12V pump and water filter installation

http://s26.postimg.org/66ogrkhzt/caravan.jpg

Afternoon Toby.
Firstly I couldn't see your drawing, but it is quiet simple.
I would rather see a Flowjet, Flowking or Johnson pump, with a pressure switch, more expensive, but are quality. $55 for a 10lt/min pump is very cheap, I would not expect it to be much chop or have a pressure switch, save money on your filter by installing an inline filter, something like an FSA, more than ample and a third of the cost of what you linked to.
Install a Y valve between your pump and tap, that's where your mains feed will connect to, your filter then can be placed between the Y valve and tap, all your water will be filtered, and all you have to do is flick the valve for what water your on. So tank feed into pump, then Y valve, mains feed into Y valve, filter, then tap. Also mount a simple switch for the pump, so if your main runs dry, you can isolate the pump and stop it from burning out, be sure to place an adequate fuse in the power feed to your pump. You do not need to waste money on that tap either, you already have a filter inline and your not running hot water are you ???.
Cheers Tony F8

Hi Toby,

Here is a simple diagram I have drawn up showing correct method of installation.

Note that you do not connect the hand pump into this system. It is a stand alone setup as it has no valving to withstand the pressure from either the on board 12 volt pump or the mains pressure.

It is essential that you fit a pressure reduction valve at the inlet point of the mains feed to the van. This is to safe guard the pressure pump diaphragms from excessive mains pressure.

Control the incoming pressure back to a point about or just below the operating pressure of the 12 volt pump you choose.



Cheers, Bruce.

Hope this helps, Bruce.

If you have a simple hand pump at present, then just install an inline 12v pump before the hand pump. The water will flow through the outlet as if you were using the hand pump, the non return valve in the hand pump will double for the inline pump.
The hand pump handle may rise in the process of using the electric, but this is of no concern.
The easiest way to control the pump is with a momentary contact push button switch somewhere convenient to the tap. Water will flow whilst ever you keep the button depressed.
You can still use the hand pump to both fill things manually (good for controlled flow to fill ice trays etc) and to prime the electric pump if you happen to run out of water.
It is important that you don't allow these inline pumps to run dry.