Water System

Why we hired it out

With electrical, if something goes wrong (and you’ve taken precautions) a fuse blows or a breaker trips. With water, a slow leak behind a wall panel can quietly destroy the van over weeks without you noticing. That’s what pushed us to hire a van builder rather than do it ourselves. We also wanted more than a basic water system, and using a pro-builder meant we got more niceties in the overall system.

The system

The builder installed an over-wheel-arch fresh water tank, an underslung gray water tank with an electric ball valve to dump it, and an Isotemp water heater that pulls heat from the engine coolant — hot water while you drive, no battery required. They also fitted an Espar diesel cabin heater under the passenger seat while they were in there.

A lot of people go the two-jug route: fresh water jug under the sink, gray water jug to catch the drain. It’s simple and it works, but it rules out hot water. Hot water was the thing we weren’t willing to give up, so we went with custom tanks and an outdoor shower on the back.

One thing worth knowing about the coolant tap: it adds a dependency. If you’d rather keep the plumbing and the engine completely separate, electrical-only heating is a sensible call.

Hot water

The Isotemp does what it says. After a drive the water’s properly hot, and it stays that way for about 12 hours before dropping to lukewarm. Since we’re driving most days that’s fine. For the days it isn’t, there’s a 400W heating element — 20 minutes off the battery and you’re back.

The sink is big and deep and was worth whatever it cost. Doing dishes in a camping-sized sink is genuinely miserable; doing them in this one is not.

Hot water also means you can do a rough wash inside the van — enough to feel human again — which buys more time between proper showers than you’d think.

Capacity and daily life

29 gallons fresh, 5 gallons in the Isotemp tank. About 34 gallons once everything’s full. As two people with a dog, that’s a comfortable five days. A week starts to require some thought.

Figuring out water capacity is harder than figuring out electrical. With electrical you can calculate loads and run times. With water it depends on how you cook, how you wash up, whether you’re using the outdoor shower. We landed where we did mostly by feel. It turns out five days also happens to be roughly how long we’d go before wanting to restock food, so the timing works out.

Drinking water

We have an inline activated carbon filter on the drinking water. It doesn’t make questionable water safe — you still need to fill from a potable source — but it takes the edge off any weird taste or smell, which matters when you’re filling from municipal taps that vary a lot in quality. If you want to go further, UV filtration systems will handle more serious water quality concerns. We didn’t feel we needed that, but it’s a real option.

What we’d do on van 2

We made a mistake installing a diesel heater on the petrol van. Originally this was to avoid needing to tap into the fuel tank (because we thought we were doing this all DIY) but the pro builder could have done this, and it would remove the diesel-vs-petrol complexity (and diesel smell!). We would also very likely ad an interior shower. Some of that is just us getting older, some of it is that a shower cubicle doubles as a toilet room, and right now we have zero privacy — our composting toilet pulls out from the bench seat by the sliding door, and you use it in the open van. It’s fine. It just occasionally involves asking the other person to take the dog for a walk right now please and knock before you come back in.