Loss of water pressure

Sep 1, 2021 By The Clozer

LOSS OF WATER PRESSURE from faucets, etc.

1         the #1 cause of low water pressure is a plugged screen (aerator) at faucet outlet.  Unscrew the aerator, clean and replace.

2         There may be other screens or orifices located in most newer faucets such as in a hose feeding pull-out sprayers or where supply hoses connect to valves under the cabinets.  Try running Hot & Cold separately to determine if it's one or the other or both.  If it's both then it should be a common screen shared by Hot & Cold.

3         A slow filling washing machine may be a result of plugged screens in the back of the washing machined where the hoses connect.

4         A slow filling toilet tank may be the result of a plugged screen located where the supply line connects under the toilet tank to the fill valve or ballcock valve.  Not all ballcock valves have screens, so slow filling may be a result of a plugged ballcock valve in the toilet tank.  Take apart and clean debris or replace.

5         If you turn the faucet on and pressure is good, but dies off usually quickly and you have a filter system, it is most likely the filter cartridge that needs replacing.

6         Constant low pressure could also be a result of;

  1. water leak in system (underground or under Bunkie, etc.)
  2. May be a result of a plugged or partially plugged steel or galvanized fitting located in the system.  Common places for these fittings are at the pressure tank or pump.  It is also possible that these fittings could be located underground depending on pipe routing

7         To determine if you have a leak or plugged fitting you can use your water pressure to test the line.  Simply use your existing pump to charge the system as it normally would until pump shuts off.  Close the valve on the cottage side of pressure tank to isolate that side of system.  Check the pressure gauge on the pressure tank or pump (jet pump) to determine that pressure is holding, which if holding will tell you that pressure is not escaping down the line to your water source (Lake, river, well, etc.) thru the foot valve or submersible pump. 

If all is good on the water source side of pressure tank, proceed to open the valve on the cottage side of the pressure tank.

If pressure drops, then there is an issue on the cottage side of the pressure tank. 

Note:  Be sure no one is using any water during pressure test

If pressure drops right off to zero, recharge system a couple of times with the valve closed and try opening the valve again.  If it keeps dropping to zero after a few minutes then there is most likely an undetected leak in the system.  Be sure that a toilet tank is not "running on" undetected.

If during the testing process, the pressure does not drop to zero, but looses considerable pressure, it may be a plugged filter or partially plugged galvanized fitting.  These two conditions cause a gradual reduction in pressure, but not complete loss of pressure normally.

A plugged filter or fitting allows pressure past it slowly until pressure equalizes on both sides of blockage.

Let's say your pressure settles out at 10 PSI, simply open the valve again to bring pressure back up in the system, cloze the valve to see if pressure settles out at a higher pressure than before and stabilizes.  If after doing this, two or three times, the pressure stabilizes at a higher pressure each time, there is probably not a leak but a restriction.

Galvanized or steel fittings can be the cause of many problems in a water system.

Galvanized fittings on the suction side of pump (or discharge side of submersible pump) can easily go undetected.  You might notice it's taking longer for system to come up to pressure, or a simple visual check of fittings may be required. 

Replacing galvanized fittings with brass fittings is recommended.