Rank: Member
Groups: Registered
Joined: 12/3/2008(UTC)
Posts: 13
|
I already own a Fluke DMM (I do small side jobs, elec., plmbg., hvac, etc.).
|
|
|
|
|
|
Rank: Member
Groups: Registered
Joined: 12/3/2008(UTC)
Posts: 13
|
How would I check this? I pulled the back panel off of the evaporator and found heavy frost on the coils (thicker at the top, lighter at the bottom). I took an ohm reading between the blue wire on the blue connector and the orange neutral wire on the board (conn. J7) and read it as 21-22 ohms. I then measured voltage from orange wire @ J7 to defrost terminal J9 on main board and came up with 1.2v. How would I test/measure the defrost heater? It sounds like it's the heater and possibly also the thermistor. It appears as though the "repairdude" that my inlaws hired, replaced the thermistat, as the wires have been cut and are reconnected with wire nuts (shouldn't they be "sealed wire nuts").
|
|
|
|
|
|
Rank: Advanced Member
Groups: Senior Expert
Joined: 8/13/2008(UTC)
Posts: 3,097
|
The best way to test those is for continuity, if they have continuity they should be good. We like to use the tube/crimp type connectors as opposed to the wire nuts.
Nat
|
|
|
|
|
|
Rank: Member
Groups: Registered
Joined:: 5/4/2008(UTC)
Posts: 2
|
hey,its the defrost heater...after that check to see if the damper opens up sometimes u have to open them up with your finger..i have a 252 unit place with these frigs and my heaters go out left&right
|
|
|
|
|
|
Rank: Advanced Member
Groups: Senior Expert
Joined: 2/29/2008(UTC)
Posts: 19,638
Thanks: 1 times
Was thanked: 11 time(s) in 11 post(s)
|
Best way to check the defrost element is directly across it.
At least one side must be disconnected so you do not read an alternate/parallel circuit path. Cut the wire if you have to.
Wire nuts are not the best solution but most DIYers don't want to invest in a crimper. I just use a wire nut, make sure it is good and tight and the use a zip tie to hold it out of the way and also with the open end facing down. |
THIS FORUM IS DEAD!!!!!!! |
|
|
|
|
|
Rank: Advanced Member
Groups: Senior Expert
Joined: 5/28/2008(UTC)
Posts: 1,620
|
You can use a wire nut, just make sure you seal it with silicone to keep moisture out of the wires.
|
|
|
|
|
|
Rank: Member
Groups: Registered
Joined: 12/3/2008(UTC)
Posts: 13
|
As a matter of fact, I have several crimpers (different types and brands) that I use for different types of connectors and different situations. I did observe the damper open, then close, so I know that it works. I will be ordering the heater and sensor immediately. The thermostat appears to have been replaced, as I noticed that the wires were cut and wirenutted back together. I didn't test the thermostat, but will do so when I replace the other parts, just to be safe.
|
|
|
|
|
|
Rank: Member
Groups: Registered
Joined: 12/3/2008(UTC)
Posts: 13
|
OK, I replaced the heater and the evap. sensor today. I ohm'd the old heater and had continuity. I also ohmed the thermostat when I disconnected it to install sealed wire nuts, and had continuity there as well. I plugged in the frig. and after a short time, the bottom of the coils started showing frost. How long before the defrost heater comes on? How/when will I know that it's working? Could it be the motherboard? How can I check this? Also the sensor that I removed, had no continuity, nor did the new one.This frig. doesn't have a digital diplay, only a couple of dials. Is there a service manual for this frig.?
|
|
|
|
|
|
Rank: Advanced Member
Groups: Senior Expert
Joined: 2/29/2008(UTC)
Posts: 19,638
Thanks: 1 times
Was thanked: 11 time(s) in 11 post(s)
|
Sounds like the board is shot.
The heater and the thermostat measure OK
The thermistor measures bad but perhaps you were not on a high enough meter scale. Should be around 6 kilohms at room temperature
To check try the below to force it into defrost
Set the freezer and refrigerator temperature settings to 5.
Press and hold all 4 temp adjustment buttons for approximately 3 seconds.
Flashing 0 in both displays indicates that the unit is in Self Diagnostic mode.
Set the freezer control to 1 and the refrigerator to 4, for a defrost test.
When a test code has been entered, the displays will flash to confirm the test.
Press the HOLD button for 3 seconds to begin the test.
If the thermostat is cold enough (closed) the heater should come on.
You can also check the thermistors
Diag code is 0 7
P is a pass
Ignore the third read out unless the unit has Quick Chill
Evap thermistor is the 4th raeding
. |
THIS FORUM IS DEAD!!!!!!! |
|
|
|
|
|
Rank: Member
Groups: Registered
Joined: 12/3/2008(UTC)
Posts: 13
|
The unit doesn't have a digital display or digital settings, only a couple of dials. So how would I check the board to see if it's bad? Also, how do I activate the defrost to see if it's working, or if it's the board. Can the new heater be returned once it's installed, but determined that that isn't what's wrong, and credit be given towards a new board?
|
|
|
|
|
|
Forum Jump
You can post new topics in this forum.
You can reply to topics in this forum.
You can delete your posts in this forum.
You can edit your posts in this forum.
You cannot create polls in this forum.
You can vote in polls in this forum.
Important Information:
The AppliancePartsPros.com uses cookies. By continuing to browse this site, you are agreeing to our use of cookies.
More Details
Close
