Dumbstruck by the new computer-controlled appliances? Let the Samurai enlighten you…

Click here to check out our structured, online appliance repair training courses for rookies and experienced techs.

FAQs | Repair Videos | Academy | Newsletter | Podcast | Contact

Stay connected with us...

Samurai on Facebook - become a fan today! Sign up for our free newsletter and keep up with all things Appliantology. Subscribe to our YouTube channel for lots of appliance repair tips and help! Follow the Samurai on Twitter and get timely morsels of Appliantological Wisdom! Subscribe to our MST Radio podcast to learn secrets of the trade.
  • Announcements

    • Samurai Appliance Repair Man

      Webinar Recordings Index Page   07/27/2017

      One of the benefits of your Professional Appliantologist membership is that you can attend the regular, live training webinars and you have access to the recordings as well. So if you can't make it to the live webinar, catch the recording at your convenience. The webinar recordings are conveniently listed for you on the Webinar Recordings Index Page.   
cuzzin sam

a general defrost question

Recommended Posts

cuzzin sam   
cuzzin sam

I unfortunately don't have the model # for this GE side by side but I'm hoping someone can shed a little light anyway.

I first went to this call and found the evap frozen and the defrost heater burned out. I replaced the hearer, defrosted and left only to be called back a few days to find the evap frozen again. The heater and the termination thermostat both read closed so as an experiment I jumped around the thermostat, defrosted and left.

A couple of days later it was frozen again so thru a process of elimination I decided it had to be the board...which I changed...and of course it's frozen again. This parts changing idjiit is getting tired.

Does the board send the unit into defrost based on time or is there a thermister or something that tells the board when to initiate a defrost cycle? If I jump the terminals on the board (I read that here last night) am I simply supplying voltage to the defrost circuit or am I closing the defrost relay on the board? And the big question, has anyone ever seen someone change so many parts with no appearent idea of what he's dong? Thanks for the desperately needed help, Sam

Share this post


Link to post
Share on other sites

Need appliance parts? Call 877-803-7957 now!

RegUS_PatOff   
RegUS_PatOff

... or is there a thermistor or something that tells the board when to initiate a defrost cycle?

yes ,. when to terminate the Defrost
The Control Boards usually have a test for ther Thermistors and the Defrost Cycle
Freezer may have (2) of these
Fridge may have (3)
click on picture
Thermistor-WR55X10025-00855831.jpg

the "older" style were prone for failure
http://fixitnow.com/wp/2010/06/30/ge-profile-and-arctica-refrigerators-upgraded-thermistors/
  • Like 1

Share this post


Link to post
Share on other sites
Samurai Appliance Repair Man   
Samurai Appliance Repair Man

No, the board decides when to initiate defrost based on door openings, and other factors. The evaporator thermistor tells the board when to terminate the defrost; the board terminates defrost when the thermistor reads 75F. Now, suppose the thermistor's resistance was such that the board always thought it was 75F, what would happen? Answer: the board would never initiate defrost because it thought the evaporator was already too warm.

Check the thermistor resistance by placing it in a glass of ice maker. Should get about 16 K-ohms. If it's one of the old style, it needs to be replaced in any event.

Thermistor part link ==> http://www.repairclinic.com/PartDetail/Thermistor/WR55X10025/914093

Thermistor-WR55X10025-00855831.jpg

  • Like 1

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now