Replacement/Spare water pump......or pressure switch?

[BGD]

Hi peeps -

 

 

The present water pump in our 12 year old, Spanish registered Benimar motorhome is, I suspect, the original.

I think it's a sort of bog-standard Fiamma brand pump.

It's cylindrical, bolted onto the top of the freshwater tank under a dinette seat by four bolts, has a pipe feed in on the right via a little filter, out to the left, and a pressure switch on its end, fed by two spade- connection 12 volt cables.

 

The pump details (from the info plate on it's side):-

 

Superflow 126 PRO

Cod: 012 16001 -

No: 01 011 3

Feed: 12

Max Load: 6 L/min

(something) of pressure switch: 1,3 bar

Fiamma.

 

 

 

It functions fine, but on our last trip I noticed that, only very occasionally, it took longer than usual for the pump to kick in after we'd opened a tap, or turned on the shower.

Thus in the shower for example you'd get an initial burst of water, tailing off within a couple of seconds to nothing, then after perhaps a second or two you'd hear the pump kick in and the water pressure from the shower head would then be restored within about a second.

 

Also on our last tour, (but on only two occasions that I noticed in the whole month in the Motorhome, so very rarely indeed), after we'd run the tap in the bathroom for a few seconds to wash hands, and then turned it off again, the pump stopped a second or two later (as usual) but then about 10 seconds later it ran for a few seconds; then stopped, and then did the same thing 10 seconds later, over and over.....as if it was cycling over and over again.

To stop it, both times it happened, I turned off the pump power at the van control panel, waited a couple of minutes and then turned it back on, and the pump then behaved properly.

 

 

 

I've checked all pipe runs and all joints: there are no leaks anywhere, and at no time have there been any "splutters" of air in the water as it exits any of the taps.

 

 

So...........I'm suspicious of the reliability of the pressure switch attached to the end of the cylindrical pump body. I'm guessing it's maybe getting knackered and is playing up a little now and then.

 

 

 

 

My questions, to all learned water pump techies are:

 

1. Is there any maintenance/adjustment/lubrication that I can make to the pressure switch?

 

2. If indeed it's starting to get a bit unreliable and can't be adjusted, is it simply a question of obtaining and fitting another switch (if so, from where please via mail order for this model of pump)?

 

3. Or is it a question of buying a complete new pump, with the switch being an integral part of the pump? If so, can anyone recommend a good supplier of this type of pump please..........

 

 

 

 

As we do travel around a lot, for longish periods, I am tempted to buy another pump if needs be, and carry it as a backup anyway.

 

 

 

 

 

 

All techie info and advice greatly appreciated................. :-D

 

 

 

 

[Robinhood]

The Fiamma pump on my Benimar was a little "temperamental" particularly after standing for some time between use.

 

In common with all (?) pressure-switched pumps, there is an adjustment screw on the end of the switch unit (identified by the wires going in and out) which allows you to adjust sensitivity either way.

 

If there is nothing else wrong with the unit, the trick is to find the "sweet spot" for the switch, which causes the pump to come on as soon as pressure drops, but also to turn off as soon as it rises.

 

I can't remember which way the adjustment is to make it more sensitive to pressure drop, so you may need to use trial and error (but only move it in small increments).

 

Edit to add

 

I think the problem is that, over time, the rubber diaphragm that acts against the switch tends to harden a bit, requiring adjustment.

 

I believe the 126 is now obsolete, but the pressure switch appears (from spares listings, though you should check) to be the same as that used on the current Aqua8 pump, so should be relatively easily available.

[laimeduck]

Bruce - this may be of no use at all but this is the pump fitted to my Benima. The location of yours sounds identical to mine.

 

http://www.fiammastore.com/Fiamma-Aqua-Pumps-for-caravans-and-motorhomes/Fiamma-Aqua-8-pumps

 

I have rewired mine to a separate manual switch & it works fine.

(I had some strange electrical gremlins related to a grey-water tank electric dump tap which wasn't fitted to my van, but the control panel said it was!! - don't ask!)

[BGD]

Thanks guys for your help.

 

Great to learn that the sensitivity of the pressure switch can be adjusted - thanks Robinhood.

 

There is indeed a little allen-key headed adjuster screw on the end of the pressure switch on my pump....that end of the pump is fairly tight to the the wall of the MH, but I managed to identify it using one of Kathy's 40,000 make-up mirrors.

 

Using a number 2 allen key, I can turn it in/out, so for a starter I've turned it clockwise about 10 mins (if visualising the end of the pump as a clock-face), and we'll see how we go.

 

 

 

 

 

 

As an aside, I too have a motorised dump valve on my Benimar grey water tank. The valve is one of those American RV style jobbies, with maybe a 3 or 4 inch throat. I have to say that I think these RV style waste valves are brilliant; far better then the tiny diameter piddly valve/waste pipes that I've been used to on previous motorhomes.

The 100 litre greywater tank, and the actual dump valve itself which is attached to the bottom of it, is just inside the side-skirt of the van.

The idea is that you can just drive over a grey water dump point and then open the valve from inside the van, using a rocker switch on the control panel.

Works really great!.

But, we wild camp a lot, without access to "proper" grey water drive-over dump points; and so often I prefer to empty my grey water into a big bucket that I carry, and then walk to a drain with it.

I also tap-off some grey water into the bucket sometimes to use as rinsewater for my toilet cassette.

The motorised valve is an "all-or-nothing" jobbie and it's diameter is BIG......if you open it fully, it'll dump a whole 60 or 80 or 100 litres of our grey water in maybe 10 seconds.

 

So for now, I've removed the motorised valve part and replaced it with a bog-standard RV slide-valve with a manual pull/push remote handle. Now, although I obviously have to get out of the van to do it, I can open the valve as little or as much as I like...and if filling my bucket, I can shut the valve again. Lovely jubbly!

[Derek Uzzell]

There are Aqua8 servicing video-clips here:

 

http://www.fiamma.com/EN/service/video/advices/

 

The Aqua8 instructions for use make no mention of pressure-switch adjustment. A drawing on Page 4 seems to suggest that altering the setting of the adjustment-screw (in the centre of the pressure-switch's end-face) should not be carried out, but I think it's just warning against using a screwdriver. For an Aqua8 (and possibly the earlier "Superflow" pumps too) I think an Allen key may be needed to to adjust the pressure-switch. (Edit: You beat me to it!)

 

For motorhomes, Fiamma and SHURflo are probably the diaphragm water-pumps most commonly fitted, though Whale, Flojet, Posiflo and Inovtech are other brands. In the UK, a SHURflo Trail King 7 20psi (which would be roughly equivalent to your quoted specification for your Fiamma pump) would be around £50, while a similar specification Aqua8 usually seems to be offered at £70+.

 

This supplier offers a pressure-switch assembly for an Aqua8 at £11.68

 

http://www.marcleleisure.co.uk/store/-c-330_406.html

 

Assuming that this would fit your pump, as the assembly seems to be relatively inexpensive, you might find that you can obtain it locally for a price that would be as cheap as buying it outside Spain and incurring mailing charges.