My fridge has ice build-up in the freezer behind the inside wall. this ice is on the freezer elements, because of the buildup, the fridge is not cooling.
This sounds like a problem with the defrost circuit. It is likely that
the evaporator coil is clogged with ice due to the defrost heater / circuitry not
functioning. This can be caused by a failure of any one or more of the
1) Defrost timer. Defrost timer may be
"stuck" - failing to advance from a cooling cycle to a defrost cycle.
May be found in the toe space of many fridges, but not all.
Defrost terminator. This is a thermal sensor that is secured (usually with a clip) to the
refrigerant line close to the evaporator coil in / behind the freezer
compartment. If this component fails to detect a rising temperature, it
never allows the fridge to return to the cooling mode again.
Defroster Heating coil. This is a simple, relatively low wattage heater
secured to or near the evaporator coil. It is powered through the
defrost timer and shut off by the defrost terminator. If the coil is
burned out or otherwise "open", it will not heat to melt ice buildup on
the evaporator coil.
4) Fan. The fan is located near the
evaporator coil. If the fan is unable move air from the freezer to the
fridge, the compressor runs endlessly because cold air is not directed
into the fridge compartment
- where the thermostat is located.
Condenser coil. If the condenser has a "furry jacket" it's long overdue
for a cleaning. Gently vacuum lint / dust / dirt collected on the coil
to increase efficiency. This is probably not the problem - but it
probably needs to be done anyway.
of these steps will
require hand tools, schematics (specific to your model), electrical
test equipment, etc. Be
careful to not use sharp instruments that may puncture refrigerant
lines or electrical insulation. Allow the ice to defrost with the
fridge powered off with the freezer door opened, or place a pot of hot water
inside, hair dryer directed at the coil, etc. Access to the evaporator
coil is usually from the freezer compartment (back wall) and will
require removal of any ice maker installed.
I hope this helps!
Oct 26, 2009 |