Water pump doesn't start once accumulator is emptied

[LifesBetterWhenYoureBeating]

I have a standard water pressure system on my boat, with an electric pump and an accumulator. They work fine except if a tap is opened when the pump is not energized, in which case the accumulator will be emptied and the next time I energize the pump it runs for a second (or less) and stops. From then on, opening a tap doesn't cause the pump to run anymore and I get no water as the accumulator is still empty.

When that happens I just short the two wires in the pump's pressure switch for a few seconds, and then everything is good again.

This is my first boat but I hope this behavior is not to be expected? In that case, would anybody know what could be wrong with my pump or accumulator?

Thanks in advance

[Bowdrie]

I would suspect either a defective pressure switch or a mismatch between the air pressure charge in the accumulator tank and the cut-in pressure of the switch.

[Tin Tin]

Your accumulator tank will likely have a shrader valve (like car tire valve) so you can take the cap off and let all the air out of the internal bladder. Try the pump now, as this effectively removes the accumulator function. Add pressure to the valve with a bike pump with gauge until it starts to function properly. If this does not work it may be the pressure switch (Jabsco pressure switches commonly fail for example) is faulty or maladjusted and you may need a new pressure switch. The cut in pressures will be noted in the pump and accumulator literature available by Google search.

[LifesBetterWhenYoureBeating]

My accumulator is a jabsco without the charging valve, so all I could do was "bleed" it to re establish the air cushion (as described in the manual attached). Now the pump runs longer and less frequently, but like before it still doesn't recover if the accumulator is completely emptied. Guess the most likely culprit is the pressure switch, then?

[Bellinghamster]

Most likely the pump pressure switch has failed, either electrically, or the plunger that actuates it is sticking. They're normally replaceable as a "module". If you're handy, you can disassemble it and replace just the microswitch rather than the whole module that the manufacturer sells and probably save some $, but make sure you get a replacement microswitch rated for DC and appropriate current (i.e. max pump current + at least 30%). microswitches are available from Mouser, Digi-key, Grainger, etc.