Need to replace fridge freezer thermostat

[Yan]

Hello guys, my freezer dont defrost. I need to use an hairdryer to melt the ice/snow when thing start to come soft. I've done the autodiagnostic and its read " O" for the defrost thermostat. I've looked for the part to change, but the only part available OEM ( part # WPW10292244 ) is a complete harness with the t-stat and other connector for a hefty  price. So it's why I'm here to ask for a replacement t-stat. It dont bother me if I need to cut wires and do some soldering. I just want to avoid to replace a complete harness and pay too much for it. Here the informations:

Refrigerator :Inglis ITB19440Q02

T-Stat ident ( whats written on the T-Stat)

FPS 39TVER31    40056

L42--30F    S15912E

126393-24

 I have a pic of the thermostat, but I dont know how to attach it to the message here. If you can help me with a compatible replacement t-stat that will work with my fridge it would be greatly appreciated.

[16345Ed]

I’d replace with original part harness and all

 

The key marking on your thermostat is L42--30F. Opens at 42 degrees and closes at 30 degrees. 

If your splice one in I use a Butt connector filled with good silicone to protect connections from moisture  

 

[Budget Appliance Repair]

@16345Ed Actually you're half correct - Opens at 42 degrees but closes at 12 degrees, (the number after dash is temp offset, open_temp-offset=close_temp).

I use the Frigidaire 297216600 Defrost T-Stat which is rated N42-21 as a replacement for many that are in this general spec range, (has a male and a female straight plug connectors that will work on the Frigidaire's that you use it on and you cut the wires and wirenut into harness for most others).

Edited July 18, 2018 by Budget Appliance Repair

[16345Ed]

Just now, Budget Appliance Repair said:

@16345Ed Actually you're half correct - Opens at 42 degrees but closes at 12 degrees, (the number after dash is temp offset).

I use the Frigidaire 297216600 Defrost T-Stat which is rated N42-21 as a replacement for many that are in this general spec range, (has a male and a female straight plug connectors that will work on the Frigidaire's that you use it on and you cut the wires and wirenut into harness for most others).

Yes, sorry forgot to do differential 

[Yan]

On 7/18/2018 at 8:06 AM, Budget Appliance Repair said:

@16345Ed Actually you're half correct - Opens at 42 degrees but closes at 12 degrees, (the number after dash is temp offset, open_temp-offset=close_temp).

I use the Frigidaire 297216600 Defrost T-Stat which is rated N42-21 as a replacement for many that are in this general spec range, (has a male and a female straight plug connectors that will work on the Frigidaire's that you use it on and you cut the wires and wirenut into harness for most others).

Thanks all for the info. I was wondering what was the meaning of all those numbers. I found that W10165425 or WPW10165425 is often cited as a replacment. Do you know if the spec fit?

[Budget Appliance Repair]

None of the pictures I can find of that part so a good picture of the specs that are stamped into the black plastic and none of the parts listing show the specs so don't know if that one is the correct range or not.

I would have to see the actual part so I could read the specs off it to say for sure if it would work or not, (without doing a bunch of research and cross referencing).

[LearningTech]

W10165425 is an L60-32F and is too far off to be suitable

[LearningTech]

Ml45 is open 45 close 25 . Its close , but i would tryand find one closer. Or just get the original

[Yan]

Its very curious that everywhere I look for purchasing my original OEM thermostat they gave me W10165425 as a replacement for the 12639324.... and the spec are so far off L42-30F VS L60-32F. Which of this value is the most critical? The open temp ou the offset?  If I found a T-stat aroud 45-40 for the open value and something that goes around 20-30 of offset, do you think it will do the job without causing any damage at the evap?

thanks again

[Yan]

I think appliance manufacturers ( several models are absolutly the same exept for the desing and look ) are playing with us. I just found that another t-stat, the Whirlpool WP67003426 have absolutly the same spec as mine: L42-30F. Exactly the same physical look...but almost 10$ higher in price....changing parts number, for the exactly same part and differents prices.  As you someone said here before, I m not able to find a picture of the w10165425 clear enough to see the spec on it..

[Budget Appliance Repair]

On 7/18/2018 at 5:06 AM, Budget Appliance Repair said:

 

I use the Frigidaire 297216600 Defrost T-Stat which is rated N42-21 as a replacement for many that are in this general spec range, (has a male and a female straight plug connectors that will work on the Frigidaire's that you use it on and you cut the wires and wirenut into harness for most others).

This is what I would use to replace yours - it's one of the few defrost t-stat I stock and use it for most applications.

[Yan]

Thanks a lot for all your replies and hints.

[Rhubarb Tau]

Hi All, I know this is an old thread, but in case anyone stumbles across it I'll mention this. 

Ran a call today on a KESS907SBL00 for a defrost failure, found Bi-metal open despite < 0*F at evap. Tech sheet shows cut-out/cut-in as 42/12*F.  Breakdown shows Bi-metal available in Harness WPW10290745. 

MyPartsHelp.com (actually a pretty useful subscription site despite the silly name, not sure how many other techs use it) has a note for the Harness saying, "Note: PER FACTORY, THE DEFROST THERMOSTAT IS PRT # W10165425 RO 9/14" 

On 7/20/2018 at 6:59 AM, LearningTech said:

W10165425 is an L60-32F and is too far off to be suitable

That would explain why when I've followed this note for ala-carte Bi-Metals in the past, I've run into callbacks for continued defrost failures. I just gotta see the stamped spec for myself, going to pick up a W10165425 tomorrow to inspect.

[dwschnelli]

Some defrost terminators have an internal resistor, usually about 55k, that is used by ADC (adaptive defrost control, i.e. electronic circuit board) to determine how often and how long (duration) the defrost cycle has functioned, basically building a short defrost "history" to minimize energy usage. That helps explain why some terminators are specific, not necessarily just Open or Closed, but Open= 55k ohms.  My notes for W10165425 say "Opens @ 42 degrees, Closes @ 12 degrees; with 56k PTC (ohms incr with temp increase); has fixed 5/16" tube clip, 6" leads, no terminals; included in harness W10290745; not illus for heater 12729128"

[Budget Appliance Repair]

@dwschnelli The defrost t-stats that have a resistor in them, it is NOT a PTC resistor.  It is a fixed 55K ohm resistor internal to the bi-metal.   When open/any temp above the cutoff temp it will read 55K Ohms - when closed it should read 0 or very close to 0 Ohms.

[dwschnelli]

Thank you for that clarification Budget.  I'm not sure where that PTC notation came from, but I didn't make it up, I must have misread something on a tech sheet. This is the only terminator record that mentions it, so I will edit my database.

[Rhubarb Tau]

Following up, I picked up a WPW10165425 this morning. It's stamped "L42-30F", which would match the 42 / 12 *F cutout/cutin spec. I was curious how accurate these are, so I tested it. Turns out pretty accurate. I measured 42 / 10*F, and the accuracy of my setup seems to be ~ +/- 3*F.

 

Edited October 13, 2019 by Rhubarb Tau
Rearranged images

[LearningTech]

On 10/12/2019 at 6:08 PM, Rhubarb Tau said:

measured

What do you use to measure resistance and temp at the same time? That would be a usefull tool 

[Rhubarb Tau]

Surprisingly I haven't found anything reasonably priced off-the-shelf that will log 2 channels of different signals, so I rolled my own. I used an Arduino-type development board with an AD8495 thermocouple amplifier, logged the 2 channels of data to a .csv on a SD card, then graphed the csv in Google Sheets.

If there's an easier answer, I'd be interested. Pretty often when taking a measurement, I'm looking for the response, what's value A when value B is THIS.

I've used Dataq data recorders before, but the affordable ones are all 0-5V input (at least last time I checked, years ago).