Low Water Pressure

[carmicfg]

My daughter is buying a house, she said the water pressure is low.

The house was built in 1950 and it has a well. From what I understand the well pump is fairly new. It has three baths, she said one tub/shower has good pressure. The rest of the house is low.

Could old galvinized piping cause this?

The current owner told her that they were told that low pressure, water saving valves from California were installed in the house...yea, right!

An inspector is coming today and I will be there. Any suggestions on questions for the owner or inspector to get to the bottom of this?

Thank you

[carmicfg]

Will be leaving in about an hour to meet Inspector...Anybody have any suggestions?

[HayZee518]

electrolysis occurs any time there is a mix of active metal piping. galvanized and copper make up a battery at their junctions. galvanized piping that contain water with a high alkaline content will build up an internal scale that may clog the pipes. suggestion when you replace pipes: use pex. it isn't affected by scale or lime. it isn't "electrically" active. it can be "fished" through walls like electrical wires. have the inspector check the storage tank. the bladder inside may be broke. normal pressure from a well is 45-55 psi.

[carmicfg]

Thank you for the reply HayZee!

I actually left before I saw your suggestions. The storage tank is fairly new, he said it was distributing 1.5 gallons/min. I spoke to the neighbor, he said his well dried up 10 years ago.

The pump was located in the basement, it was not a submergable. The owner said the well was somewhere behind the garage. The Inspector could not locate it or find a stack.

[HayZee518]

since the well pump is not a submersible I would think that the well is a cistern that collects ground water or seapage from a nearby stream. a dug well gets water from in between the rock layers of the ledge. the pump will probably be an "ejector pump."

[Redwood]

Normal pressure for a well is determined by what the pump can maintain and the settings of the pressure switch for the shut off pressure and differential pressure. Typically the pressure switches come set at 20/40, 30/50, and 40/60 with the 30/50 probably being the most common. A 30/50 switch would turn on when the pressure drops to 30-psi. and turn off when it reaches 50-psi. The differential is 20-psi which is the pressure where the pump is running after turning on at the low pressure. If a pump cannot physically reach a pressure of say 60-psi the pump would turn on then run continuously and never shut off, which would eventually destroy the pump.

There are 2 different pumps that would be used in your application either for a shallow well or, a deep well but neither would be an ejector pump. The shallow well pump will have a single inlet pipe and that limits it's ability to "lift" water. The pump for a deeper well would be known as a "jet pump" and would have 2 lines attached to it from the well. One of the lines attach to the inlet and the other actually sends water under pressure to the bottom of the well where a water jet is placed in the center of the suction line to aid in "Lifting" the water greatly increasing the depth from which water can be pumped.

Shallow wells can be susceptible to contamination from surface water.

The pressure tank should be pressurized to 2-psi lower than the pressure at which the pump turns on with the pump off and a faucet on with the pressure released. Hopefully you have a bladder type tank which is typically indicated by a painted steel or fiberglass tank with a valve on the top of the tank. If the tank is constructed from galvanized steel and a connection on the side of the tank it is probably not a bladder style tank. Improper air pressure in the tank is usually indicated by "short cycling" of the pump where the pump turns on virtually every time a faucet is turned on and can cause a pump to die quickly.

If you have any doubts on the well pump system working properly I would advise having a company that services well pumps take a look at the system to see what if anything is wrong with it and give you an estimate for repairs to go back to the seller with to negotiate a resolution. The money you end up paying for the diagnostic charge by an expert would be money well spent in the event you actually need a deeper well drilled which can cost serious money. I would also make arrangements with the seller where they cover the diagnostic and or, if a small repair is needed the well pump repair guy can just go ahead with the repair. Sometimes repairs can be as simple as a new pressure switch or, punching rust out of the pipe nipple the pressure switch is attached with. If the repair is that simple the repair should just be done while he is there and save the cost of a second trip out.

[Speedbump]

The storage tank is fairly new, he said it was distributing 1.5 gallons/min.

Apparently he determined this by running a kitchen sink and measuring the flow there. That is not how to measure flow of a tank or pump.

You said your pressure was good in one faucet but bad in the rest. This indicates plugged up piping like you suggested. Having been built in 1950 almost guarantee's galvanized plumbing. On just about any well water, they have to be getting pretty badly plugged.

[Redwood]

I'll agree that if the pressure varies between faucets it probably is a distribution problem...