. In this case, I'd be putting a check valve just off my storage tank about 200 ft. away. In doing so, it said that will keep my pump from starving or cavitating. Which I don't think it's doing with the check valve only 4 ft away from the pump's inlet, but again... I'm hopeful if I move the check valve, the water hammer will go away? But in doing so, I'm now pressurizing the entire run of pipe back to the storage tank... correct? Not worried about it, just not sure it's what the pump wants (I don't speak "pump" language). Hence one of the many reasons I'm here.

So... the questions are;

1. Do I need to upgrade to a better check valve? If yes, please recommend one!​

2. Do I move the check valve, from 4 ft away from the pump to 150 ft. away at the water source (storage tank)? Or will this just move my water hammer issue, from within my basement (+/- 50ft of pipe) to now the entire length of pipe 150-200 ft away?!

3. I've read a lot about CSVs (Cycle Stop Valves), and they're just damn confusing. But I can see how they work. Not sure it'd be helpful in my case, as I see most use them for well pumps/pressure tank setups. Not where a "booster" pump is being used. Am I wrong, or would it be beneficial?

4. Should I be making my own arrestor? By T'ing off AT the actual input of the pump, and creating a water/air trap with 12" of vertical 'capped' pipe? I know how plumbers do it in wall for hot/cold at the shower, and I thought about the same concept but in 1-1/4" PVC (the input size of my pump). Seems that's a band-aid, and may/may not work anyway.
​

If none of this makes sense, I can draw up a picture/sketch.... but, that might be just as confusing. I'd have to use Visio or something to make it look professional (per my OCD).

I'm all ears. Please enlighten me before I go nuts trying to cure this hammer issue.

 

[Reach4]

I wanted to confirm a couple things from my reading of your post:

1. You have only the one check valve after the open-to-the-atmosphere tank, and that is 4 ft before the jet pump.
2. Your only symptom listed is a bang when the jet pump turns off.

 

[Sponsor]

 

[JohnnyAirtime]

I wanted to confirm a couple things from my reading of your post:

1. You have only the one check valve after the open-to-the-atmosphere tank, and that is 4 ft before the jet pump.
   
2. Your only symptom listed is a bang when the jet pump turns off.

1. That is correct. Like this;
   Storage tank ----200 ft----> check valve ---> 4 ft ---> jet pump ---> 4ft ---> pressure tank, house water supply
   
   
2. That's correct. About 2 or 3 bangs, at pump shut off.

 

[Reach4]

On #4, I suspect you have something there. However if you built one, I think you would want it longer. Plus those old style hammer arrestors suffer from the air getting dissolved in the water. You would want a way to drain out the water periodically. Alternatively, how about a thermal expansion tank or small pressure tank? The air precharge would be dropped to near zero so as to not be more than the static pressure at that point.

On #3 I expect a CSV would work fine on the jet pump. Due to the way it works, the water flow would drop before shutoff. So I expect the water hammer would be reduced, or maybe even eliminated.

 

[JohnnyAirtime]

On #4, I suspect you have something there. However if you built one, I think you would want it longer. Plus those old style hammer arrestors suffer from the air getting dissolved in the water. You would want a way to drain out the water periodically. Alternatively, how about a thermal expansion tank or small pressure tank? The air precharge would be dropped to near zero so as to not be more than the static pressure at that point.

On #3 I expect a CSV would work fine on the jet pump. Due to the way it works, the water flow would drop before shutoff. So I expect the water hammer would be reduced, or maybe even eliminated.

About #4... I know it's somewhat of a crap shoot to build my own arrestor, and the worse I can do is fail costing me $5 in PVC parts. So I might try it this weekend and see what happens.

I can also pickup the thermal tank ($40 at Home CheapO), and parts... to have it on hand in case the PVC arrestor doesn't work out. And if the thermal tank doesn't work, return it and whatever costly brass fittings I have to use. I'd think eating a few parts of PVC cost isn't a big deal.

So... which should work? Just bypass the DIY arrestor idea and go straight to the thermal exp tank?

About #3... the more I read, the less I like the idea. I watched THIS graphic and I'm not sure I'd like my pump to run constantly (if using lots of water all at once). And, I'm okay with water pressure varying from 40 to 60psi. I can see the benefit if I didn't have a huge storage tank and was getting water directly from the well pump. In my case, not sure it's cost effective (to simply aid in my water hammer issue). Plus, I'd be hoping one of the above #4 options work out.

So, nothing on #1 and 2 ?

 

[Reach4]

About #4... I know it's somewhat of a crap shoot to build my own arrestor, and the worse I can do is fail costing me $5 in PVC parts. So I might try it this weekend and see what happens.

48 inches is the same price as 12 inches for practical purposes.

A small valve to admit air, or even a plumbing plug, would let you admit air into a non-pressurized water line. A Shrader valve would let you insert air, even into pressure.

A pressure+vacuum valve on the input water could be interesting while you are making changes.

 

[JohnnyAirtime]

48 inches is the same price as 12 inches for practical purposes.

A small valve to admit air, or even a plumbing plug, would let you admit air into a non-pressurized water line. A Shrader valve would let you insert air, even into pressure.

A pressure+vacuum valve on the input water could be interesting while you are making changes.

I get it... but I don't have 48" to work with.
My jet pump is on a shelf/stand at almost eye level (I'm 6'3") in the basement. And the supply is routed above attached to first floor joists, leaving at max 12-16" of space with couplers and Ts before it hits my floor joists.

Putting a schrader valve in the end cap of the DIY arrestor is easy, and could be useful to attain a volume of air as a cushion. But, I'd honestly need a clear pipe as that's a moving target to attain perfectly. Especially if my water pressure is not constant, which I noted it's 40-60psi

But again... would it work? Sounds like it should... but, I'm skeptical.

I think what I'll do, is step by step.

Step 1 - remove the local check valves (near jet pump), and install a check at the storage tank. I need to add some unions there anyway, for when I put in a small bathroom at the shop (water storage tank is just behind my shop). In fact, that'll allow me to have water pressure near the storage tank for a hose bib, or that bathroom (since the line will be pressurized all the way from the basement). If that works... it's a win/win. If it doesn't, I'll go to step 2.

Step 2 will be to either do a DIY Arrestor, or thermal expansion tank at/near the pump. If neither of those work... I'll be pulling out what hair I have, and allowing some water hammer until I take some yoga classes, or meditate!!!! hahaha

 

[Reach4]

But, I'd honestly need a clear pipe as that's a moving target to attain perfectly. Especially if my water pressure is not constant, which I noted it's 40-60psi

Click inbox.

 

[LLigetfa]

A DIY arrestor would waterlog unless frequently aired up. You can buy arrestors that have precharged sealed cylinders.

 

[Reach4]

A DIY arrestor would waterlog unless frequently aired up. You can buy arrestors that have precharged sealed cylinders.

I wonder. Imagine how cool a clear one with a Schrader valve would be. You could actually see what would have become water hammer.

A 2 inch pipe would give 78% more capacity for a given length.

 

[JohnnyAirtime]

A DIY arrestor would waterlog unless frequently aired up. You can buy arrestors that have precharged sealed cylinders.

Pre-charged arrestors... are you speaking of the small 3/4" threaded size? About 6" long? ...like a sioux chief brand?

If so, you think they'd be big enough to work, if adapted to an 1-1/4" supply line, off a reducing T with reducers to adapt to 3/4" ??

 

[JohnnyAirtime]

I wonder. Imagine how cool a clear one with a Schrader valve would be. You could actually see what would have become water hammer.

A 2 inch pipe would give 78% more capacity for a given length.

As of now... If I can get a DIY Arrestor to work in white PVC, then I'd move to clear for the cool factor, and to see that it's not water logged (not working for me). Otherwise, it gets pretty costly for the "cool" factor at about $100 with fittings and pipe. Surely not going that route first run at it.

 

[LLigetfa]

Pre-charged arrestors... are you speaking of the small 3/4" threaded size? About 6" long? ...like a sioux chief brand?

As a test, I would try it in the priming port on the pump and not cut up the piping.

 

[JohnnyAirtime]

Okie dokie folks....

I did test #2... removed the check valve that was within' 4ft of the jet pump (booster), and installed a check valve up stream, at my water storage tank. As I mentioned, about 150-200 ft away from the jet pump.

Once all installed, I now do NOT get anymore water hammer at pump "off".
I also, don't get anything at pump "on" either.... so, that's a great thing.

Not sure where I read to put the check valve closer to the actual water supply, but... it worked.

The good and the bad is; Now all my lines that spur off the water supply are pressurized (before it was only tank head pressure). Nice for using a hose to spigot, or my RV hookups but no good if there's a weak glue joint. Hoping to not find any!!

I do get a small water rush, or maybe a vacuum or air noise at the pump when it turns off. But it's minimal. I won't be worrying about that, in hopes I've solved my hammer issue and won't be busting pipes apart.

... thanks for the advice you all gave. I was looking for more reassurance, and first hand knowledge. It looks like my issue is rare, as I've only read about one or two other issues like mine.

Good day!

(pictures below to show how it is now, with no-more-water-hammer!)

The basement setup; Where the union is up top, used to be where my check valve was;


Here's my outside water storage tank, and now new plumbing with check valve
(galv pipe is the neighbor's feed off the tank, PVC is my feed)


Closeup of my newly plumbed in check valve.

 

[Reach4]

A pressure gauge a little after the check valve would have been interesting. I wonder if there is a pressure drop below zero when the water shuts off.

I was surprised to see new galvanized. Polyethylene pipe is nice.

 

[LLigetfa]

The good and the bad is; Now all my lines that spur off the water supply are pressurized (before it was only tank head pressure). Nice for using a hose to spigot, or my RV hookups...

When the pump runs, there may be some suction on the line so the pressure is only while the pump is off.

 

[JohnnyAirtime]

A pressure gauge a little after the check valve would have been interesting. I wonder if there is a pressure drop below zero when the water shuts off.

I was surprised to see new galvanized. Polyethylene pipe is nice.

Don't know... but ya, it'd be interesting. Something I can screw into my 1/2" port my spigot is screwed into if I ever choose to do so.

The galvy was the neighbors choice for his water. Not sure why, other then he used to be a pipe fitter and it was easy for him to install. Should last his and my lifetime put together. Out here, my PVC will need replacing before his Galv pipe. Sun is strong, and PVC becomes so brittle with little to no UV protection.

 

[Reach4]

Out here, my PVC will need replacing before his Galv pipe. Sun is strong, and PVC becomes so brittle with little to no UV protection.

Good point. You need to paint your PVC, or otherwise protect it from UV. Maybe paint most of it, and tape black plastic (or just use black electrical tape)over the unions. Scotch Super 88 would be extra good stuff.

 

[JohnnyAirtime]

When the pump runs, there may be some suction on the line so the pressure is only while the pump is off.

I'm sure there's a tad bit of suction... as, the pump can pull water from a shallow well. My 1.5" line, is only gravity feeding along with the tank's head pressure. I'm betting the pump can draw more then the tank can supply. It's not a closed system, but acts similar in a way until a toilet flushes or faucet opened up. I don't know... I'm not a plumber, but just thinking out loud.

... I'm hoping the pressure (in the supply line) will work to my benefit. Because my shop's future bathroom (toilet and sink) can now be plumbed after the check valve, and still have pressure enough to fill a toilet or wash my hands. Kind of cool, since it's not AFTER the booster pump or pressure tank, and I don't have to run a line ALL THE WAY out to the shop. I know it'll make my pump run a bit more then normal, but I've got a backup. Not too worried.

 

[JohnnyAirtime]

Don't know... but ya, it'd be interesting. Something I can screw into my 1/2" port my spigot is screwed into if I ever choose to do so.

The galvy was the neighbors choice for his water. Not sure why, other then he used to be a pipe fitter and it was easy for him to install. Should last his and my lifetime put together. Out here, my PVC will need replacing before his Galv pipe. Sun is strong, and PVC becomes so brittle with little to no UV protection.

I'll eventually build a small wood frame, and cover it in hardi board.

The storage tank has been there for ... uhmm, guessing 10yrs or more. And it's 4" line (that supplies a stand pipe) and adapts to our 2" line (for emergency water or in case of fire) is all PVC. It's in pretty good shape, but I'll be covering it all as well too. Only exposing the valves and connection points. I hate to see it baking in the wonderful Southern California Sun.