by Warren McCullough
When staying in caravan parks we have always used their showers and toilets. In most parks the amenities are first class and we often have them to ourselves. On one trip to the high country, however, the amenities were a couple of minutes walk away and when the temperature dropped below 0ºC and rain started falling – or rather, blowing horizontally in the gale-force wind – our on-board shower began to look very promising. That’s despite it being in a small ‘wet’ bathroom and having a limited on-board water supply.
That experience prompted us to consider the installation of a town (or mains) water connection in the van. Our considerations turned to action when we noticed local caravan parks implementing COVID restrictions in their amenities blocks; limiting the number of available showers and fixing markers on paths for queueing outside the building.
A town water connection provides the option of taking a shower in our van without consuming our on-board water supply. It also avoids a brisk walk to and from the shared amenities in crook weather – sheer luxury!
Doing the Sums
Installing the plumbing appeared to be relatively straightforward and not too expensive: Around $70 for the inlet panel, some PEX water-hose and fittings, cable ties and hose saddles, plus a couple of hours of labour (albeit lying on my back squeezed under the van in the driveway). Planning on a DIY installation, I dropped by our local motorhome fit-out gurus – they fitted-out our van a few years ago – for some advice. When they said, “It only takes an hour or so”, that they had all the parts on-site and that they installed these fittings regularly, my ears pricked up. And when they offered to supply and install the inlet and related plumbing for $200, I happily handed the job over to their experienced technicians!
If you choose to go down the DIY path, the only scary part of the job is cutting a 90 mm hole in the wall of the van to install the inlet plate. Alternatively, fitting an inlet connection under the floor bypasses this issue, although it’s more difficult to access when connecting and disconnecting the town water hose.
When fitting an inlet to the wall of the van, its physical location is a critical consideration. Most caravan parks provide water connection and sullage facilities on the driver’s side of an RV (when reversed into the site). This avoids having hoses draped through the under-awning living area on the ‘house’ side of the van. Unusually, our Sprinter van also has a sliding door on the driver’s side, so the inlet had to be mounted clear of it too. That made the only suitable location – other than an underfloor mount – towards the rear of the vehicle.
Given that the van’s plumbing is all under the vehicle, the mounting location was narrowed down even further. Down low on the rear driver’s side soon became the only position to install the inlet connection – in our case on the small panel just behind the rear wheel. Water pressure and flow are also important considerations when installing into a van that already has plumbing – plumbing, that is, designed for use with a low-pressure 12V water pump.
Fortunately, the widely available Shurflo town water inlet installed on our van includes a pressure-reducing valve to drop incoming water pressure to 50 psi (~350 kpa) to protect the plumbing from a high pressure town water connection. The Shurflo inlet also includes a non-return valve so that when the on-board pump is in operation (when not connected to town water) our tank water isn’t pumped out through the town water inlet. Hot water units are also sensitive to excess water pressure and so our Truma UltraRapid unit already had an inline pressure reducer, further reducing the water pressure to 30 psi (~200 kpa).
Once the inlet panel and associated plumbing are installed, the only preparation for using town water – other than connecting a drinking-water-quality hose to the wall inlet socket – is to turn off the 12V on-board water pump at the control panel switch. You don’t want it automatically cutting in and trying to pump water from your underfloor water tank when you turn a tap on (the incoming water pressure is all you need). We also connect a B.E.S.T in-line water filter between the external water inlet and the caravan park tap.
Another item to check is the van’s electrical wiring, ensuring power is still available to the toilet flush pump when the main 12V water pump is turned off. Fortunately the 12V pump and toilet in our van are on separate circuits, which saved a little bit more fiddling.
End Result
Now, when the weather turns nasty and a walk to the amenities block looks cold and miserable, we are able to take an extended shower in the van without depleting our on-board water supply. The town water supply is also available at the sink outlet and to flush the toilet. Connecting a sullage drain hose and leaving it open is also recommended: Our grey water tank holds 45 litres, but the shower head delivers 6 litres of water per minute when connected to town water and so it wouldn’t take too many showers to fill it.
The Truma hot water tank holds 14 litres, heated to 70°C. Mixed with cold water by the mixer tap in the shower, it provides more than enough hot water for both of us to enjoy uninterrupted showers (it only takes a few minutes to reheat between showers if required)!
The Surflo inlet panel features a BSP screw fitting, so a click-on adapter is required to connect your external hose. These are readily available in the gardening aisle at Bunnings, labelled as a 'sprinkler adaptor'. Spend the extra few dollars on a brass model and buy a couple for when one inevitably goes missing…
Other accessories that become useful when using the on-board shower regularly are graduated wheel levelling chocks, to ensure the shower water drains toward the floor waste, and a small squeegee for wiping down the walls and floor afterwards. A bathroom roof vent with an exhaust fan is another handy facility to help make a wet bathroom more amenable for regular showering. More information about our bathroom accessories general water usage is available at compactrv.net.