Sunday, June 26, 2011

Keeping the Refrigerator Cold



Keeping the contents of your refrigerator safely cold (the ideal
temperature is around 37° F.) can be tough, especially in hot
weather. The absorption-type Dometic or Norcold refrigerator used in
your Lazy Daze doesn't cool as fast as the compressor-type unit in
your house, and it's subjected to much greater temperature
fluctuations...so your rig's fridge needs special care if it is to
do its job well. Here are some tips to help you get the best
performance from your RV's refrigerator.

PRE-COOL

If possible, start up the fridge the night before you leave on a
trip, giving it plenty of time to cool down. It can take 12-24 hours
for an RV fridge to reach its optimum temperature, so the more of a
head start you give it, the better.

PRELOAD

Before a trip, freeze a bunch of "Blue Ice" or similar freezable
packs in your freezer at home...then transfer them to the RV's
fridge to jump-start the cooling process.

FILL 'ER UP

You might think that having more stuff in the fridge would make it
work harder, but in the long run the opposite is true: packing the
shelves really helps keep things cold. Think of it this way: any
mass stored inside the fridge--especially water--will "store up
cold" during the night, and then help to retain low temperatures
during the day when the outside temperature is high. A half-empty
fridge experiences much bigger temperature swings than one that is
full. Just loading the unused space with bottles of water made a
huge difference in my old Dometic's ability to maintain a cool
temperature throughout the day when I was in Arizona. So pack those
shelves!

PUT COLD WHERE YOU NEED IT

Speaking of packing shelves, that goes double for your freezer: fill
it up with a mix of food and "Blue Ice" type freezable packs. Not
only will it help keep temperatures down, but if you need to turn
off the fridge (if you prefer to shut it off while driving, for
example), you can transfer the ice packs from the freezer to the
refrigerator section to keep that part safely chilled. Put them back
in the freezer to refreeze overnight.

KEEP THE AIR MOVING

It's important to keep air circulating inside the refrigerator, so
that warm and cold spots don't form. Otherwise you could end up with
spoiled meat and frozen lettuce, even when the "average" temperature
is close to ideal. Buy a Valterra FridgeCOOL--a tiny fan that runs
for weeks on a pair of "D" batteries--and put it on a bottom shelf
where it will help keep the air moving around. It's Camping World
item #6675, and only costs about $17.

Another approach is to insall a small 12-volt fan wired across the interior
light switch contacts. The interior light acts as a dropping resistor,
slowing the fan down and reducing the current draw to a very low level.
It isn't super powerful but provides enough circulation to keep the thermal
layers broken up. A couple of zip-ties will keep it in place. For some photo
details, see
http://www.flickr.com/photos/lwade/sets/72157602104742183/
KEEP THE AIR MOVING, PART 2
Something most people don't think about is the heat-exchanger coils
on the back of the refrigerator. But they perform a crucial
function: all the heat that your fridge sucks out of its interior
has to be transferred to the outside air via these coils. If they
don't have good air circulation to carry away that heat, your fridge
won't be able to do its job. That's why there is a vent on top of
your rig above the fridge: to let the hot air escape. But how about
giving it a little help? It's easy to install a solar-powered
Valterra Solar Exhaust Fan under that vent, with a tiny solar panel
that powers it independently of your rig's electrical system. One of
these can make a big difference in hot weather. It's Camping World
item #19710, and costs about $40.

Installing Muffin Fans To Cool The Refrigerator


DON'T OPEN THE DOOR TO CHECK THE TEMPERATURE

Instead, buy an inexpensive (as little as $10) digital
indoor-outdoor thermometer and put its sensor in the fridge, with
the digital readout stuck to the door. Now you can tell how things
are doing without opening the door! Don't worry about the
cable--it's thin enough to snake through the door gasket without
causing any air leaks.


Contributors: Andy Baird, Larry Wade, Don Malpas

Revised 22 Jul 2011