When you hooked up your water heater to the coolant lines, what did you do to bleed the system / add additional coolant? I've got the tank mounted and I'm about to source some hoses for it. It looks like you just hooked your hoses directly to the threaded fittings on the tank?I do not think the added plumbing is an issue. Other forum members and even Mercedes mount their heaters in the rear of the van. As long as you have the auxiliary pump to assist in the movement of the coolant you should be fine.
Your question wasn't directed at me, but since I recently added an Isotemp hot water tank I can say that I didn't have to do anything that special. I ran the engine for a couple minutes, revving the throttle several times. I had a helper watch the coolant level in the expansion tank and when the level suddenly dropped I stopped the motor and added more 50/50 coolant-water mix. It didn't run long enough to warm up or pressurize, just a minute or two.When you hooked up your water heater to the coolant lines, what did you do to bleed the system / add additional coolant? I've got the tank mounted and I'm about to source some hoses for it. It looks like you just hooked your hoses directly to the threaded fittings on the tank?
Yes, nothing special about the process. I did use some hose clamp pliers to pinch the lines shut before cutting my factory H88 loop. You can also employ wine or my favorite, bourbon corks, to stem any coolant leakage. I only lost about 8 ounces during the hookup and just topped off the coolant reservoir while idling the engine.When you hooked up your water heater to the coolant lines, what did you do to bleed the system / add additional coolant? I've got the tank mounted and I'm about to source some hoses for it. It looks like you just hooked your hoses directly to the threaded fittings on the tank?
That sounds like a good idea if you wanted to adjust the seat position or avoid frame members. You would need to inset the L-Track in the floor similar to my cargo floor. Which means you need to raise the floor 1/2” for vertical clearance. Not sure of the benefits of adjusting the seat.Another question on your rear seat. Did you consider mounting it on L-track? One that's strong enough for seat mounting, of course. Seems like that could somewhat decouple the seat position from the through-the-floor bolt position, dodging frame members etc. And allow for some adjustability.
I was thinking about making it so I could rotate the seat to be either on the side wall behind the driver seat or in front of the shower facing forward. L-track would make that doable, I think. Although on further reflection I think a square hole pattern just might enable that with the dimensions of this particular seat.That sounds like a good idea if you wanted to adjust the seat position or avoid frame members. You would need to inset the L-Track in the floor similar to my cargo floor. Which means you need to raise the floor 1/2” for vertical clearance. Not sure of the benefits of adjusting the seat.
A local friend did something similar but he used a Metris seat. It can mount against the wall or facing forward like mine.I was thinking about making it so I could rotate the seat to be either on the side wall behind the driver seat or in front of the shower facing forward. L-track would make that doable, I think. Although on further reflection I think a square hole pattern just might enable that with the dimensions of this particular seat.
I have used my van in freezing conditions multiple times and for extended periods. My Isotemp water heater has an Inkbird temperature controller hooked to it. The Inkbird gives me a real time readout of the water temperature. It is also programmed to turn the water heater on in cold weather. I have it set to activate at 35F. It has never actually turned on because once hot it can maintain an above freezing temperature for multiple days. The water lines are more likely to freeze due to the small volume. The portions of the lines near the water heater stay warm. All the exterior lines are heated once the temperature reaches 45F. My only freezing issue to date was a low spot in the exterior drain line. Had to run a small amount of hot water down the drain to open it up.@gltrimble Amazing build and detail in your thread. I am early in my build and this is giving me a ton of knowledge. I am finalizing my hot water system design and I am planning to go with an Isotemp + AC + engine coolant only setup. My 2020 170 Sprinter does not have the H55 or H88 options. I would like to go with a larger Isotemp like yours but I am concerned about winterizing the water lines under the van. I see you used heat trace, aluminum, and insultation on your water lines. I know some purests say not to have any water lines outside the van for a true 4 season van. Have you had any issues with the lines freezing? How did you heat/winterize the fittings of the Isotemp?
@gltrimble,I have used my van in freezing conditions multiple times and for extended periods. My Isotemp water heater has an Inkbird temperature controller hooked to it. The Inkbird gives me a real time readout of the water temperature. It is also programmed to turn the water heater on in cold weather. I have it set to activate at 35F. It has never actually turned on because once hot it can maintain an above freezing temperature for multiple days. The water lines are more likely to freeze due to the small volume. The portions of the lines near the water heater stay warm. All the exterior lines are heated once the temperature reaches 45F. My only freezing issue to date was a low spot in the exterior drain line. Had to run a small amount of hot water down the drain to open it up.
I recommend using the smaller 15 liter Isotemp. It can provide up to 8 gallons of hot water. The disadvantage of a larger Isotemp is the time and energy it takes to heat up the larger volume of water when using electricity or a diesel heater.
Yes, the inverter stays on overnight if freeze protection is required. I tested my heat tracing and although it is rated at 180 watts it only uses a fraction of that on average in sub-freezing weather. The water heater will stay warm over multiple freezing nights if it is hot from the start. I try to connect to shore power if possible when visiting ski resorts.@gltrimble,
Your posts have been very helpful! An Isotemp Slim 15 just arrived and I’m getting the other parts lined up.
Questions about the electric element and the heat tracing: since they are A/C devices, do you leave your inverter running all the time?
Where do your lines enter up into the interior?
Do you have a link for the bypass valve you used?
The manual doesn’t say anything about running the engine without water in the tank. Do you think that would cause any issues?
Thanks again.
For my water heater I used this dual DC/AC relay. One relay turns on the water heater via a 12 volt switch. The second relay activates the water heater using the temperature controller which is set for 35F. I am using a second dual relay and Inkbird temperature controllers to activate my pair of battery heaters.What relay did you use between the temp controller and the electric element. I’m having trouble locating one that triggers on 12v.
Thanks again.
Joel,-I didn’t see info on the microwave in here. Certainly could have missed it. Caught on another thread that you have a Panasonic 1.2 unit. Any special venting recommendations or insight? I’ll also have a fridge below mine so will try to get micro with same width as fridge (isotherm 115).
-what hinges (are there also separate struts) did you use for upper cab doors?
The bed panels were fabricated from aluminum to save a few pounds. I wanted to make the bed panels easy to move around so I made them out of aluminum and I made four panels instead of the usual three. Turns out I rarely move the panels and I probably overbuilt them. As mentioned earlier I could have reduced the number of aluminum spans and the thickness of the ply even more on the upper bed panels.A couple questions:
Fabricating steel vs. aluminum structures - You did the bed frame in aluminum, but I think all the other welded structures in steel. Was that for strength, cost, ease of fabrication, other reasons? I know aluminum can be really tough with a mig (have never tried it myself), but you got the bed frame looking pretty good and all the other stuff you did in steel was hidden if the welds are little ugly. I've been thinking about buying some aluminum wire and the right gas and giving it a shot. How was the learning curve on that?
I really like the water tank layout, great capacity and that location seems good for weight distribution vs. sitting in the back. It looks like the only fill option is gravity feed, right? Where does it vent to and is there an overflow of any kind? Any concerns with the tank ballooning/flexing enough to press out on the cabinet and cause problems (especially if it's overfilled)? It looks pretty tight in there.