Venting portable refrigerator

[andytruck]

In lieu of installing a refrigerator in the popup truck camper I am going to use my Dometic portable cooler, which is a propane fridge basically. I want to store it on a drawer slide inside a cabinet, but need to vent the propane gases.
Has anyone done something like this?
I am wondering if I can just slip a tube over the chimney flue and exit the gases outside.
I would ideally like to have a flexible hose to exhaust the gases so I can have the cooler on the seat and level it instead of leveling the entire vehicle when I make stops during the drive.
I am exploring ideas from those who have do this to make this work and safe.

 

[Ozarker]

I don't think I would put a propane burning fridge on a seat in a cab, on the floor maybe. What size is the exhaust tube and I'd only use tubing for exhausting hot gases, no rubber. How big is the fridge? Build a small leveling platform, the fridge may have leveling feet underneath to fine tune your level platform. Normal roads shouldn't be an issue, if you're climbing a mountain for 3 hours just shut the fridge off so it doesn't run at a steep angle.

 

[IdaSHO]

Dometic portable cooler, which is a propane fridge basically

Whats the model number on that?

Many of those models will do 120v/12v/LP



Also, check the owners/operating manual with regards to extending the exhaust.

Traditionally it advised to NOT do so as it adds considerable restriction to the exhaust and can potentially overheat / purge exhaust where you do not want it.

 

[Mwilliamshs]

I've never heard of a portable absorption fridge. PLEASE provide details. (model number, picture, etc)

 

[anickode]

How hot is the exhaust? SCAT and SCEET tube are rated for 550 degrees I believe. Its a silicone hose with a coiled wire a structural element. Basically dryer hose made from silicone impregnated cloth. Availabe as big or small as you want it. SCAT is single ply, SCEET is double ply. Both are very flexible and crush resistant. Not cheap, but if you just need a few feet it's a great way to go. Available from any aircraft supply house.

 

[andytruck]

It is a Dometic RC 2000. Portable cooler, and is a true three-way. Pretty cool, but I have rarely used it.
A friend gave it to me after his dad divorced and he was cleaning his mom's place.
I went another route for a fridge, so this still sits. It can be fore sale for the right price…

 

[Coachgeo]

I use to sell those as a small dometic dealer. That and PETT toilet systems. Was marketing to offroaders only. Still have one fridge about 12 years old. Only the 110v works now though Im sure I can resurect it with a lot of work.

It's basically standard 3way RV fridge just mounted to a cooler type container. It must be vented well no matter the means of power. I understand they upped the power after mine. It got HOT so the later models must get even hotter. They work by HEAT expansion of amonia/then recondinsing. The Recondensing processes absorbs the heat in the food storage space causing it to cool.

Overtime the plastic vent area at the rear melts from when used continuously especially if you keep it to close to a wall/seat orr? the 12v is intended to go to cig plug but the draw is to high for that system unless the socket is wired for heavy duty power draw. Like any 3way fridge it does not work as well when not level. At least when using LP. Not sure about if the non level affects the recondinse in all power modes or if it is only an issue when using LP heat cause the flame not hitting the heat tubes optimaly

 

[andytruck]

it is not the flame that requires level, but the chemicals inside the system. The downward flow-angle on the pipes is so slight that off-level will cause the liquid to pool in places instead of flowing down to the boiler and things will cook in the boiler.

 

[Coachgeo]

it is not the flame that requires level, but the chemicals inside the system. The downward flow-angle on the pipes is so slight that off-level will cause the liquid to pool in places instead of flowing down to the boiler and things will cook in the boiler.

Thanks for explanation....... what are the "things" that will cook in t boiler?

 

[andytruck]

From my memory… The cooling unit is made from steel, and one of the chemicals is ammonia, which rust steel pretty quick, so another chemical is an anti-corrosive one to keep the steel from rusting. The ammonia is "boiled" which causes it to float to the top of the cooling unit, where it condenses and turns back to a liquid and absorbs a lot of heat in the process, this is where the cooling action happens. It then runs back down the unit as a liquid and returns to the boiler to start over again This is s very over-simplified version to keep this short. If the ammonia pools in the pipe coils too much for too long (because the fridge is not level) then the anti-corrosive chemical, still in the boiler, will cook - it needs the liquid ammonia to mix with it to keep it from cooking. The cooked result is not unlike concrete. At first it may just be chunks or particles, but neglect may cause it to cook to the sides of the boiler. These particle float around and clog up the unit. This is why one of the fixes to a non-working unit is to flip it upside-down and back. Doing so unclogs the unit from these floaters. They are still there, and start their work clogging things up again, so this is only a temporary fix, but one that might be good enough as most campers are not used very often or very long.
A vehicle in motion sloshes the liquid around enough that is will move the chemical, but on long uphill climbs, very long climbs be aware that you may be pooling if not enough shaking is happening.
Always keep it level.