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AlfredNisky
Jan 26, 2009, 02:13 PM
Hello,

I recently moved into a newly constructed home. I have a grinding pump in the basement and when it cycles off, it makes a loud clunk that vibrates through the house. The plumber says its normal and that he could put some insulation around the pipes to reduce the vibration but not the clunking. Is it normal for a grinding pump to operate loudly when finishing its cycle?

Also, we had an issue when turning on the bathtub faucets, the shower heads would run as well. It happened in all of the bathrooms with bathtubs. The plumber indicated that the water pressure in the house was too high and he installed a pressure valve to reduce the pressure. Since he has installed it however, we hear a loud humming from the valve when we run water (i.e. toilet flush, or even running water through the refrigerator). Is the valve defective? Was it the right solution to begin with? Every now and then the water still comes out of the shower when the bathtub faucet is running.

Thanks for your assistance

massplumber2008
Jan 26, 2009, 05:52 PM
Hi Alfred...

I'm betting that the noise you hear is a check valve closing at the end of the pump cycle. Here, check valves are installed to prevent any pumped sewage from falling back down the pipe which could create a short cycling effect on the pump if not prevented... so they are required to be there and they are pretty famous for making these clunking noises.

In my experience the following helped to fix this clunking... most of the time:

Install check valve higher up up than it is now (less water to close flapper)
Change check valve to different kind of check valve.
Hang pipes super well... above and below the check valve to help with pipes shaking.

I am a big fan of the PVC compression check valve (pic.#1) and have had very good success with these over the cast body type check valves (pic. #2). Wonder which type you have. Both are code legal here.

Finally, it sounds like the contractor did his job (unless pipes shake or are hung improperly) so if you consider asking the contractor to move the check valve higher or to change out the cast model of check valve to the compression type please expect that you should pay him for his time as he probably has an installation manual that he followed to the letter and that makes him right! The installation manual, however, will not always know best!!

Let me know if you have more questions or let me know if I entirely missed this.

MARK

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AlfredNisky
Jan 26, 2009, 06:07 PM
It will probably be worth the cost to reduce the banging; thanks for the info.

Any assist with the water pressure valve that is reducing water pressure? It is probably the most annoying now. When it starts humming it can wake up the house.

massplumber2008
Jan 26, 2009, 06:14 PM
Hi Alfred...

It would be interesting to know what pressure you are set at now and what your pressure was before the pressure reducing valve (PRV) was installed..?

You can purchase a simple pressure gauge that you can hook to your outside faucet at Home depot, Lowe's or Menards home supply stores... see picture below. It costs about $10.00.

Otherwise, the PRV should not make too much noise unless sediment is restrictng flow or similar issue.. Last thought here is that the STRAINER of the PRV could be clogged... see 2nd picture. May be a good idea to clean the filter of sediment, purge the line without the filter in place, replace the filter and see if that improves things?

Let me know what you think. Sorry not easy answer here!

MARK

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AlfredNisky
Jan 26, 2009, 07:12 PM
Thanks Mark once again. I will have to wait until warmer weather I'd imagine to run and check the pressure outside (upstate NY). Could high pressure (city pressure) blow past faucet fixtures and go to a shower head?

I also see where the check valve is installed. It is right above the lid to the "well". Seems kind of low per your instructions, so I will ask for a better pipe hanging job and to raise the valve closer to the ceiling of the utility room (about 6' to 7' higher).

It's a new house so all of this is going on the punch list :D