Water pressure again

[All_at_Sea]

I had a fault with my jabsco max par 2.9 fresh water pump so replaced with a new one and bought the spares for the old one to keep onboard. However since then l can not get the pressure accumulator to work, or pressure up?

Can someone take me through the process, something from memory of leaving taps on?? I have three outlets, sink and two heads.

 

[VicS]

I had a fault with my jabsco max par 2.9 fresh water pump so replaced with a new one and bought the spares for the old one to keep onboard. However since then l can not get the pressure accumulator to work, or pressure up?

Can someone take me through the process, something from memory of leaving taps on?? I have three outlets, sink and two heads.

Do'nt understand what you mean by "can not get the the pressure accumulator to work". It is a purely passive component, It is the pump which pressurizes the system.

However the link below may help. It explains the purpose of the accumulator and tells you how to adjust the gas pressure inside it to the correct value.

https://www.jabscoshop.com/files/Accumulator and Expansion Tank Instructions ZPWL4 doc595.pdf

 

[philwebb]

Hi All-at-sea, have you checked that there is air in the accumulator? If you can access it you should find it has a schrader valve on top (same as a car tyre) check the air pressure with a tyre pressure gauge. Halfords sell them, I like the one with the metal slide. The set pressure should be on a label on the side of the accumulator. If it is low pump it up with a bike pump. Re-check pressure. If you can’t pump it up the internal diaphragm has had it and it needs to be replaced.
When you have done this check your water tank is full and the valve is open. When you open the nearest tap the pump should start, if not check the 12volt connection. Check the strainer, has it got air in it? If so let the air out by loosening the cap. (Need a container underneath). Open the taps one at a time starting from the nearest to the pump to the furthest away.
Turn off when the water runs without air bubbles.

 

[All_at_Sea]

Does the accumulator get pressurised as the pump runs or is it completely separate? My taps start slowing up and only when a trickle does the pump kick in. Very annoying.

 

[VicS]

Does the accumulator get pressurised as the pump runs or is it completely separate? My taps start slowing up and only when a trickle does the pump kick in. Very annoying.

The accumulator should be pre- pressurised with air to 2-3 psi below the pump cut in pressure. The link in my post above and philwebb's post explain how to do this.

If the pump is not cutting in at its specified pressure ( 15psi) then you need to look at its pressure switch. It may be adjustable but it seems to be so far adrift from the correct cut in point that it is possibly defective and needs to be replaced.

See http://www.jabscoshop.com/marine/pu...-0292-par-max-29-pressure-controlled-pump.htm for the parts diagram and list
(£19 plus VAT)

At your leisure you may be able to dismantle and sort out the old switch assembly which you can then keep as a spare.

 

[coopec]

Does the accumulator get pressurised as the pump runs or is it completely separate? My taps start slowing up and only when a trickle does the pump kick in. Very annoying.

I'm sure Vic is referring to this text

At what pressure should I set the accumulator tank?
The pressure in the tank is adjusted by means of the air valve in the closed end.
The tank is supplied with an internal pressure of about 2.8 bar (35 psi) . Reduce this pressure to 2-3 psi below the cut-in pressure of the pump (refer to pump instructions for details) . This pressure adjustment is best done before installation of the tank, using a car-type pressure gauge to determine when the required pressure is reached, as follows:

i. Depress the central pin of the Schrader valve with your finger, to release gas

ii. Release gas a little at a time, until the pressure is correct

iii. If you release too much gas by mistake, air may be pumped back in with a hand - or foot -pump.