Check valve on pressure water system?

[geoleo]

I have a 42ft sailboat with 2heads . Have a shurflow 3.5gph pressure water pump with a separate 2qt tank. The pump goes off and on about every 20 minutes. There are no leaks. I believe the hoses swell over time and this makes the pressure drop as all the hose diameters are larger when pressurized over time. Could I help this by putting a inline poppet type brass check valve in line just downstream from the tank?? Thanks.

[lancelot9898]

I'm having a similar problem except mine is running a second of two every several hours. It's a shurflow pressure pump but no separate tank. No leaks, bilge is dry. I think that with time the pressure is reduced with some small backflow into the water tanks. Someone said that the pump should have a check valve built in and that makes sense since the pump did not do this when new. Or maybe a new pump impeller keeps the pump from losing pressure. Installing a check valve makes sense to me if that pump is not enough to stop the pressure loss.

[Steve Bean]

If the pump keeps on pumping again and again, where is the pressure going? It must be leaking somewhere unless the hoses are getting bigger and bigger.

[geoleo]

Originally Posted by Steve Bean

If the pump keeps on pumping again and again, where is the pressure going? It must be leaking somewhere unless the hoses are getting bigger and bigger.

I said I suspected that the hoses were swelling over time.

[a64pilot]

There is a Leak, very likely as has been said the pump itself if there is no leak in the boat.

[dlymn]

Check your accumulator. The valve on the top might be leaking. Can be dirt in the built in check valve in the pump. Pressure relief valve or drain cock on hot water service can also leak. The pipes can't be getting bigger and bigger all of the time. Leaks into a wet bilge can be very difficult to find. Sprinkle talcum powder near suspect joints. Water trail will become obvious

[geoleo]

bilge is always totally dry

[rwidman]

Originally Posted by Steve Bean

If the pump keeps on pumping again and again, where is the pressure going? It must be leaking somewhere unless the hoses are getting bigger and bigger.

There is a built in check valve in the pump. This can leak and the pressurized water on the pressure side of the pump leaks back into the unpressurized supply.

You can install a separate check valve as close to the pump as practical, rebuild the pump or replace the pump.

[StuM]

Originally Posted by geoleo

I said I suspected that the hoses were swelling over time.

If this were the cause and the pump is running every 20 minutes, your hoses would look like those balloons that they make animals out of by now.


If you are certain that there are no water leaks after the pump, there must be backflow in the pump.

[StuM]

Originally Posted by geoleo

bilge is always totally dry

Have you checked for any dripping faucets in heads or galley?

[dlymn]

Is the shower bilge dry? A leaking joint in this area just looks like a bit of shower water left over. can you access every bilge compartment?

[Mycroft]

To test for a bad pump check valve, just connect a short piece of hose to the pump and see if it holds pressure. If it does, then you have a leak somewhere. My most recent leak was a bad seal in the hot water heater.

[topmast]

Most little pumps hold the pressure internally,Rubber flopper reed valve or poppet They get hard or turned out of original position bit or a bit of crud or hair gets caught and voila a bit of seep back to tank side. The pressure slowly falls back and pump starts up again.

[crabcake]

[Cadence]

Is the 2qt tank designed to be an expansion tank and has no air in it?