Easy refrigerator baffle

[tlhdoc]

My gas/dc/ac refrigerator was not staying cold enough when it gets warm out.  I borrowed this idea from some other PU campers and made a new refrigerator baffle.  That (I hope) will force more air over the fins in the top compartment of the refrigerator and cause it to cool better.  The baffle that came with my PU was not wide enough force the air over the fins.

To see my mod check here http://community.webshots.com/user/tlhdoc

click on My PU Camper and go to the second page.  There are 5 pictures showing what I did.

[mike4947]

I've rarely seen a "stock" baffle work. That one should really keep the air flowing where it should.
Be prepared to eat frozen eggs for breakfast.

[tlhdoc]

Yes the eggs did freeze on the trip we just got home from.    I hope it is cold enough to freeze food in the middle of summer.  Then I will not need to install a fan.

[jstubbert]

Help me understand this baffle idea... When I look at my fridge I don't see anything that looks remotely like a baffle. There is nothing to direct airflow in the compartment other then the louvres in the compartment door cover. Maybe that is why my fridge doesn't work as well as I would hope.

I looked at the pictures and they look simple enough to construct. My qustions are:
(1) Where should the baffle be placed?
(2) What airflow am I trying to direct?
(3) Where should I be pointing that airflow?

Thanks

Jeff

[mike4947]

Jeff, unfortunately the link I have http://www.rvmobile.com/Tech/Trouble/vent.htm for pictures of the fridge baffles seems to be down. Try posting the question on PUX I'm pretty sure Chuck S. will come around with another picture source.

[tlhdoc]

The baffle is to force the fresh air into the upper compartment over the fins.  There should be a baffle in between the top and the bottom compartments of your fridge, so the air can't just go up and out the top vent without traveling through the fins.  If you check your refrigerator companies website, they should have instillation instructions that explain the baffle.  If you have any other questions let me know.

[mike4947]

Tracy, close but not quite right. The fins on the back are to get rid of heat not have heat flow over them. The baffle direct cool incoming air from the lower vent over the fins to remove the heat and direct it out the upper vent.
Here's a animated GIF http://www.dometic.com/files/UserImages/lf_absorptiondemo.gif
that shows a good example on how the fridge works.
 
In some applications you actually need two baffles. One to keep the air flowing over the fins, and a second at the top of the upper vent to force the heated air out. Otherwise you can develop a hot dead air space at the top of the fridge compartment. We've seen countertops actually bubble from being overheated by the hot air trapped above the upper vent. The frdige will work fine without the upper one if there is only a small space above the top of the upper vent to trap air.

[tlhdoc]

Mike thanks for straightening me out.   I never did and still don't really understand how the fridge works, but I know you need to force the outside air up over the fins to get the fridge to work properly.  Thanks Mike for clearing this up.   When my refrigerator was installed they put the 2 pieces of the side of the box (that was cut out for the 2 doors) in above the refrigerator so hot air can't go above the fridge.  It has to come out the top vent.  They also insulated around the fridge.

[mrflinders]

Lots of great info here.  Thanks to all.  Hopefully, I can get some insight into my issues as well.......

When I purchased my trailer in 2002, the fridge worked great.  But, in July of last year, we climbed the mountain up to Big Bear.  The drive was really long, and really slow, because is was about 110 degrees outside, and the TV was overheating.  The result was a long slow uphill climb, with the Fridge powered on in 12V mode.  
 
Once we reached the top of the hill, we headed down a bumpy dirt rode to our CG.  Once we set up camp, we noticed that the Fridge was not cold.  It seems to not work well in 12V, 120V, or LP mode.  Now, even in moderate temperatures, the Fridge gets up to 70 degrees during the day.  It seems to work, just not very well.
 
I think that I might have damaged the cooling unit by overheating it on the drive up the hill in the heat.  I took it to the coleman dealer, who told me it is working in spec.  I don't believe him because it worked 10 times better when it was new.
 
So, my questions are: Does it seem likely that I damaged the cooling unit?  If so, would improved baffling have prevented it?  And, if it is damaged, is there anything I can do?  I have been told by some to remove the fridge and flip it over a couple times to eliminate 'vapor lock'.  Does this seem like something that has a chance of working, or should I just pull the fridge and take it to Dometic for repairs?
 
Thanks for any insight you guys can offer.......
 
- Randy