Dometic RM182B exhaust mod

[DanHoug]

there's probably a thread this should be tagged onto, Mods, feel free to move....

added insulation to the exhaust pipe on the fridge. this accomplished 3 things, all good:

- greatly reduced heat released to interior and specifically to the area around the fridge, increasing the Delta T between the heat sink fins and the ambient air.

- increased the stack temp of the exhaust and eliminated 'the drip' from condensing acidic water vapor from the flue vent. this, IMHO is why there is seam rust on the kitchen side. it is not from the water connection, it is from the acid rain that falls between the aluminum intake/outlet piece and the rubber gasket and dribbles inside the body panel.

- increased the flue temp differential which results in greater draft between the exhaust and intake lines. results in a better burn. just like hot rodders wrap headers to conserve the energy of the exhaust cooling and creating slower boundary layer, the insulation keeps the pipe temp up for better flow.

i started with a wrap of quality header wrap. while the temps are low, the cheap offshore stuff actually burns up on the manifold. pretty crucial application on the interior so spending an extra bit to get the good stuff is wise. used Design Engineering header wrap, serving the hot rodders for generations.

then, because it is so dang fast and cheap to do, made a wrap of aluminum foil to add an IR reflective layer.

the results are great. NO vent drip, yes the vent cover is hot now, no the rubber isn't melting. reduced interior temps behind fridge, the fan cycles less. i'm happy.
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-dan
60% of what you find on the internet is wrong, including this post.

'87 Westy & '89 Westy both 2.1 4spd

Past projects can be found at--
www.thefixitworkshop.com

[Yellow Rabbit]

I like it. I’m surprised the factory didn’t do something like this. What was the change in interior temp?

[SSWesty]

Looks like a good mod. How many feet of tape did you need, I see it comes in 15' rolls. Also do you recommend 1" or 2" wide wrap?

[DanHoug]

i'd bought a 25' roll of 2" and have at least 1/2 left over. you need to do a 50% overlap so 2" gives more to land on. some brands suggest soaking the stuff in water first to mold easier and quite frankly, i forgot. it puckered a bit on the sharp curves but nothing terrible, soaking would have reduced the pucker but be messier to work with. you'll need steel ty-wraps or use wire.

whatever you buy, wear gloves. it's nasty stuff that releases glass hairs like crazy.

with regard to the quantitative interior temp difference... it's 'better'. the passive heat flow out of the side vent is less and when the fan i have mounted in the vent kicks on, wired to the main fan, the air is cooler.
_________________
-dan
60% of what you find on the internet is wrong, including this post.

'87 Westy & '89 Westy both 2.1 4spd

Past projects can be found at--
www.thefixitworkshop.com

[spitsnrovers]

DanHoug - great mod and writeup!
In my mod to extract heat from the fridge flu to keep shower water warm overnight, I added fibreglass and aluminum foil. Wish I had known about the wrap you used.

My results are shown herehttp://www.griffco.ca/VW/fridgeheat.htm

Its a long story, but the last frames show the final results.
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'88 VW Westfalia
'75 Triumph Spitfire 1500

[DanHoug]

[jlrftype7]

[SSWesty]