Messages

1

Pumps, Wells, Tanks, Controls / Re: Water Hammer on Pump Shut off

« on: September 11, 2013, 07:24:06 PM »

So I finally got around to installing a CSV1W on my system.  I'm happy to say that my water hammer is almost entirely gone, but only if I set the valve so the pump runs for about 3 minutes to fill the tank after it turns on (40/60 pressure switch) instead of the 2 minutes recommended in the installation directions.  I'm not sure why this is but it seems like it takes that long for the water flow to really slow down.  It doesn't seem to be a problem though.

I do have one question however.  The instructions say to set the tank pressure to 5 - 10 psi below the cut-in pressure for an above ground installation.  I left mine at 2 psi below and everything seems to be working fine.  Why do you recommend setting the pressure so much lower and should I do this even if I have no problems at the current 38 psi?

Thanks again and I highly recommend your product!

2

Pumps, Wells, Tanks, Controls / Re: Water Hammer on Pump Shut off

« on: July 11, 2013, 07:35:21 PM »

Thanks for the explanation, I'm going to order one and give it a try.  May take a while before I can install it but I'll post back on the results once it's up and running. 

3

Pumps, Wells, Tanks, Controls / Re: Water Hammer on Pump Shut off

« on: July 11, 2013, 09:24:01 AM »

Hello Cary,

Thanks for the feedback.  Actually replying the next day is very fast in my opinion since I'm sure you are busy.  So just a couple more quick questions based on your response.

If my check valve is sticking then installing the CSV may result in the valve not completely closing because I will no longer have the high velocity of the water column reversing to slam it shut like i do now on pump shut off (soft stop with CSV I suppose)?  The telltale sign of this then would possibly be a slow loss of pressure in the pressure tank if the valve is indeed leaking?

Your comment on the pump drawing less amps at low flow is a little confusing to me.  I'm a mechanical engineer so maybe just not enough electrical experience but at low flow (CSV almost closed and keeping pressure at pre-set pressure) isn't the pump pushing less water at higher pressure and therefore working harder?  More work per a given period of time means more power and therefore more heat generated?  Does the pump actually slow down (less rpm's) with higher pressure and less flow as opposed to full flow at lower pressure?

Thanks again.

4

Pumps, Wells, Tanks, Controls / Water Hammer on Pump Shut off

« on: July 10, 2013, 11:19:33 AM »

Hello,

I have a residential well that experiences water hammer every time the pump stops (since I've lived there so not a new problem).  The well is 90' deep, the casing is 5" and the pump is a 3/4 hp 10 gpm Sta-Rite HS+ Signature 2000 4" submersible at 70' and run by a 40/60 pressure switch.  I replaced the pressure tank 5 years ago with a 52 gallon which has 14 gallon draw down at 40/60.  I timed the fill time and it takes about 1.2 minutes with nothing running.  I don't know if there are additional check valves to the one on the pump.  The supply line is 1" PVC that enters the basement, immediately travels up the wall, crosses about 12 feet under the floor joists and then down to the pressure tank tee in the furnace room.  The system feeds a 2000 sq ft house with 2 full baths and also occasional lawn watering.

I'm thinking about adding a CSV1W for the constant pressure and less pump cycling benefits and I believe this will also solve the water hammering but I'm wondering if this might just be a bandaid for the hammering issue.  I assume the water hammer occurs from the check valve slamming shut.  Is this indicative of a bad or worn out check valve?  I'm worried that if the valve is bad that the pump may get damaged at some point.  Could this just be a normal result of the water column slamming back against the check valve?  I don't lose any pressure so I'm pretty sure that the check valve doesn't leak.

Also I understand the concept and the benefits of the CSV but I do have a concern about the pump overheating at low flow rates.  I don't know if the pump has the recommended flow inducer and I'm not inclined to pull the pump and install one for obvious reasons.  I understand that the CSV pressure and the shut off pressure should be adjusted to keep the tank fill time under a couple minutes after water demand is stopped so I'm not concerned there.  I'm more concerned if a single faucet is left running for an extended period, during long showers say at 2 gpm or lawn watering at low rates.  Will this provide sufficient cooling if there is no flow inducer at the pump?  Do most pumps have a thermal protection shutoff if they start to overheat?

One additional question on the installation of the CSV1W.  Your information sheet talks about not having the pressure gauge and switch on the main supply line however most pressure tank tees that you buy have the 1/2" ports for these on the straight run from the supply intake to the downstream exit of the tee (not on the 12" pipe to the pressure tank) which is how my system is currently set up.  The install would be much easier If I could leave this as is and then I only need to plumb the CSV in at where the PVC feed line ends and the tank tee starts.

Thanks in advance for your help!