Water pumps

[Vic]

I'll start off with the sob story. Early February my home gas boiler gave up the ghost. Ergo, no heating or hot water. No problems here I thought because we can use space heaters in the house and shower in the van. After two weeks, the water pump in the van stopped working. I phoned my local dealer as the van is still under warranty and surprisingly, he sent a man out to fit a new pump. The young guy who came out to us said that the pump would take around 10 minutes to replace. After about 45 minutes of going backwards and forwards he said that a valve on the external drain system was, how shall I say, knackered.

 

My question is, if he had fitted the pump incorrectly, would this have caused the damage to this external valve? I tried the pump after he'd fitted it, and it was extremely noisy.

[davenewellhome]

Not quite sure I understand your post fully Vic. To start with if he has fitted a replacement pump of the same type and size as the original there is no reason why it should be noisier. Secondly, how could the fitting of the new pump affect this "valve" on the external drain? What could he possibly have needed to touch the external drain valve for? Is this the external fresh water tank drain or the external waste tank drain?

 

D.

[Vic]

Dave, this was the external valve for draining from the fresh water tank. I just wondered if the pump was fitted incorrectly and pumped outwards instead of inwards, would this have damaged the external valve? This question obvously shows that even after a year, I'm a motorhome virgin.

[davenewellhome]

No worries Vic, we all learn as we go along. I'm sure I speak for all the "experts" on here when I say we're all still learning :-D .

 

There is no way I can think of that the pump could damage the drain valve on your fresh water tank. Even if it were mounted the wrong way all it would do is pump air into the tank and blow bubbles in the water.

 

D.

[Brian Kirby]

It's a bit like your house, Vic.  At home, you have a water supply to your kitchen fed by pressurised water mains.  When you open the kitchen tap the mains pressure ensures water flows.  Your van has no pressurised water mains, so uses a pump instead, to lift water from your fresh water tank so that it flows from the taps.  Because the pump is electric, and your use of water intermittent, it is usual for the various taps in the van to include microswitches so that when you turn the tap "on" you also turn on the pump, and water duly squirts forth (or should!).

Again in you house, the water now in your kitchen sink eventually flows away to the drains.  However, your van has no drains so must temporarily store the waste water in a tank.  Pipes connect the various sink, washbasin and shower outlets to the waste tank.  Periodically, you have to empty the waste tank, and this requires a valve, or tap (sometimes called the dump valve), so that you can release the waste water to a drain.  It is this valve it seems your fitter pronounced as knackered. 

As you can see from the above, it has no connection with the fresh water supply, nor the pump.  However, the weather has been very cold and you have been showering.  Did you leave the shower water in the waste tank rather than emptying it daily?  If so, it may well have frozen, with the ice knackering the valve.

Why might the new pump be noisy?  Possibly because the fitter has overtightened the anti-vibration mountings fitted to most pumps, negating their a/v qualities, possibly he has slightly misaligned it so that it is in contact with something else, or possibly the cold weather has temporarily hardened the plastic pipes so that they are transmitting the resonance of the pump more than usual.  Or, it is a duff, or wrong pump; or you are imagining it!  :-)

[BrianR]

Two things you could check. Firstly, is the new pump properly secured to the floor, or to whatever it was originaly fastened, including vibration absorbing washers? Second, is it the same make as the original? I know what a difference this can make, as last November I had to fit a new pump and I had to change my Shurflow for an alternative brand (Shurflow not being available where I was in France) and the replacemant is much noisier. If you travel abroad you will notice that the pumps on Continental vans are much noisier.

[Vic]

Thanks to all for the advice. My drain from the shower etc was left open, going straight into my 'Wastemaster'. Yes, the cold snap may have frozen some of the pipes,so, I'll just have to wait and see what happens when the repairs are done. Thanks again for the advice.

[Guest Tracker]

A newly fitted pump may simply be noisy due to pockets of air still remaining to purge themselves from the system which they will in due course.

 

This can often be verified by closing the tap and seeing how long the pump 'ticks' for as it compresses the air in the pipes - because it can't compress water the ticking stops after a second or two when no air is present.

 

As others have said, the rubber mountings of the pump base should only be just tight enough to stop the pump from wandering about in it's locker and not so tight that it can't move to absorb noise and vibration as it works.

 

Ensure that the filter housing is done up tight and that both pipe connections are tight, as a reused jubilee clip tightened on an already compressed pipe can suck in small amounts of air without necessarily leaking water.

[trooper]

I think its worth mentioning that there are usualy two types of water pump systems fitted to M/Homes, the presurised system using a diaphram pump, often a bit noisy, and switched on automaticaly by a pressure switch. (I prefer these although these make more noise if not fitted correctly)

The other is a submersable pump which is swithed on by micro switch in each tap, as in my burstner, these are normaly quieter.

[Derek Uzzell]

There's also a 'hybrid' type of motorhome water system that uses micro-switches on the taps that trigger a pressure-sensitive diaphragm-pump. This is the arrangement favoured by Hobby on some of its models.