Old & new refers

[Borrego Dave]

A neighbor and I were talking about RV refers and how close they need to be to level. I've read many posts of the difference of the older units to newer ones. My question is roughly when did the design of them change? Also mentioned is the shape difference between them, does anyone have any pics of that?

[The Minimalist]

In the case of absorption refrigerators, it's not a question of old or new. Off level operation of an absorption unit can cause overheating in the boiler which reduces efficiency. Also, if you continue to operate the unit in this overheated condition the sodium chromate, a corrosion inhibitor, can crystalize in the tubes blocking the system.

You may be referring to absorption refrigerators (old) to some of the 12 volt units (new) which operate on the same principle as your home refrigerator where leveling is not as critical.

[Bob Miller]

In RV refrigerators there is nothing intrinsically "OLD" about absorption refrigerators. They are still the standard of the RV industry and 10's of thousands of them are installed in new RV's every year.


In Dometic Units it's easy peasy to tell the difference between early and late style.


If the boiler cover has square edges it's an early unit and has to be operated in as level a condition as possible.


If it has a curved boiler cover it's the later design and "Reasonably Level" is all that's required.

[Borrego Dave]

Thanks Bob, that's what I've read. Just wondered when/year they made the design change to them. Just a FYI thing.

[mbbear]

Originally Posted by Bob Miller

In RV refrigerators there is nothing intrinsically "OLD" about absorption refrigerators. They are still the standard of the RV industry and 10's of thousands of them are installed in new RV's every year.


In Dometic Units it's easy peasy to tell the difference between early and late style.


If the boiler cover has square edges it's an early unit and has to be operated in as level a condition as possible.


If it has a curved boiler cover it's the later design and "Reasonably Level" is all that's required.

Ive got a question for you. Recently I spoke with a gentleman who was selling a unit that had refrigerator that was propane or 110v only, no 12v. I asked him what he did while traveling and he responded that he just let it run while driving. I wonder if this is usual? I seems to me that the level of the camper would be changing as you drive. Will this affect it? Thanks

[Borrego Dave]

Originally Posted by mbbear

Ive got a question for you. Recently I spoke with a gentleman who was selling a unit that had refrigerator that was propane or 110v only, no 12v. I asked him what he did while traveling and he responded that he just let it run while driving. I wonder if this is usual? I seems to me that the level of the camper would be changing as you drive. Will this affect it? Thanks

A lot of folks run their refers on LP while traveling. There is no problem with it not being level as the trailer moves around so much there is not enough time for overheating to happen and cause a blockage in the system. Been doing that for over 30 years with no problem, even with the older units that were more susceptible to out of level conditions. So the answer is no, it won't hurt the refer. Post 2 gives a good example of what happens with older units.

[Alf S.]

Originally Posted by Borrego Dave

Thanks Bob, that's what I've read. Just wondered when/year they made the design change to them. Just a FYI thing.

Hi: Borrego Dave... One or two other design changes in the recent past at least with the Dometic refer. Our 2007 5 cu. ft. fridge had an internal drain pan that you had to remove from the unit and pour off the defrost water. Our 2014 6.9 cu. ft. model has an exterior drain tube so the defrost water runs out the back of the fridge into an evap. cup.
Our 2007 5.0 cu. ft. model had to be manually changed from one power source to the other. The 2014 6.9 cu. ft model has an Auto-electronic change over system to select its own optimum power source.
These changes have occurred in the last 7 years, and I'm not convinced they are all for the better.
Alf S. North shore of Lake Erie

[Borrego Dave]

Interesting info Alf, I don't think I've ever had any water drainage. Might have and not noticed it though as I pretty much camp out in the desert and with the heat....next time I'm out I'll check that.
I did some checking on line and did find the difference in the boiler design of the older and newer refers as far as the change they made for leveling.