Water Reticulation

Water is pumped by a 12 V pressure pump from the fresh-water tank through a non-return valve to sink, basin, shower and toilet. It also goes via a pressure reducer and safety valve to the hot water service. Hot water passes through a tempering valve to the sink, basin and shower.

When the A'van is connected to mains water, water passes from the supply hose through a pressure reduction valve and non-return valve to the house plumbing.

Water Tanks and Levels

The fresh water tank is a 62 L black plastic Hume product with all connectors at one end. The water level is monitored by a rod-type sensor fitted to the top of the tank. It is a Schaudt M 400. The level is displayed on the Elektroblock Control Panel.

The 71 L grey water tank is purpose built for the Applause, welded up from aluminium sheet. Brass one-way flap valves are fitted to the drains from the kitchen sink (under the vehicle) and the shower (at the inlet to the tank). The drain from the wash basin is looped to prevent odours entering the house. The water level is monitored in the same way as for the fresh water, but the sensor rods appear to be cut short, so that if it were to work properly, the first level indication would be somewhere near half full.

Experience has shown that the freshwater level indication in the A'van Applause is very inaccurate, possibly due to the shape of the tank. A display of 25% full is in reality about empty. The greywater level indication only works some times – unless the tank is regularly cleaned using a product such as "Actizyme" from Coles the sensor becomes contaminated by grease.

Issues

• In operation the pump made a lot of noise due to the rigid plastic piping connecting the pump knocking against the surrounds.
• At low delivery levels the pump tended to pulse rapidly, making a disconcerting noise.
• There was no filtering of water into the pump.
• The water tank inlet hose reached higher than the inlet fitting on the outside of the A'van, making filling from a container very difficult.

Plumbing Layout

All pressure lines are 12 mm blue (cold water) and red (hot water) semi-rigid plastic pipe, joined with John Guest push-on fittings (see here for how to use these). The revised plumbing layout is shown here (click for enlargement), and the changes are discussed below.

The Water Pump

This is a SHURflo 2088 classic series #2088-422-444 (Aftermarket) (...-144 OEM), a 3 chamber 12 V diaphragm pump. It is self priming, and can run dry. A built-in check valve protects the pump against high pressure in the water line (up to 200 psi).

The rated flow is typically 7.5 litres/min (2.0 USgpm) at 1.4 Atm (20 psi). Maximum current is 7 Amp.

The port threads are 1/2"-14 NPSM (US National Pipe Straight Male). These are NOT the same but are very close to 1/2" BSPM (British Standard Pipe Male). A'van had used the correct (US) John Guest adaptors to plumb in the pump.

Improving the Plumbing

As supplied, the outlet of the pump went directly to a corner connector and a set of brass connectors for a one-way valve fitting. This was not a good setup and may have contributed to excessive noise from the pump. I replaced a lot of this rigid pipework with stainless steel braided flexible hose. However these have connectors with BSP threads. On the pump inlet connection the chosen flexible hose has a gentle bend in the stainless steel pipe; using teflon tape and Hawkins Paste, I have screwed this onto the pump directly. I was careful to ensure none of the tape nor paste entered the piping. For the outlet, the US JG adaptor is retained, and a 1/2" BSPTM to spigot connector is joined to it. The braided flexible tube then screws into this latter adaptor.

The reinforced flexible stainless steel hoses on inlet and outlet eliminated two corner connectors and allowed removing the one-way valve to connect directly to a remote existing "T" connector. The inlet steel hose has a gentle right-angle curve built in so as to clear the vehicle wheel arch.

In doing these changes, JG 12 mm tube inserts were fitted to all cut ends (as was already done by A'van for their joints) and JG 12 mm locking clips were added to all hot water and some cold water pipe fittings.

Inlet Water Filter

A "hot water strainer" from FreshlySqueezed Water Company was installed near the inlet of the pump. The intention is to catch particles, rubbish and gum nuts!

Accumulator Tank

The pulsing of the pump at low flow rates was eliminated by installing a SHURflow accumulator tank in the cold water line. The precharged pressure of 20 psi (max 125 psi) was not changed, but the installation allows easy monitoring of the tank pressure, and a bicycle pump is available to recharge the tank.

Tempering Valve Noise

The tempering valve has been the source of a lot of noise as it does its job and mixes cold and fresh water to maintain a lower maximum temperature. The way it interacts with the pump results in a chattering noise that has become louder over time. I have removed the valve to stop this noise. The T-piece in the cold water line has been replaced by a joiner and the hot water line from the boiler now goes to the T-piece that was at the outlet of the tempering valve (see the layout diagram above).

Taking on Fresh Water

A dual lockable water filler is located over the offside rear wheel. A 10 m food-grade hose with snap-on fittings can connect directly to one of the filler points to supply water from the mains. A non-return valve and a 350 kPa pressure limiting valve in the line ensure a safe operation (see the layout diagram above). The water pump should be turned off when this connection is used, otherwise the pump tends to run when a tap in the Applause is on.

Alternatively, the hose with trigger nozzle is connected to the mains and used to fill the water tank through the other port of the dual filler, and the water pump does its job.

If mains water is not nearby, available water must be bucketed into the tank. A large funnel with a bend in the throat can be used, but it is very fiddly and a rigid bucket is required. Instead, I use a Primus Camp Shower plugged into a cigar-lighter socket at the back of the van and running off the house battery. I discarded the shower head, and with the submersible pump at the bottom of the bucket of water, turn on the pump and direct the water into the tank filler.

• A 15 L collapsible bucket is a good container for the water
• But since it can collapse, a tensioning elastic strap is a good idea
• The submersible pump needs to have silicone grease applied to the impeller shaft to stop rusting and seizing of the motor
• Of course, the Camp Shower can also be use as intended — to take a shower.

Update

The submersible pump in the Primus kit is rubbish and soon seizes up with rust. I have replaced it with a Rule 12 V 360 gph bilge pump from Whitworths Marine where it is occasionally on special for under $20. To fit the shower hose I inserted a 12 mm plastic joiner in one end and jammed the now-expanded hose into the pump outlet.

LINKS

• A'van http://www.avan.com.au
• FreshlySqueezed Water Company http://www.freshlysqueezed.com.au
• NEFA (Methven) http://www.nefa.com.au/
• Primus Australia http://www.primusaustralia.com.au/
• Whitworths Marine http://www.whitworths.com.au

Water Supply

The water filter is circled in this early photo, which also shows the rigid inlet piping

Accumulator tank (pressure vessel) mounted on wall of bed base in the cold-water line to the sink.

The inlet flexible hose (A) with gentle right angle. The outlet flexible hose now locates the non-return valve at the "T" piece (B) well away from the pump, and the outlet from pump (C)

Orlando Euroblock PN40 DN10 non-return valve

NEFA TMV15 tempering valve sets the delivered hot water temperature to ??

Setting up the Primus Shower pump to fill the Applause water tank from a bucket