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Al S
Very Low Water Pressure

Our home is on a well (110 feet deep). Since moving in to our 2500 SF, 1975 ranch home on a 1/2 acre lot 1 year ago, we have noticed the water pressure at all facuets particularly the outside bibes is very low. To give you an example, if I put a hose on a outside bib (located about 25 feet from the incoming water supply) the water spurts out about 5 feet with the bib fully open. If I put a hose on the far most bib from the water supply (about 60 feet) with an oscillating sprinkler, the spinkler will throw water about 5 feet Our neigbors who are also on wells do not have any problems. (Most of these homes are two story Colonials built around 1975.) We have had two well companies and two plumbersin and we've gotten 4 different answers - change out the 1/3 HP ,7 gal / min well pump to a 1/2 HP pump, dig a new well, increase the size of the pressure tank,and replace the main copper lines from 1/2' to 3/4" (about 80 feet) plus disconnect the whole house water filter. The tank pressure is at 60 psi and the pump comes on when it drops to 45 psi and is back up in several seconds. I have disconnected the water filter and there is no noticable change in pressure at the facuets. We are at wits ends! Has anyone experienced a similar problem and found a solution?

Re: Very Low Water Pressure

It sounds like it is the filter that is causing the problem. Are you saying that you have good pressure at one hose bib but not the other? If so I'm willing to bet that one is before the filter. A picture of just how you removed the filter would help.


Re: Very Low Water Pressure

A 7 GPM pump is only good for a one bath home with no washer so clearly your pump is undersized for your house but the problem of no pressure at the hose end is a function of too small of a supply line. A standard main supply line in any house is 3/4 inch. The individual lines that run off of the 3/4 inch lines would serve the lavatory, WC, bath, kitchen, bibs laundry etc would be 1/2 inch. There is something called "friction loss" in any water line and in small lines like 1/2 inch it is huge especially in long runs. Fire depts routinely do friction loss calculations to determine what kind of gpm they will have at the end of their hose lines. You can do your own friction loss calculations - look up the formula on line or get a book from the library. Clearly you need to upsize to a 3/4 inch main supply line and you will be amazed at the difference in gpm.

Re: Very Low Water Pressure

Unless you are running out of water you shouldn't need a new well.

Increasing the size of the pressure tank would only add more time before the pump kicks on, it won't increase pressure.

Open a bib and watch the pressure gage, if the pump kicks on at 45 lbs and maintains that pressure then the pump is supplying enough water and pressure, although it is to small a pump for your whole house.

The loss of pressure at the bibs is because of restriction, the main copper lines should be 3/4/ ", the whole house filter can be another cause and turning it to bypass may not help. Water softeners, reducer couplings, and shut offs can also reduce pressure.
A faulty check valve could also be a problem.

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