Water Supply – For the plumbing of the van we have the three 16 gallon water tanks that are all connected together. Two under the sink, and one is on the other side of the van, next to the water heater. The reason for this is weight distribution. You want to weight evenly distributed across the van. Remember one gallon of water weighs 8.3 pounds, so 16 gallons = 132+ pounds! Also, having several small tanks eliminates the need for baffles. If you only have one tank without baffles, there would be a great deal of water movement when braking. The tanks are connected together with 1/2 inch PEX pipe. This allows the water to flow and even out between the tanks. The videos below detail the installation.
Water Filtration System – Having clean safe drinking water is important. Most van builds have some type of filter. I went to the extreme and put in a reverse osmosis water purification system. The process of running water through a RO system wastes a lot of water. So, when I installed the system I put in two valves, basically switches so that I have the choice of running the water through only the filters, or through the filters and the RO Membrane. When we are getting water from what we consider is a safe source, we use just the filters. But when the water is from a river, stream or some questionable source we can use the RO system.
Another benefit of the RO system is the pressure tank. By having this pressure tank we always have water pressure even when the pump is off. So, we don’t need to turn on the pump just to get a glass of water or to wash our hands etc. The video below shows the installation and how our water system works.
Water Filtration System Install
Grey Tanks – We have two five gallon tanks under the van. One tank is for the recirculating shower, the other for the sink. Both tanks fit up between the frame of the van and are not readily visible from the side of the van. Both tanks are connected to electronic ball valves. These ball valves allow us to flip a switch and drain the tanks. See the video’s below for more information.
Water Tanks –16 Gallon and 5 Gallon
PEX Pipe – In your van build you will be using 1/2” PEX for all your plumbing. There are several different types of connector systems. Crimp, Clamp, Push-to-connect, Expansion and I am sure a few more. I decided to use stainless steel clamps. Simple, effective and easy to replace if needed. I did not have any failures or leaks using these clamps.
I didn’t try the expansion type fitting because that requires you to have access to the end of the pex pipe which may be difficult depending on the location. It’s difficult to explain. Below are the materials and tools used for the plumbing:
Ball Valve with AutoReturn 
Ball Valves, manual function and auto-return
Heat shrink tubing Clear and large color coded.
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