Redo the plumbing and moving flat plate water heater inside
I guess I should introduce myself first, my name is John and my wife and I own a 06 EB 6.0 Diesel with a slightly modified RB50 build out (we had it pushed back about 7" so we would have a little more room in the living space and there is still room enough in the back for two bikes). We picked up our van in January 2007, and from the start I had planed to install what I could myself to save some money and do things the way I thought they should be done. A few of the first things I did was tint the windows, install a bigger transmission cooler, install the Espar coolant heater and furnace, make custom space efficient drawers, install a back up camera, solar panels and controller and so on. In the four years we've had it, it's never stopped (just ask my wife) and now that I have discovered this forum, you guys have given me all kinds of new project ideas and solutions to problems I didn't even know I had. Don't even ask why it took me so long to hear about this forum, all I can say is I'm not very computer savvy. The only help I had was Eric Badge's Blog, my wife found it while we were in the process of having our van built. By the way, if you come across this post Eric, thanks for that. So now I have some catching up to do. Unfortunately for most of my mods an self installations, I was not taking pics of my process and/or progress, so I will only have pics of the finished product of most things.
I will post these separately to make it easier for the search function.
One of the last big projects that I took on was to redo all the plumbing in the van. We do our share of cold weather trips and we have had a lot of problems with our lines freezing. I think the biggest contributor to this (as anyone that has this type of water heater will know) was that the flat plate water heater was mounted outside. I have wanted to move it inside for a long time, I saw that Eric Badger had done this and I knew that it would help. When the original flat plates were recalled and we were up at SMB west having ours replaced, I ask what they thought of putting it inside and they said it was a bad idea. The risk of the coolant contaminating something was to great. I didn't buy it for a second but that was all my wife needed to hear. So all I could do was try to insulate the heat exchange where it was. I built an enclosure and with access to the drain valves insulated it as best as I could. This helped a little but the lines would still freeze on occasion. Until last March when we were on a month long ski trip and a few 1 degree nights sleeping in the June Mt. parking lot, the flat plate ruptured. Even though I had shut off the supply valve and drained the core. It turns out that the valves in the shower also were damaged and the heater was refilled with back flow from the shower. Fortunately the coolant ports staid intact so there was no big mess. It was over $400 to replace that heat exchange so that's when I started drawing up the plans to move it inside.
The first thing I had to do was convince my wife that it could be safe (after spending the money for a new unit, this was a bit easier to do). I just had to put a "worst case scenario valve" in the coolant lines.
This cluster of three ball valves allows me to completely bypass the flat plate or minimize the amount of hot coolant that passes through it, to control the temperature of the water from the faucet, without cutting flow to the Espar coolant heater. And this has been mounted where the flat plate use to be.
I put the heat exchange in the cabinet under the sink. I am obsessed with maintaining as much storage space as possible so I wanted to take up the least space that I could. I was able to put it under the self in that cabinet and only lose a 7"x 8" spot on the floor.
It's hard to see in the photos but I put a shutoff valve on the supply and exit of the potable water so there can be no back flow. I also put a drain valve on both ends so there would be an air supply for a quick and complete evacuation of the water. Those are the two lines you can see going into the floor. And all of these valves are 1/4 turn ball valves with Pex fittings. I built a two sided enclosure and put a double layer of bubble insulation on all the inner surfaces to minimize the heat that might build up in the rest of the cabinet.
This has all been working quite well but we have only been in temps in the low 20s, so far.