# Water pump on constantly



## DocHoliday (Jul 18, 2008)

Noticed this afternoon that the water pump on my 2003 B544 Classic is on all the time. The only way to stop it is to turn off the 12V circuit. I think I've correctly identified the cause as a faulty microswitch in the bathroom tap. There is no 'click' heard when opening and shutting the tap, whereas there is a distinct click from the kitchen tap and the loo flush. Could it be anything else? The Truma frost protection valve is shut.

I'd rather not wait for Hymer to send out the part as I'm away from home, so is there anywhere near Bournemouth that might have a replacement microswitch?


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## Andysam (May 10, 2005)

Sounds like a microswitch. They are not in the main manufacturer dependent, so any caravan dealer will have them.


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## aultymer (Jun 20, 2006)

As a get you home measure you could just remove the wires from the microswitch and fit a 12volt switch from Halfords or the like. Not pretty or as smooth as the automatic microswitch, but would keep you going till you get home.


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## TheLizard (Jan 23, 2008)

Hi DocHoliday

Had the same problem so pulled the tap handle off, it should just be a push/pull fit and then you should see the microswitch....if you are sure it is the microswitch that is not working then cut the wires and fit a 12V on/off switch as Aultymer suggests in order to get you home.

Your tap is probably made by Reich and the microswitch is clipped into a housing, by dislodging a small clip you should be able to lever the switch out! I found my replacement at Leisureshopdirect here http://www.leisureshopdirect.com/caravan/home/search/Microswitches_for_Reich_Taps.aspx

Good Luck 

Tony


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## BwB (Dec 5, 2009)

My water pump also has a pressure switch which stops the pump running once the water pressure in the pipes is up to a set level. 

When I left a tap not quite turned off enough to click the switch on the tap but enough to stop the water, the pump would run for a few seconds every minute or so.

If the switch on the tap doesn't fix your problem, the next thing to try is if you have a faulty pressure switch.

Incidentally, the switch in my tap had "shifted" a tiny bit which is why it was not clicking off, so before you snip any wires....just check it doesn't need reseating.

Bryan


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## erneboy (Feb 8, 2007)

I have often opened faulty switches and repaired them. If you are sure it is the switch why not have a go, nothing to loose. It can take a bit of close study to see how they come apart, usually all there is inside is a spring contact and a couple of terminals to which the wires attach, Alan.


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## DocHoliday (Jul 18, 2008)

Bryan, I'm not aware of there ever having been a pressure switch in the pump - do they all have them?

Erneboy, I'll give it a go - have tried opening and mending larger switches before with some success and as you say, nothing to lose.


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## aultymer (Jun 20, 2006)

I think Bryan is talking about systems which do not use microswitches.
Our Rapido has a pressurised system hence no need for microswitches.
Our last Hymer had started off with microswitches but somewhere in its 15 year life these had given trouble and a previous owner had fitted a pressure sensitive pumping system.
Putting a microswitch in a water tap is to me a dubious practise (water and leccy seldom mix well) however the downside we found with the pressurised system was demonstrated when a broken plastic hose clip allowed the pump to empty the water tank onto our floor before we realised there was a problem.


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## erneboy (Feb 8, 2007)

A 12 volt switch near a tap only breaks the live, this poses no risk to you at all. Although water in the switch might possibly prevent the switch functioning in the off position and make the pump run, Alan.


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## BwB (Dec 5, 2009)

Not sure where the pressure switch was, sorry. I presumed inside the pump.

(Maybe the pump had been changed for a pressure sensing one before I owned the 'van? But the tap switches were still part of the system. This was in a ten year old 1991 'van, which turned out to have some interesting DIY bits on it) :roll: 

Back to the initial question though; as you have switches on taps presume faulty switch/misaligned switch/dirty contacts switch.


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## aultymer (Jun 20, 2006)

Hi Alan, my dislike of microswitches on taps was not prompted by any thoughts of danger but rather from an engineering consideration where, if something can leak, it will. 
A water tap is going to be turned off by people with wet hands, eventually the tap fittings will leak and water reaches the terminals of the microswitch - end of microswitch and, if left long enough, you get 'black wire' syndrome and need to a bit of rewiring.


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## DocHoliday (Jul 18, 2008)

I tried to dismantle the switch but had no luck, so I cut the wires. That stopped the pump. I shall look locally for a switch and failing that, order online using the link above.

Unfortunately, there is now greatly reduced flow from the pump. It must have been on constantly for a couple of hours yesterday before I noticed it. I have had reduced flow symptoms in the past caused by the pump outlet hose coming partially unsecured and leaking, but that's not the problem this time. That symptom together with the faintest whiff of burning electrics smell in the water must mean the pump is on the verge of failing. More expense!


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## DocHoliday (Jul 18, 2008)

I got a new pump and microswitch at Autovan Services, Wimborne. The Reich pump was a reasonable price - about £29.

The flow rate is better but still not spectacular, especially to the loo flush, but my leisure batteries are a bit depleted so that's probably the cause.


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