Maybe I should explain this.
Your fridge will have EITHER:
a) if it's an older fridge, an electric "mullion heater", or
b) in a newer fridge, something commonly referred to as a "Yoder loop"
.. under the narrow panel on the front of the fridge between the fresh
food and frozen food compartment doors.
As mentioned previously, the purpose of both the mullion heater and the
Yoder loop is to warm that narrow panel to prevent condensation from
forming on it.
If the panel is warmed by a mullion heater, you should find an "Energy
Saver" switch on the fridge somewhere which simply turns that mullion
That's because in dryer climates, like you have in the prairies, you
don't get any condensation forming on that panel anyway, so why pay for
electricity to heat that panel to prevent condensation that won't form
A "Yoder loop" is where they take the condenser tubing (the black steel
tubing at the back of the fridge where the hot compressed refrigerant
gas cools down) and run that tubing around the side of the fridge to the
front and then under that narrow panel between the fresh and frozen food
compartment doors. If you have a Yoder loop, there's no way to turn it
off or prevent that area from getting warm except by unplugging the
Typically, in a frost free fridge there will be two simultaneous air
currents with the evaporator fan driving both of them:
In the frozen food compartment, air will be drawn into the space between
the fresh and frozen food compartments through vents near the front of
the frozen food compartment floor. In the fresh food compartment, air
will be drawn into the space between the two food compartments through
vents near the front of the fresh food compartment ceiling.
The combined air stream will then be sucked by the evaporator fan to the
the rear of the fridge where the air will be blown over the evaporator
coils. Some frost free fridges have the evaporator coils in the space
between the fresh and frozen food compartments. Most of the cold air
coming off the evaporator coil will be blown into the frozen food
compartment, but some of it will be blown into the fresh food
Then, each of those air currents ends up drifting to the front of the
fridge near the space between the fresh and frozen food compartments
where the air gets sucked back into those vents and gets drawn to the
back of the fridge through that space between the two compartments and
into the evaporator fan again.
It's just the fact that most of the cold air gets blown into the frozen
food compartment that results in the freezer being colder than the
"fridge", although some fridges have an adjustable baffle that allows
the user to increase or decrease the cold air flow into the fresh food
compartment, with the rest of the cold air being blown into the frozen
Now, my understanding of those air ducts that GFretwell was describing
is that those are to carry the cold air being blown into the fresh food
compartment down to the bottom of the fresh food compartment. By
blowing that cold air in near the bottom of the fresh food compartment,
and drawing air back into the evaporator fan at the top of the fresh
food compartment, you establish a cold air current that sweeps through
the whole volume of the fresh food compartment keeps it at a uniformly
cold temperature everywhere.
If the cold air entering the fresh food compartment were to be blown in
near the top, that cold air would take the shortest straightest path to
get sucked back into the evaporator fan, which is just across the
ceiling of the fresh food compartment. The result would be that the
fresh food compartment would be very cold at the top, but everything
below that cold air current along the ceiling of the fresh food
compartment wouldn't be very cold at all.
The crisper trays are out of the path of cold air circulation in the
fresh food compartment, and only get cooled by the sinking of cold air
to the bottom of the fresh food compartment.
PS: Talking about the panels on the outside feeling warm...
CHEST style freezers will feel warm over most of the outside of the
freezer. That's because in chest style freezers, the insulation is in
the walls of the freezer, with the evaporator coils on the interior side
of that insulation and the condenser coils on the exterior side of that
insulation. So the heat released from the condenser coils in a chest
style freezer dissipate through the side walls of the freezer, keeping
those side walls warm. Next time you're in a supermarket, feel the
outside walls of the open top chest style freezers, and you'll find that