Hi All,

Fridge - Kenmore/GE 12 years old. Freezer on top.

My fridge was acting strange temp-wise, so I pulled the panel in the freezer
and found the coil all frosted up. Defrosted it.

Now to the problem, as to why it happened. Pulled the defrost timer and
found one crimped wire a bit loose. Soldered it.
Did continuity test on the defrost heater - OK. The defrost thermostat
contact was open, which was at 60deg - OK too.
Put it all back together. Fridge works, but...

After about a 24hr run, I'd like to verify that the defrost works. The
timer motor is turning, I can see that with the control cover off. But can
I really tell if the defrost heater is working? Should the back panel in
the freezer be warmer? This would verify the whole ckt.

RichK

RichK wrote:
Hi All,

Fridge - Kenmore/GE 12 years old. Freezer on top.

My fridge was acting strange temp-wise, so I pulled the panel in the freezer
and found the coil all frosted up. Defrosted it.

Now to the problem, as to why it happened. Pulled the defrost timer and
found one crimped wire a bit loose. Soldered it.
Did continuity test on the defrost heater - OK. The defrost thermostat
contact was open, which was at 60deg - OK too.
Put it all back together. Fridge works, but...

After about a 24hr run, I'd like to verify that the defrost works. The
timer motor is turning, I can see that with the control cover off. But can
I really tell if the defrost heater is working? Should the back panel in
the freezer be warmer? This would verify the whole ckt.

RichK



A clamp-on ammeter on the switched lead from the defrost timer to the
heater ought to tell you.

HTH,

Jeff

--
Jeffry Wisnia

(W1BSV + Brass Rat '57 EE)

"Truth exists; only falsehood has to be invented."

Of course, the defrost lead will only be drawing amperage if the bimetal is
cold enough. But, that confuses things.

--

Christopher A. Young
You can't shout down a troll.
You have to starve them.
..

"Jeff Wisnia" wrote in message
...
RichK wrote:
Hi All,

Fridge - Kenmore/GE 12 years old. Freezer on top.

My fridge was acting strange temp-wise, so I pulled the panel in the
freezer
and found the coil all frosted up. Defrosted it.

Now to the problem, as to why it happened. Pulled the defrost timer and
found one crimped wire a bit loose. Soldered it.
Did continuity test on the defrost heater - OK. The defrost thermostat
contact was open, which was at 60deg - OK too.
Put it all back together. Fridge works, but...

After about a 24hr run, I'd like to verify that the defrost works. The
timer motor is turning, I can see that with the control cover off. But
can
I really tell if the defrost heater is working? Should the back panel in
the freezer be warmer? This would verify the whole ckt.

RichK



A clamp-on ammeter on the switched lead from the defrost timer to the
heater ought to tell you.

HTH,

Jeff

--
Jeffry Wisnia

(W1BSV + Brass Rat '57 EE)

"Truth exists; only falsehood has to be invented."

"Stormin Mormon"

Of course, the defrost lead will only be drawing amperage if the bimetal
is
cold enough. But, that confuses things.

I have thought about the clamp on meter, after I posted it. Tried to feel
the plastic cover in the freezer, but it's not good enough indication. It
seems that the bottom of the back panel is a bit warmer, which is where the
heater is.

Why do you say that it confues things? It seems like the only good test, I
can think of.

Rich

RichK wrote:
"Stormin Mormon"


Of course, the defrost lead will only be drawing amperage if the bimetal

is

cold enough. But, that confuses things.


I have thought about the clamp on meter, after I posted it. Tried to feel
the plastic cover in the freezer, but it's not good enough indication. It
seems that the bottom of the back panel is a bit warmer, which is where the
heater is.

Why do you say that it confues things? It seems like the only good test, I
can think of.

Rich



It *should* work, particularly if you have one of the motor driven
defrost timers which has a manual knob on it which allows you to advance
the timer by hand so that you don't have to stay there for a day
watching the meter waiting for the defrost time to come up. G.

I suppose if you were anal enough about it you could use a slow speed
chart recorder to plot the output from a current transformer placed on
that lead to see that current comes on periodically and stays on until
the thermostat ("bimetal") senses that the evaporator area isn't ice
cold anymore and opens the circuit.

Jeff (Don't take me seriously please.)

--
Jeffry Wisnia

(W1BSV + Brass Rat '57 EE)

"Truth exists; only falsehood has to be invented."

"Jeff Wisnia"


It *should* work, particularly if you have one of the motor driven
defrost timers which has a manual knob on it which allows you to advance
the timer by hand so that you don't have to stay there for a day
watching the meter waiting for the defrost time to come up. G.

There are some clear advantages to old tech designgs. The timer can be
advanced using a screwdriver to rotate the cam operating the contacts.

I suppose if you were anal enough about it you could use a slow speed
chart recorder to plot the output from a current transformer placed on
that lead to see that current comes on periodically and stays on until
the thermostat ("bimetal") senses that the evaporator area isn't ice
cold anymore and opens the circuit.

No I did not take this part seriously :-) Don't have a chart recorder :-)
But was going to ask, if anyone has seen something in that line. I'd like
to record somehow, the total time an appliance runs in 24hrs - say the
refrigerator in question. Of course you can sit through several cycles with
a stopwatch and record the times.

Rich

On Thu, 22 Dec 2005 15:03:47 -0500, Jeff Wisnia
wrote:

RichK wrote:
Hi All,

Fridge - Kenmore/GE 12 years old. Freezer on top.

My fridge was acting strange temp-wise, so I pulled the panel in the freezer
and found the coil all frosted up. Defrosted it.

Now to the problem, as to why it happened. Pulled the defrost timer and
found one crimped wire a bit loose. Soldered it.
Did continuity test on the defrost heater - OK. The defrost thermostat
contact was open, which was at 60deg - OK too.
Put it all back together. Fridge works, but...

After about a 24hr run, I'd like to verify that the defrost works. The
timer motor is turning, I can see that with the control cover off. But can
I really tell if the defrost heater is working? Should the back panel in
the freezer be warmer? This would verify the whole ckt.

RichK



A clamp-on ammeter on the switched lead from the defrost timer to the
heater ought to tell you.

Doesn't this thing have slide on connectors? Why not putting the
ammeter right in the circuit? Most people don't have a clamp-on.

HTH,

Jeff


Remove NOPSAM to email me. Please let
me know if you have posted also.

"mm" wrote in message

Doesn't this thing have slide on connectors? Why not putting the
ammeter right in the circuit? Most people don't have a clamp-on.

Actually, you're right. There's a connector that plugs onto the timer and
another one near the Temp Control. Could have allowed the freezer to cool
and close the defrost thermo, then checked continuity of the whole ckt
downstream from that plug.

As it is, I had a clamp-on attachment for a multimeter and this was an
excuse to use it. Also made me aware how much current is used.

Rich

On Thu, 22 Dec 2005 22:54:02 -0500, "RichK" wrote:


As it is, I had a clamp-on attachment for a multimeter and this was an
excuse to use it

I understand that fully, and do the same thing.

.. Also made me aware how much current is used.

Rich



Remove NOPSAM to email me. Please let
me know if you have posted also.

RichK wrote:

Hi All,

Fridge - Kenmore/GE 12 years old. Freezer on top.

My fridge was acting strange temp-wise, so I pulled the panel in the freezer
and found the coil all frosted up. Defrosted it.

Now to the problem, as to why it happened. Pulled the defrost timer and
found one crimped wire a bit loose. Soldered it.
Did continuity test on the defrost heater - OK. The defrost thermostat
contact was open, which was at 60deg - OK too.
Put it all back together. Fridge works, but...

After about a 24hr run, I'd like to verify that the defrost works. The
timer motor is turning, I can see that with the control cover off. But can
I really tell if the defrost heater is working? Should the back panel in
the freezer be warmer? This would verify the whole ckt. RichK


They are easy to check out. If it is your fridge, let it run a few hours
and while the fridge is running advance the timer until it clicks into
defrost mode.
The evaporator fan should stop, wait a few minutes and open the freezer
door and feel where the heater coil is located, it should be warm.
You will usually get a clear indication that the element is heating.

If it isn't heating immediately unplug the fridge and check for
continuity through the defrost termination thermostat circuit, it should
be closed, if not and all the other circuits test okay, replace the
defrost TH with one of the same termination temp. Check out the wiring
diagram and schematic for check points.
- udarrell

--
PROPER A/C UNIT & DUCT SIZING ESSENTIAL for EFFICIENCY & BTUH PERFORMANCE
http://www.udarrell.com/proper_cfm_b...syste ms.html

"udarrell"


They are easy to check out. If it is your fridge, let it run a few hours
and while the fridge is running advance the timer until it clicks into
defrost mode.
The evaporator fan should stop, wait a few minutes and open the freezer
door and feel where the heater coil is located, it should be warm.
You will usually get a clear indication that the element is heating.

You are right. The key here is to feel the heater area, soon after you
force the defrost cycle. I could feel that part of the of panel warmer in
the freezer. I also measured the current - it was 4A.

Left the defrost cycle on for a while and the thermostat must have worked,
as the panel got cool again. I probably would have cycled ON/OFF during the
40min (spec) that the cycle runs.

I later measured the run current of the compressor in the same place in a
circuit (a common leg) and to my surprise it was only 2A. Is this about
right?

The compressor spec (from sheet on the back of fridge) is 1092 BTU/hr.
Monthly energy consumption listed at 80 KWH.with 20-30% run time at 70F.

Rich

This is Turtle.

first the 40 minute cycle you speak of is new to me for the longest
defrost cycle time that i have ever hear of is the 31 minute every 8
hours , but most are the 25 minute every 6 hours.

now if the defrost circuit is pulling 4 amps in defrost cycle. it is
running and pulling the right amps. if it is pulling 4 amps your heater
is running. Your good there.

most Refrigerator these days will pull 1.5 amps to 3.5 amps and most
regular refrigerator will pull between 1.5 and 2.5 amps. So your 2 amps
seem just about right.

now in your other post you spoke of a loose spade connection and not a
broken connection. Was this connection broken enough to say it could
break the power to that section or not ? we are looking for a cause for
the defrost system to stop and have not found one yet. So now your
going to have to watch it and try to determine the cause of the defrost
system to stop working. here is a list item or causes that would stop
the defrost system from working.

Defrost time just hang up and stop running.

Malfuctioning Defrost terminator hanging up and sometime works or other
times not work.

Defrost elements is defective or loose connection at the tie in at the
elements for the wire to connect.

=============================================

Now what i have heard so far it is working good now but if it messes up
it will not show up as a problem for 7 to 14 days and you will see it
freeze up again. now this might be the best cource of action here
because of tring to do all the testing to see a refrigerator running
good. wait 14 days to see if it screws up again.

=============================================

Now here is what I think and really off the record here. I think the
defrost timer stop on you and when you moved it it unstuck it and went
back to working. If it is frose up the heater will most of the time
will not be enough to do a total recovery from the start of it all
froze up.

TURTLE

Hi Turtle,

Thanks for confirming my measurements!

"TURTLE" wrote in message

first the 40 minute cycle you speak of is new to me for the longest
defrost cycle time that i have ever hear of is the 31 minute every 8
hours , but most are the 25 minute every 6 hours.

I have not measured the defrost cycle. I'm quoting from the wiring diagram
and info that was on the back of the fridge. It states: Defrost Control 12
hrs. @ 40 min. Defrost Thermostat 60-28degF.
But it was at least 30 min, just from what I remember.

now if the defrost circuit is pulling 4 amps in defrost cycle. it is
running and pulling the right amps. if it is pulling 4 amps your heater
is running. Your good there.

OK.

most Refrigerator these days will pull 1.5 amps to 3.5 amps and most
regular refrigerator will pull between 1.5 and 2.5 amps. So your 2 amps
seem just about right.
OK

now in your other post you spoke of a loose spade connection and not a
broken connection. Was this connection broken enough to say it could
break the power to that section or not ?

The "loose spade" I found was the power to the timer coil. There's a "post"
wire, which is crimped to the spade connector. It is that crimp that was
loose. The timer motor wires are like human hair and are wrapped and
soldered to that "post wire".

I found the loose connection as I was measuring timer motor resistance. The
measurement was varying, due to the post moving.

FWIW, I also found a spot on the plastic timer cam, where there was some
melting of plastic. Suspect the motor stopped and contacts did not break
cleanly and perhaps "cooked" for a while.
I cleaned up the cam and put it back in. Cleaned up the contacts in the
timer. They break the full load of the compressor, which is about 2A as
you've confirmed.

=============================================

Now what i have heard so far it is working good now but if it messes up
it will not show up as a problem for 7 to 14 days and you will see it
freeze up again. now this might be the best cource of action here
because of tring to do all the testing to see a refrigerator running
good. wait 14 days to see if it screws up again.

=============================================

Will watch for a while. After a few days, I will pull the panel in the
freezer and see how much frost has accumulated on the coil, if any.

Now here is what I think and really off the record here. I think the
defrost timer stop on you and when you moved it it unstuck it and went
back to working. If it is frose up the heater will most of the time
will not be enough to do a total recovery from the start of it all
froze up.

You got it! I wrote that above.

Thanks for your help. I've been able to troubleshoot several things in the
house, thanks to the help from this Group.

Regards,

Rich

This is Turtle.

There is one thing i left out. In the refrigerator service business
there is a old rule that says if there is a dought as to what the
problem was with the defrost system. As a rule you change the defrost
timer and move on.

TURTLE

Three easy ways to tell if it is working.
1. put it in the defrost cycle and look at the heater, it will turn red.
Even the metal heaters turn red.
2. Wait for the defrosting to begin. You'll hear the water dripping on the
heater, water should show up in the drip pan.
3. Put it into defrost and put the plug in and out of the wall outlet. If
it's working you'll see a pretty good spark.








"RichK" wrote in message
news
Hi All,

Fridge - Kenmore/GE 12 years old. Freezer on top.

My fridge was acting strange temp-wise, so I pulled the panel in the
freezer
and found the coil all frosted up. Defrosted it.

Now to the problem, as to why it happened. Pulled the defrost timer and
found one crimped wire a bit loose. Soldered it.
Did continuity test on the defrost heater - OK. The defrost thermostat
contact was open, which was at 60deg - OK too.
Put it all back together. Fridge works, but...

After about a 24hr run, I'd like to verify that the defrost works. The
timer motor is turning, I can see that with the control cover off. But
can
I really tell if the defrost heater is working? Should the back panel in
the freezer be warmer? This would verify the whole ckt.

RichK

RichK wrote:
Hi All,

Fridge - Kenmore/GE 12 years old. Freezer on top.

My fridge was acting strange temp-wise, so I pulled the panel in the freezer
and found the coil all frosted up. Defrosted it.

Now to the problem, as to why it happened. Pulled the defrost timer and
found one crimped wire a bit loose. Soldered it.
Did continuity test on the defrost heater - OK. The defrost thermostat
contact was open, which was at 60deg - OK too.
Put it all back together. Fridge works, but...

After about a 24hr run, I'd like to verify that the defrost works. The
timer motor is turning, I can see that with the control cover off. But can
I really tell if the defrost heater is working? Should the back panel in
the freezer be warmer? This would verify the whole ckt.

RichK


Hi,
If the contacts on the timer is badly pitted, just replace it for peace
of mind.
Tony

"Tony Hwang"

If the contacts on the timer is badly pitted, just replace it for peace
of mind.
Tony

The contacts were pitted, but no more than nay other relay contacts I have
seen. Smoothed them with a small file for now. There was still a fair
amount of contact material left.

I know that some relay contacts in the higher rating are made of
silver-cadmium oxide, which is closer to the surface. Once the cad-oxide is
worn, the contacts wear out much faster.

Since this is my own fridge, I can take the risk and keep that timer working
for longer. For now it's fine. If I were doing it for someone else, I'd
replace the timer.

Rich