Add-on cooling system rear heater?

[Uncle Todo]

Has anyone installed one?
My conversion van came with a rear heat/ac unit but it was rather large in the smallish space and my AC system has a massive leak. I had looked at relocating it in the van, but apparently it has to be mounted upright so I decided to 86 it.
So I already have extra coolant lines to plumb it and power to it in the back, so I thought the other day of getting a heater core to mount with a squirrel fan when I found these hot rod heaters:
https://www.jegs.com/i/JEGS/555/70603/10002/-1
Looking at the 1st or maybe 2nd one, somewhat smallish and it would only be used in case of an emergency. Another reason I got rid of the unit preinstalled was that it required the engine to be running.
I remember an old biker dude I used to know talking about how they installed 2nd radiators in the back of their vans for rear heaters.
I'm thinking in case it's, or me, is wet, freezing or other, not necessarily to heat the space.
If you've done, seen, or know of something similar, post it up!

 

[bullfrog]

My old Barth motor home had a heat exchanger in the hot water heater that the engine coolant circulated thru while the engine was running, when you parked for the night you could get a hot shower without having to turn on the propane and heat up the water. I thought about mounting a radiator above the hot water heater tank and by hooking it up to the heat exchanger using the vented propane water heater to heat the interior space while parked but never did. One of the big draw backs is you need to mount the radiator where it doesn’t need a pump to circulate the water and a fan to direct the hot air where you need it, way too much solar needed if you had to pump the water I would think but I could be wrong. It might be possible, plus you would have hot running water!

 

[bullfrog]

School buses use a similar unit you might check with some of those that have built them out for a cheap one.

 

[highdesertranger]

yeah rear hot water heaters are fairly common and fairly cheap. problem is they only work if the engine is running. so they are very inefficient unless you happen to be driving somewhere then they are very efficient. highdesertranger

 

[user 423]

Another reason I got rid of the unit preinstalled was that it required the engine to be running.

Wouldn't those Jegs heaters also require the engine to be running to get any heat?

 

[highdesertranger]

"Wouldn't those Jegs heaters also require the engine to be running to get any heat?"

yes

highdesertranger

 

[Uncle Todo]

Yes, sorry for the confusion. The engine would have to be running, but would have it in case of something happened and I needed heat like remote location and gets extremely cold, or if I get wet in the cold, something like that.
Granted I do have the front heat, but being i already have the plumbing and wiring for it figure a small unit would be easy to add.

 

[66788]

Yes, sorry for the confusion. The engine would have to be running, but would have it in case of something happened and I needed heat like remote location and gets extremely cold, or if I get wet in the cold, something like that.
Granted I do have the front heat, but being i already have the plumbing and wiring for it figure a small unit would be easy to add.

Look at VW Vanagon factory rear heaters.  Same thing but smaller and cheaper if you get one from the boneyard or from the Samba website.

 

[rvwandering]

This is one of the best mods that we've done on our RV. When we bought our first RV over twenty years ago Tony used a piece of baseboard heating fin and a 12 volt fan to build the unit. He put a fan switch on the element so that it only works when heating element is hot. The switch is inline with a wall mounted thermostat. On our current RV we had a Red Dot auxiliary heater installed but it was so noisy that Tony ripped it apart and replaced the fan with a quieter 12 volt fan. The unit is under one of the dinette seats which is about in the center of our living area. It warms the whole RV so it's comfortable while we're driving plus it's really great to have a warm RV when we stop for the day or even if we just stop to eat.

Tony also installed shutoff valves so that we don't have any hot water going back to the living area in the summer time.