pump cycles on...we get water hammer...suggestions??

[stp919]

When our pump cycles on, we get a water hammer effect close to the area of the pressure tank. I would appreciate any suggestions in how to diagnose the problem. The pressure tank is relatively new; I replaced it about a year ago. We have a water softener system in place; resin, carbon, brine tanks as well as a 200 gal "chlorine contact" tank. The system as about 3 years old and has been functioning fine. We do have quite an old water heater; probably about 20 years old and it does not have a relief tank installed on it. I given you all the information that I think of of the top of my head, thats why I need your help. The water hammer is a symptom that I need to find the cause of. thanks for any help. Steve.

[valveman]

You probably have an extra check valve before the pressure tank. Remove the extra check valve and the water hammer should go away.

[stp919]

Thanks for the post. We have a check valve at the well head and also I noticed one on the line leading to the conditioner, past the bypass; there's no others that I can see. This setup has been working fine for several years but has recently developed the hammering. Anything else I should look for? Thanks again.

[valveman]

Do you have a submersible pump?

[stp919]

Yes, although I can't give you any specs since there isn't an id tag on it.

[Rancher]

The submersible pump contains the only check valve that you really need in your system.

Rancher

[stp919]

So do you think that I should start by removing the check valves? I guess the one in line with the softener would be the easier of the two to remove. Why would it now be causing a problem after all this time? Any other things I should be looking to? Thanks again.

[sammyhydro11]

I get a lot of calls about water hammer and most of the time its a bad valve in the toilet.

Sammy

[Raucina]

Perhaps what you call hammer is actually a bad precharge in your pressure tank, or no charge if its a plain tank. Describe exactly what you mean by hammer - multiple "hits" ? momentary loss of pressure? If it all worked for several years I would'nt start tearing out valves now.

[stp919]

Trouble is that we only get it when the pump cycles on and in the garage where the pressure tank and softener system is located. We get nothing when any other faucets are open. I think I'll try to drain the whole system down to see if maybe there are other air chambers that might be waterlogged.

[stp919]

responding to Raucina:

The pressure tank is preloaded to 38psi, cut in on the pressure switch is 40psi so no problem there. When the switch cuts in, there may be about a 1/2 to 1 second span before we'll get one good "slam". I get no loss of pressure. Like I mentioned in the previous post, I think I'll drain everything, refill and see what happens.

[Raucina]

So you have 3 check valves. One on the pump, one at the well head and one at the conditioner. Perhaps the check valve at the pump is leaking and your slam is the pressure differential between the pump and the one at the well head. You have some detective work to do. If you had a pressure gauge on the pump side of the well head check valve you would know quick if that were so.. Also do not count on your pressure gauge and your tire pressure gauge to be at all accurate. I have a few tire gauges that vary 8psi and more.

[stp919]

I appreciate all the help. At least it gets me started in a direction. Also I didn't mean to confuse anyone when mentioned "wellhead" and "pump" which I, being a novice, used to identify my deep well submersible pump. I'll post again after I do some checkin'. Thanks again.

[speedbump]

I agree with Valveman and Rancher. Remove the check valves and the hammer will go away.

bob...