Built-in pass-through water heater, anybody done that?

[RoadForce]

So I was wondering if anybody has successfully included one of those portable water heaters in his rig (trailer, popup, whatever...). I would like to know how you did it. Care to help a buddy out and share some details?

I am referring to the portable, pass-through kind that is supposed to be used outside, like this:

I really like the tankless design and on-demand, "unlimited" hot water these devices offer, but I don't like the hassle of hooking it up and packing it up every time I want to set / break up camp. So, I want to permanently incorporate it into my homebuilt truck camper, and I was thinking of putting it inside some kind of "gas box"-like space: a space that is air-tight to the inside of the camper, but well ventilated to the outside.

But here's my concern: as these heaters don't really have a dedicated air inlet and outlet, I am worried about "circular airflow" causing problems (when the exhaust gases are sucked back into the flame). Will this be a problem, or would e.g. a couple of these mitigate that problem?

 

[colorado matt]

while I can not answer specifics I can say yes ... many have done it ..... being a long time lurker short time member I have seen lots .... look under trailer builds and search hot water or on demand hot water ..... while many have it where there is some set up and break down there are some that have it hard mounted and it works just the same ..... I will do some searching and try to find an example for ya .... Matt

 

[RoadForce]

Thanks Matt, I appreciate it!

I will also do some searching, and I do recall seeing hard mounted units but IIRC all the instances I came across, had some kind of panel/hatch that was to be opened when using the unit. That is something I'd like to avoid, if possible.

 

[AFBronco235]

You can also make your own water heater that uses waste heat from the engine cooling system to heat the water. All you need for that is the heat exchanger, which allows hot water from the engine to heat water from your tank without allowing them to actually mix, and some rubber hose. No ventilation needed. The downside is that you do need to have your engine running, but the upside is that it is a simple enough mod to do and doesn't take up a lot of space, if any. In fact, the one time I've seen it done on here was in a bronco where space is at a premium. He used it for a field shower setup.

 

[RoadForce]

Thank you for the suggestion, but: no.

Haha :wings:

I am building a slide-on truck camper, that will be used both ON and OFF the truck, so it will have to work stand-alone, without the truck. Of course, I can still fit a boiler of some sort, but that hot water supply is limited to the size of the tank, and takes quite a while to heat up. I really like the "endless", on-demand supply these portable puppies offer, but then I don't want the hassle of setting it up everytime...

 

[toymaster]

Eccotemp makes the heater you have pictures. If you want to do it correctly they do make indoor units that are vented. Not to much more and you have a properly engineered duct system that is safe.

https://www.eccotemp.com/eccotemp-i12-lp-indoor-tankless-water-heater/

I use one like you have pictured with my horse trailer. Veritable pet washing station. Of course, works well for human too when out there at the trail head. Pay no attention to the dude riding my mule he just wondered up one day and I took pity on him, let him ride my Molly.

 

[RoadForce]

Thank you toymaster, I did not know about an indoor model. I will check it out!

 

[RoadForce]

You have given me a few things to think about, thanks for sharing your experience.

 

[pappawheely]

I have a build in process using an ecco-temp on demand unit. It is important (per ecco-temp) to use a stainless exhaust tube. My unit will vent through the side of the box. The unit will be in a compartment sealed to the interior. The compartment will draw outside air in through the bottom and vent out the top to remove all gasses. Since the burner only ignites when water is flowing, I don't foresee a lot of residual heat build-up. I won't be taking long showers in order to conserve water.

 

[RoadForce]

That looks like a nice setup! Which model is that?

I read up on the indoor models and noticed they specify stainless steel exhausts, staight or angled ones. Do Eccotemp specify any details on the air channel for the inbound flow (location, dimensions, etc)? I didn't find any.

 

[RoadForce]

What about an Atwood tankless on demand water heater? I find myself looking at one of these more and more:

http://www.amazon.com/Attwood-90205-On-Demand-Water-Heater/dp/B007S3MTI8

Seems to get good reviews. True, it is more expensive than e.g. an Eccotemp indoor model (and living in Europe doesn't help with that!), but the facts that it vents through the door/hatch and it not as tall (~15 inch, which suits my design a lot better) make this model very tempting.

I did a search on these forums and found only very few references. Nobody uses such a model? Why not?

 

[pappawheely]

That looks like a nice setup! Which model is that?

I read up on the indoor models and noticed they specify stainless steel exhausts, staight or angled ones. Do Eccotemp specify any details on the air channel for the inbound flow (location, dimensions, etc)? I didn't find any.

The Eccotemp L10 Thankless Water Heater is one of the hottest thankless water heaters on the market! The Eccotemp L10 Thankless Water Heater gives you endless hot water at your cabin, summer cottage, lake home, potting shed, RV, camper, horse washing stall or wherever else you need hot water. The Eccotemp L10 Thankless Water Heater delivers up to 2.6 Gallons Per Minute of hot water ranging from 80-165 degrees F, plenty for 1-2 hot water applications running at the same time. The 2 "D" cell battery ignition starts the flame only when water is running, so there's no chance of overheating. It is perfect for off grid or areas where you have limited electricity. Designed for a more permanent installation, the L10 comes with standard 1/2" NPT fittings, making it easily plumbed in with standard fixtures. The ideal operating range is 25-80 PSI. The system also works great on modified water systems with items such as a 12 volt pump.

 

[RoadForce]

Thanks papawheely!

And just to quote myself:

What about an Atwood tankless on demand water heater? I find myself looking at one of these more and more:

http://www.amazon.com/Attwood-90205-On-Demand-Water-Heater/dp/B007S3MTI8

Seems to get good reviews. True, it is more expensive than e.g. an Eccotemp indoor model (and living in Europe doesn't help with that!), but the facts that it vents through the door/hatch and it not as tall (~15 inch, which suits my design a lot better) make this model very tempting.

I did a search on these forums and found only very few references. Nobody uses such a model? Why not?

I started a separate thread to answer this question: http://www.expeditionportal.com/for...er-heater-in-a-quot-family-adventure-quot-rig

 

[pappawheely]

The Eccotemp L10 Thankless Water Heater is one of the hottest thankless water heaters on the market! The Eccotemp L10 Thankless Water Heater gives you endless hot water at your cabin, summer cottage, lake home, potting shed, RV, camper, horse washing stall or wherever else you need hot water. The Eccotemp L10 Thankless Water Heater delivers up to 2.6 Gallons Per Minute of hot water ranging from 80-165 degrees F, plenty for 1-2 hot water applications running at the same time. The 2 "D" cell battery ignition starts the flame only when water is running, so there's no chance of overheating. It is perfect for off grid or areas where you have limited electricity. Designed for a more permanent installation, the L10 comes with standard 1/2" NPT fittings, making it easily plumbed in with standard fixtures. The ideal operating range is 25-80 PSI. The system also works great on modified water systems with items such as a 12 volt pump.

I will quote myself too. I cut and pasted that text from Amazon; just noticed it says THANKLESS water heater, HA Ha.

 

[RoadForce]

Haha thankless, priceless!

You almost had me thinking you were a sales rep for Eccotemp with the text you posted, but I got the information from it that I was after: the type / model number.

I hope your unit delivers what you got it for, please report back when you get to finally using it!