Puzzled

[Ray]

Not sure whether I need to worry or not . . . .

 

We've had the boat for 2½ years now and have spent a lot of time on it as we've gradually fitted it out. We've also had a couple of two plus weeks cruises.

 

The other week, following advice on here, I checked the accumulator pressure and had to top it up a bit - I think I only gave it a couple of pumps when we fitted it it several months ago.

 

On two separate occasions over several visits since we increased the pressure and when we've been sitting and either reading or watching television, the pump has cut in for a few seconds (as if we were running water, which we weren't because we was sat down).

 

There is no non return valve on the supply to the calorifier and all other cold water goes direct to taps or the toilet.

 

Is the pump cutting in because of a change in pressure in the calorifier as the water cools, or could we have a leak? Which is the most likely? We never experienced the problem before we increased the accumulator pressure.

[denboy]

chances are there`s a leak if it cuts in regular

[casper ghost]

My Dad's pump did the same, it turned out to be a slow dripping tap. Or as already suggested a slow dripping leak somewhere.

[Ray]

Thought about both. Can't find a tap that leaks although it could be the loo which isn't so easy to notice. The kitchen tap does, occasionally, dribble for a second for no apparent reason. maybe that's the reason.

 

Not sure about the leak as nothing's changed since we installed the system, about 18 months ago, except that we've increased the pressure on the accumulator. Would this introduce a leak - we've all plastic plumbing?

[Les Taylor]

We have the same symptoms with our water pump, it cuts in for maybe 2 or 3 clicks every couple of hours or so.

I have checked thouroughly for leaks and can't find any, I guess it could be the valve in the pump which is not holding pressure 100%.

I can put up a few clicks every couple of hours.

 

Les

[Ray]

Mine cuts in unexpectedly once every couple of weeks.

 

I don't have a problem with it doing that, I'd just like to know why it does it and why it has only done it since we increased the accumulator pressure.

[Keeping Up]

Ours always cuts in just the once, about an hour or two after we've stopped the engine, to take up the contraction as the system cools down a bit

[chris w]

Mine cuts in unexpectedly once every couple of weeks.

 

I don't have a problem with it doing that, I'd just like to know why it does it and why it has only done it since we increased the accumulator pressure.

I think it's just a coincidence that it has appeared to do this since pumping up the accumulator pressure. When the pump has switched itself off, the pressure in the accumulator is the pump's cut-off pressure (usually about 30psi) and not the inherent pressure of the accumulator set by you.

 

To what pressure have you set the accumulator and did you set it with the pump turned off at the fusebox and a tap open to drain the accumulator? Any other way will give a false reading. You need to set it to around 12-15psi.

 

The only things that will cause your pump to run occasionally are a leak from the system (tap or pipe or joint) or the built-in non-return valve inside the water pump misbehaving...........................unless you have eroneously pumped up the accumulator to some really high value.

 

Chris

[Ray]

Chris

 

I didn't check it over the weekend but I only upped the pressure a few weeks ago and I'm sure that I set it at 15psi as suggested by your good self some while back.

 

I turned the water pump off, opened a tap and when the water stopped flowing, measure the pressure with a tyre gauge. It was very low so I pumpmped it up to (I'm certain) about 15psi. I'll check again over the weekend.

 

One other thing that I've noticed recently, which may be connected - excuse the pun. We open a tap and water runs. The flow slowly decreases and then the pump cuts in again and the flow increases. The pump stopsa dn th cycle repeats until we stop running the water.

 

I thought that the accumulator was designed to stop this. Does this indicate that I have got something wrong with the way I've set things up?