How do you know the defrost heater is good? From what I can determine the defrost heater is part of the evaporator coil?

Hi, I'm experiencing the same symtoms with my Samsung side by side model RS2556SH.

I have tested the heater, the thermistor, and the thermo-switch. Everything tests according to the readings specified in this thread. The unit is freezing up within a couple of weeks of defrosting.

The repair man suggested it could be the drain heater. Is this possible? Is there even a drain heater?

Everything seems to work. Am I down to a circuit board or something?

Fan works

What else could it be?

One (1) Year Parts and Labor on Refrigerator and Homepad Terminal
Five (5) Years Parts and Labor on Sealed Refrigeration System Only*
(*Compressor, evaporator, condenser, drier, connecting tubing)

Found that the heater on the refrige evap was bad.

RNick did an excellent job explaining how to remove heater from evaporator and reinstall.

If the heater is attached to the evaporator and Samsung considers it one part (i.e. your supposed to replace the evaporator and heater), would the Five Year Warranty on Sealed Refrigeration System mentioned earlier mean Samsung would cover the defective heater?

defrost samsung model RS2555SL with problems
freezer works great, fridge freezes up to a solid chunk of ice, and have to turn off and let it defrost for a few days, have to do this once a month.

I can put it into manual defrost and it does work and turn itself off when it hits about 60 degrees and thermistor has proper resistance readings at 18k ohms (frozen) it allows manual defrost, then around 6.3 k ohms (approx room temp)it shuts off the manual defrost power while the still beeping on the defrost cycle..

because the manual defrost works and shuts off it shows all driver chips,fuses and relays are ok, is the only other thing it can be the timer board chip firmware? Or is there another input that i have overlooked.

Is there a trick/backdoor to re-initialize this chip? TMP87CC40N by toshiba.

I notice the low power reset is a fairchild KA7533 and that samsung did not follow suggested guidelines of a pull up resistor on the output to the reset on the toshiba chip. this low power notification chip stops the main chip when power drops to critical levels from losing execution steps (we call that la-la land). Maybe the chip is going into consistent la-la land (not likely to be consistent) with voltage fluctuations (this fridge is in Mexico) I do not own any type of data logger to watch this voltage over a fewdays or a few hours. Any feedback on this would be appreciated.

fan kicks on when so not that either.

this product worked fine for 3 years.

as a backdoor patch/band-aid, I am thinking of putting in a resistor in series with the defrost sensor to shift the time on the defrost cycle to be longer since it could be that it just does not stay on long enough could be a cheat. I will probably try 2k ohms to start. By the samsung appendix I chart, this would shift from 66 degrees to 85 degrees when it shuts off assuming the auto defrost uses the same threshold as the manual threshold maybe clearing the remaining ice to solve the issue.

my 2.2 Kohm resister "fix" (some may say hack job) appears to be working, I am 6 weeks later and it has not frooooozen up in that time. So when I hit 2-3 months I will post pictures of what I did, I also made a drain heat pipe out of aluminum flashing to conduct heat from the heat coils to the drain area.

so my symptoms were it kept freeing up to a solid chunk so the temp in the fridge was 40-60 degree. this took 3-4 weeks before I had to remove everything and do this manual defrost. everything worked in sensors and such but it kept freezing up.

as a back-up though I have not installed it i purchased on the internet bidding site a cable drain heater gemline GH204 75 watts 115 volts.

9/5/2011 I am not 5 months and no problems. so i can conclude this solves my specific proble.

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