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keith777
Dec 30, 2009, 10:08 AM
First, this seems like a great forum with helpful folks and I look forward to contributing as well. I have been trying to troubleshoot lots of leaking faucets, which I think is caused by too much pressure at times.

The house is about 6 years old in Florida, on a well. There is about 150 feet of 3/4 in pvc connecting the galvanized tank to the house. My well pressure switch seems to work fine, cuts in at 30 and off at 50. I attached a pressure gauge to the outside spigot on the house and it reads about 45-50 when the tank at the well reads about 50, so pressure stays consistent between house and well. I have tested turning on and off faucets inside the house and when I do a few, I go back outside and can see that the pressure at the spigot has jumped up to 70 psi or more by reading the needle that measures highest pressure. I also attached the gauge to a spigot right after the tank, before the water comes through the house, and I don't ever get the surge in water pressure there. The surge in water pressure comes only after water goes through the house.

I'm not sure if I need a regulator or not, since it seems that water out of the well tank does not exceed 50, and wouldn't know where to put one since it seems the house plumbing causes the pressure increase. I looked at a pressure relief valve at Lowe's but from the packaging it looked like it only relieved very high pressure increases, not the 70 of so that I get. Is the 70 psi causing my leaks, or something altogether? Any ideas and thanks so much!

jlisenbe
Dec 30, 2009, 11:09 AM
1. You would not want a pressure relief valve. You might be interested in a pressure regulator such as is linked below.

Valves | Water Control | 3/4" Water Pressure Reducing Valve | B170312 - GlobalIndustrial.com (http://www.globalindustrial.com/p/plumbing/valves/water-control/3-4-water-pressure-reducing-valve)

2. As to the why of the surge, that is strange. I will venture a guess. You mentioned a galvanized tank, which means you probably do not have a bladder tank. If that is the case, then your well system probably replinishes the air in the tank as follows. When the pump cuts on, the wellpipe is filled with air which is pumped into your pressure tank. The tank has a valve on the side, about halfway up, which bleeds off excess air so the tank does not fill with air. If you have a lot of wellpipe, I could see the pressure spiking some when the pump cuts on as this air is pumped into the tank, and before it can be bled off. You might want to watch your pressure gauge as the pump cuts on and see if you notice a spike occurring at that time.

keith777
Dec 30, 2009, 09:03 PM
Thanks - I will probably try that. I assume I can dig a hole and put that on inside a valve box, right?

KISS
Dec 30, 2009, 09:13 PM
I'm not thinking that way. I'll bet the 70 psi is due to water hammer. When you shut off a valve suddenly, you will get an LARGE increase in pressure.

Usually around the house or at the main inlet, there may be "stupid looking pipes" that look out of place. Maybe one 30" high, verticle, going no where with a cap on t.

The is a poor man's water hammer arrester. It's an air column. It absorbs the force of the turned off water.

Hopefullythese exist. Sometimes they are in the wall near toilets.

Here are some commercial products: PlumbingSupply.com - Water Hammer Arresters (Arrestors) (http://www.plumbingsupply.com/waterhammerarresters.html)

Before you do anything. Turn off the water and drain the house plumbing and refill it. This should recharge the air chambers.

keith777
Dec 31, 2009, 08:01 AM
Thank you - that sounds more like it for my situation. I will try draining the plumbing and see. Thanks again!