How often should fresh water pump kick in with no demand

[Saqqara]

This is my first boat with real plumbing... Surveyor said the pump was on its last legs because it would kick in from time to time with no demand. I replaced the pump (for other reasons), and it still kicks in from time to time. I have checked all the connections and remedied one small leak but have not found any more. It still kicks in every six or seven minutes or so briefly. There is no accumulator. I typically just leave the pump switched off between uses.

Is this normal? Or is there almost certainly a leak somewhere?

[shorebird]

Sometimes its just a slight drip at a faucet, but could easily be a leak somewhere in the system.

[nigel1]

Could be worn valve seals on the pump.
What type of pump, most you can get an overhaul kit at a reasonable price.

[zeehag]

i found when mine does that, i just turn it off--has worked that way for 5 yrs so far--so good.. i have 2 spares for this use. found my spares at marine swap meet in la cruz de huanacaxtle.....

[Paul Elliott]

The pump shouldn't kick in at all. If you have no leaks, the pump itself probably has an internal leak in the valve seals. This isn't dangerous or anything -- more of a minor nuisance -- but it may be time to repair or replace the pump.

[Cheechako]

usually a sign that there is a small drip, not a bad pump. Could be as little as one drop per minute type of thing. Possible internal pump issue though I spose...

[svmariane]

Originally Posted by Saqqara

This is my first boat with real plumbing... Surveyor said the pump was on its last legs because it would kick in from time to time with no demand. I replaced the pump (for other reasons), and it still kicks in from time to time. I have checked all the connections and remedied one small leak but have not found any more. It still kicks in every six or seven minutes or so briefly. There is no accumulator. I typically just leave the pump switched off between uses.

Is this normal? Or is there almost certainly a leak somewhere?

Not normal - there is a leak somewhere. It might be small and not even drip water that you'd notice, but it's there somewhere.

You already replaced the pump (hope you kept it for spare parts).

You've already checked each connection, right? Re-did them all with teflon tape, right?

So it's gotta be one of the faucet/outlets or a pinhole in one of the installed tubing pieces, right?

What I did that worked: disconnect all the plumbing from the outlet side of the pump.
Attach a piece of spare tubing or garden hose from the pump to one outlet. Test. Repeat for each outlet.

If all outlets (faucets, or whatnot) are good...

Attach one piece of original tubing to one outlet. Test. Repeat.

Theory is to break down the system into small sections for testing.

Good luck!

James

[Saqqara]

I have replaced the pump with a brand new Flowjet pump this morning, and it still kicks in occasionally, that's why I'm asking. I timed it and it's actually silent over 15 minutes, then a brief bump of one to three seconds. I checked at the sinks and the pump and the hot water tank and corrected one small leak earlier today, which means I need to check the whole length of the lines I suppose.

I just figured before I did that, I'd ask if it was normal for it to cycle from time to time. I don't like to chase my tail.

[roverhi]

On my old boat with the old style Jabsco Diaphragm pump, the pump almost never cycled. On my current old boat, have a rotary pump and it cycles quite often, maybe every 15 minutes or so. Checked the entire system and could find no leaks, replaced a couple of hose connections because they looked iffy but it still cycled. Thought it was the pump so replaced it with a similar pump, still cycled. Think the problem may be with the rotary type pump. I just turn off the pump which is convenient as I can reach the circuit breaker from the galley. Mostly use the foot pumps in any case. Pressure system is BIG water waster.

[senormechanico]

My pressure pump NEVER does that EXCEPT after a long motor.
When the hot water tank cools, the water contracts and the pump repressurises the small accumulator tank. It happens twice before the hot water is cooled to ambient temp.

[Stu Jackson]

The pump shouldn't cycle. There IS a leak somewhere. Some of us have combated the work requird to find the leak by turning the pump off. Been there, done that.

You've replaced the pump and it still burps every 15 minutes.

There's a leak somewhere.

Either learn to live with it, turn the pump off, or find the leak.

Them's yer options.

[boatman61]

Try bleeding the air out of the tank...

[ErikFinn]

Mine does that after I've run the tanks dry (accidentally) and topped off. Then I find air in the water filter, bleed it, and its ok.

[nigel1]

Like James says, need to test each individual run of water pipe from where it branches off from the pump discharge, to the tap/faucet.
One likely culprit, if fitted, is the deck shower

[kentobin]

I agree with everyone else who feels you have a leak somewhere or your pump won't cycle. I eventually found very slow leak on a fitting at the water manifold.

Until you find it I also agree with the poster who recommended you turn off the pump when you're not using it or leave the boat. Water damage from hatch leaks is maddening enough.