Any appliance repair experts out there? I have a bad defrost thermostat on
a magic chef fridge. I was wondering if I can use a defrost thermostat off
of a similar GE fridge. they work by opening and closing based on temperatu
re so I dont see why they wouldnt be interchangeable.
On Tuesday, September 3, 2013 7:44:50 PM UTC-5, Jdog wrote:
f of a similar GE fridge. they work by opening and closing based on tempera
ture so I dont see why they wouldnt be interchangeable. Any ideas?
Any good appl;iance repair parts store should be able to cross-reference pa
rts. The exact temperature setting might be stamped on the thermostat. Bu
t, I would be skeptical of just blindly replacing one brand with another as
you don't know exactly what the manufacturer considers the correct tempera
ture for defrosting. Obviously the temp has to get above 32F, but one manu
facturer might use a 40F thermostat, while another uses 45F to get the job
Hmm. This is a learning moment for me. So, please
tell me and the rest of the class how a higher
temp cut off of the termination stat makes the
coil defrost faster? I'll admit, I sure don't
see it from here.
Christopher A. Young
Learn about Jesus
On 9/3/2013 9:28 PM, firstname.lastname@example.org wrote:
temperature setting might be stamped on the
thermostat. But, I would be skeptical of just
blindly replacing one brand with another as you
don't know exactly what the manufacturer considers
the correct temperature for defrosting. Obviously
the temp has to get above 32F, but one manufacturer
might use a 40F thermostat, while another uses
45F to get the job done faster.
My aunt Myrtle heard it from the hair dresser, who heard
it directly from a CIA guy who used to work for.... so
it has to be true!
Christopher A. Young
Learn about Jesus
On 9/4/2013 5:50 AM, The Daring Dufas wrote:
If the thermostat is located near the heater, it may kick off before the
rest of the house warms up. Turning the thermostat up higher than
needed will help to overcome this thermal inertia, permitting more heat
to reach the rest of the house in one heating cycle than it would have
if the thermostat has to cycle several times.
Most sane installers place the thermostat near the air return as is
required. The point I was making is that many folks believe that setting
the thermostat way past the desired temperature that it will
cool or heat faster as though the control knob is like the accelerator
pedal in an automobile. ^_^
Not necessarily, I've had to deal with a lot of women who find
technology to be a mysterious, scary and magical concept that should
only be dealt with by properly trained shamans. I don't fault them for
their ignorance of technology because they may know many things that I
am quite ignorant of but damn! How can somebody be that dumb?! O_o
On Wednesday, September 4, 2013 2:12:56 PM UTC-4, The Daring Dufas wrote:
And certainly they don't put it where the heat comes out.
The point I was making is that many folks believe that setting
Yep, I know exactly what you mean. They think it puts out
more BTUs the higher it's set. The only place it could have
some effect is in HVAC where it's multi-stage. If you set
it up say 1 deg, it might come on at low stage, where if it
were set at 5 deg higher, it would be high stage, so it would
be putting out more heat or cooling. But I have a Honeywell VisionPro ther
mostat on a 2 stage furnace and the only time
it's on low stage is when it's maintaining the temp. If I
kick up the thermostat even 1 deg, I've never seen it stay
at low stage, it goes to high.
On 9/8/2013 2:49 PM, email@example.com wrote:
Darn, I forgot about the two stage heating and cooling. I run across so
few of them in the area but have installed and serviced the variable
speed systems. The HVAC supply houses were selling residential dual
staged compressor condensing units at one time but those types seem to
have fallen out of favor for the newer variable speed units. Many of the
commercial rooftop systems I've serviced and installed have dual
compressors that are staged but it's rare to see one on a home. I've
never serviced or installed a two stage heating system here in my area
unless you think of a heat pump with backup heat as one. I suppose the
staged gas furnace heating systems are more useful in colder climates. ^_^
The temperature at which the DTS opens to cut off power to the defrost
heater won't affect the rate at which the evaporator coil defrosts.
That's determined entirely by how big your defrost heater is, and how
many of them you have. Most fridges have one, some have two. The cut
off temperature of the DTS only comes into play after the evaporator
coil is fully defrosted and it's temperature starts to rise above 32
Where you need different temperature settings on the DTS is for
different evaporator coil designs. Aluminum is a good conductor of
heat, but because of the length of the evaporator coil, you could have a
dozen or so degrees difference in temperature between one end and the
other, or from the side closest to the defrost heater to the side
furthest. Having the DTS shut off power to the defrost heater at 45 deg
F instead of 35 deg. F helps to ensure the entire evaporator is fully
defrosted before you shut off the defrost heater.
So for an evaporator coil that doesn't have internal metal supports to
conduct heat horizontally and vertically between different sections of
the coil, you'd need a higher cut off temperature so that you'd be sure
the entire coil was defrosted before the DTS cut power to the defrost
heater. On a smaller coil with metal supports between various sections
of the coil that could conduct heat everywhere throughout the coil, you
wouldn't have as large a temperature difference between one part of the
coil and another, so there you could use a DTS with a lower cut off
temperature and still be sure the entire coil was defrosted.
So, the original poster could use a DTS with a cut off temperature of 50
degrees F, say, and be sure his entire coil was defrosted with every
defrost cycle. All it would mean is that the overall energy efficiency
of the fridge would go down a bit because the defrost heater would stay
on until the aluminum evaporator coil was unnecessarily warm. So, it
would add a few kilowatts to his electricty bill at the end of each
month, meaning that it would cost a few bucks more each month to operate
But, IN ALL CASES, the DTS allows full power to the defrost heater until
it senses a temperature rize in the aluminum coil above freezing. So,
there's no temperature CONTROL of the defrost heater whatsoever... it's
either red hot or cold as a cucumber, and nothing in between.
So, after the DTS cuts off power to the defrost heater, the fridge just
sits there on it's coffee break until the defrost timer finishes the
defrost cycle and diverts electrical power back to the fridge's cold
control, and the cold control decides whether or not to turn the
compressor and evaporator fan on to cool the fridge down.
For those that don't know, the DTS shuts off power to the defrost heater
in the simplest possible way. It's simply wired in series with the
defrost heater. So once the DTS opens in response to the temperature
rising above freezing, the circuit to the defrost heater is interrupted
and no power can flow to the defrost heater.
Everything in the world is incomprehensible until you understand it.
Then, it's simple as mud.
Yes you should be able to.
Be advised that a defrost thermostat is now officially called a DTS, or
Defrost Termination Switch. That's because the operation of the device
is more similar to that of a switch than that of a thermostat. A
thermostat CONTROLS the temperature, trying to maintain it at a certain
set point, whereas a switch doesn't, and DTS's don't do any controlling
at all, so genetically, they're more closely related to switches than
Also be aware that every different model of DTS actually has two
temperature switching points.
The DTS will typically open, thereby breaking the circuit to the defrost
heater at a temperature between 32 to 45 degrees Fahrenheit, but then
the DTS will remain open until the defrost cycle is over, the compressor
comes back on and the temperature of the evaporator coil drops back down
to below 20 degrees Fahrenheit. The DTS then closes so that it will be
ready to allow current flow to the defrost heater come the next defrost
cycle. If you didn't have that 20 degree difference in there, then
you'd run into problems with the defrost heater going on and going off
repeatedly when the temperature was right around the temperature where
the DTS opens, and the DTS would go nutz turning the defrost heater on
and off cuz it can't make up it's mind what to do right AT that
So, probably any DTS would work, but I'd try to get one that had the
same open and closed temperatures as the Magic Chef fridge did.
If the Magic Chef DTS isn't available, there SHOULD be a recommended
replacement DTS listed.
But, I agree with you. Any DTS that opens just above the freezing point
and closes again once you're well below the freezing point SHOULD work
reasonably well. I think the only reason you'd want to go with one that
had the same tripping temperatures is because those temperatures worked
fine when they were testing the fridge before it went into production,
so those same temperatures should work equally well regardless of who's
DTS you use.
of a similar GE fridge. they work by opening and closing based on
temperature so I dont see why they wouldnt be interchangeable.
Since it's only for the defrost part of the fridge, I'd try it, as long
as the wiring matches and the thing can be mounted. The worst thing
that will happen is that the fridge wont defrost.
Of course an identical replacement part would be the best solution, but
parts like that can be outrageously costly. I'd call an appliance parts
house and ask the price, then go from there!
Different brands and models have different
temperature settings. But, overall, they are
not fussy. I'd go ahead and try it. Should
Christopher A. Young
Learn about Jesus
On 9/3/2013 8:44 PM, Jdog wrote:
I was wondering if I can use a defrost thermostat
off of a similar GE fridge. they work by opening
and closing based on temperature so I dont see
why they wouldnt be interchangeable.
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