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Refrigerator TIP :
1) With summer's high humidity still hanging around, I thought
this might be a good time to discuss frost-free refrigerator
problems and their causes. If your fresh food is beginning
to warm up and you notice a coating of frost inside the freezer,
read on...
First, a bit of overview:
From the introduction of frost-free home refrigerators around
1960 up until a few years ago, defrost systems were pretty
simple. Today, many new units use 'adaptive defrost controls',
basically small computers that measure compressor run times,
door openings, and other data, to determine how often the
defrost heater should be turned on to melt accumulated
evaporator coil frost. (This defrost water then runs into a pan
under your refrigerator and quickly evaporates away)
On 'standard' systems, a small timer turns off the compressor
every 8 hours (in most ref's) that it runs, and turns on a heater
in the freezer's evaporator coil. The timer remains in the defrost
cycle for 20 minutes or so, during which a small defrost limit
thermostat turns the heater off when the coil's temperature
reaches a preset temperature. This temperature is 45-70
degrees F, depending on refrigerator design.
When the defrost system fails, it causes the evaporator coil to
continue accumulating frost until air can't get through it to do
its job of cooling (transferring heat from, actually) your
groceries.
By the time you see frost in the freezer, coating the back wall
in most designs, the coil will be clogged with frost, and in need
of attention.
First, ensure that the freezer fan's running. Fan failure can
also cause coil frost-up, so this is the first test. (Be aware that
some refrigerators have a fan switch that turns this fan off
when the freezer door's opened. And some new refrigerators'
ADC computers switch and vary the speed of the freezer fan
- these can be very tricky to diagnose).
If it's *frost* and the freezer fan's running, you have a
defrost problem, usually caused by one of 3 components: timer,
heater, or defrost t'stat. The good news is, if the frost is evenly
coating the coil, the expensive stuff's OK - no Freon leaks or
restrictions, etc. For more on this, see the second article in the
March '03 Back-issue of the DRSNews
If it's *ice* in the drain trough, that's different. ICE tells us
that defrost is taking place, but the water can't get where it
needs to go, and is refreezing. Drain freeze-ups & clogs are
pretty common, and not too tough to clear. If that's what you've
got, I'll be telling you about a little trick that'll keep it from
ever happening again. But that'll have to wait until the next
issue.
To diagnose the frost problem, slowly turn the defrost timer
clockwise with a screwdriver to click it into a defrost cycle.
The timer's located in one of several places, depending on
brand and model. Either down at floor level behind the grille,
or in the fresh food section, often behind a small plastic plug.
Occasionally I still see one with the timer mounted behind the
refrig, but (thank goodness!) that's not too common any more.
You'll recognize the timer by its 'one-way' screwdriver slot.
If the heater comes on (located in or under the coil), the timer
has stalled and should be replaced. (Watch the refrig light as
you 'click' the timer into defrost. If the heater comes on, you'll
see just a little bit of dimming of the light. A good sign!)
If no heat, it's *usually* an open defrost t'stat, a little round
device clamped to the coil outlet, with 2 wires attached. To
'prove', unplug the refrig and bypass this - just short its 2
wires together (some brands use a defrost t'stat harness plug) -
and plug it back in.
The defrost heater will come on if the t'stat was bad. 'Should
be 'closed' when cold (only). If there's frost on the coil and this
t'stat's open, it's bad.
Read the temp rating off the side of the original. You'll want to
replace it with one as close as possible to its original rating.
Most are 50 or 60F - but many newer ones are rated in Celsius
just to make life more interesting.
I rarely replace these with genuine factory parts. They're way
too pricey and not reliable enough, and the 'generics' are really
good, as well as inexpensive. Email me if you're having trouble
finding one.
I also rarely replace timers with the cheaply made factory plastic
versions. The older style, US-made Mallory timers are still
available, and I use those whenever possible; they last a whole
lot longer.
If the heater doesn't come on with the t'stat bypassed, you
probably have a bad heater (somewhat rare), but you'll need
to *prove* that. Unplug the refrig, attach a meter or test bulb
on the heater leads (leave them conn'd to the heater) and plug
back in. 120V to the heater/no heat = open heater.
This should get you started. If you're still 'stuck' with this,
again, feel free to email me with your model #, and we'll take
it from there.
PS - the best and fastest way, by far, to defrost these coils is
with hot water in a one gallon pressure sprayer and a wet-vac.
Hope to talk about that more in the near future too.
Btw, if you haven't checked out Joe Robson's great
'plain English' website for computer 'newbies' yet,
you're in for a treat! (Even if you've been around
computers for a long time like I have, you'll learn a lot
from Joe. I pickup a new tip or two every time I visit!):
The Newbieclub
2) From the Food for Thought Dept: 'Growing Good Corn'
There was a farmer who grew award-winning corn. Each year
he entered his corn in the state fair where it won a blue ribbon.
One year a newspaper reporter interviewed him and learned
something interesting about how he grew it.
The reporter discovered that the farmer shared his seed corn
with his neighbors. "How can you afford to share your best
seed corn with your neighbors when they are entering corn in
competition with yours each year?" the reporter asked.
"Why sir," said the farmer, "didn't you know? The wind
picks
up pollen from the ripening corn and swirls it from field to
field. If my neighbors grow inferior corn, cross-pollination
will steadily degrade the quality of my corn. If I am to grow
good corn, I must help my neighbors grow good corn."
He is very much aware of the connectedness of life. His corn
cannot improve unless his neighbor's corn also improves.
So it is in other dimensions. Those who choose to be at peace
must help their neighbors to be at peace. Those who choose to
live well must help others to live well, for the value of a life is
measured by the lives it touches. And those who choose to be
happy must help others to find happiness, for the welfare of
each is bound up with the welfare of all.
The lesson for each of us is this: if we are to grow good corn,
we must help our neighbors grow good corn. - Author unknown
3) Here's a tip that has worked out pretty well for us. Not
exactly related to appliance repair, but one of those good
ones I like to pass along:
How do I get that stain out of my couch? Commercial
upholstery shampoos do a good job and are easy to use,
but if you'd like to do it yourself (and I know you would!)
you can make a homemade preparation using liquid dish
detergent and warm water. You just whip it with a hand mixer.
After testing it on an unnoticeable area, apply dry suds by
lightly scrubbing with a cloth or soft brush.
Shampoo only a small area at a time and use a spatula or
rubber scraper to lift off dirty suds. (I use my wetvac - what
else!) - from the DoItYourself.com newsletter, 6-25-04
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