Hitachi Refrigerator R-Z270AUN7KV not cold.

Collapse
X
 
  • Time
  • Show
Clear All
new posts

  • R_J
    replied
    Re: Hitachi Refrigerator R-Z270AUN7KV not cold.

    I don't know what the timer motor resistance will be, but it is likely fairly high, If it reads anything but open it is likely ok. You can replace it with a different duty cycle, it's not that critical, It doesn't know how much frost is built up at any time so anything will work better than nothing, If you put a lot of hot steamy food in the fridge it will frost up faster.

    Leave a comment:


  • SuperAman
    replied
    Re: Hitachi Refrigerator R-Z270AUN7KV not cold.

    Originally posted by R_J
    I don't know which one it is but if you look at the schematic, there are two, a thermal fuse and a defrost thermo (thermostat) , You said that when you turned the defrost timer so it would defrost that it was working and heating up. if this is the case both thermo devices must be working.

    Did you check the defrost timer motor resistance? If the defrost element was heating up when you turned the timer to its defrost position, you have likely found the problem, if the other parts were bad it would not heat up.
    I will check it, I put it back together, so I'll have to take it apart again. What kind of resistance values should I be getting from the timer motor?

    Leave a comment:


  • SuperAman
    replied
    Re: Hitachi Refrigerator R-Z270AUN7KV not cold.

    Originally posted by R_J
    I believe the defrost timer in my fridge works like this, for every 6 hours of "compressor run time" the timer will then defrost for 25min.
    The TMDFX05CD1 = for every 12H of run time it defrosts for 6min
    So can I replace mine with one that runs 6, 8, or 10 hrs? I don't think I can find one locally that runs 12hrs. Importing one would be cost prohibitive (customs duties and all).

    Leave a comment:


  • R_J
    replied
    Re: Hitachi Refrigerator R-Z270AUN7KV not cold.

    I believe the defrost timer in my fridge works like this, for every 6 hours of "compressor run time" the timer will then defrost for 25min.
    The TMDFX05CD1 = for every 12H of run time it defrosts for 6min
    Last edited by R_J; 03-02-2021, 06:54 PM.

    Leave a comment:


  • redwire
    replied
    Re: Hitachi Refrigerator R-Z270AUN7KV not cold.

    If the fridge runs say 6 minutes every hour (10% duty cycle) with a 6min/12hr defrost timer (wired to the compressor) it will defrost every 5 days for 1 hour. Seem too long to me, but not relevant to OP's problem. It might be a schematic error.
    I've had problems with a leaking door seal on the freezer causing the evaporator coils to ice up.
    Reposting the schematic for the Hitachi fridge.

    The fixed thermostat in the evaporator coil goes open-circuit when it's hot, but will read zero ohms cold - Some popular defrost thermostats: Open 45°F, Close 25°F, Differential 20°F; another is Open 55°F, Close 35°F, Differential 20°F. Not zero ohms at room temperature.

    So the thermostat needs close to freezing or colder for the switch contacts to close.
    Attached Files

    Leave a comment:


  • R_J
    replied
    Re: Hitachi Refrigerator R-Z270AUN7KV not cold.

    I don't know which one it is but if you look at the schematic, there are two, a thermal fuse and a defrost thermo (thermostat) , You said that when you turned the defrost timer so it would defrost that it was working and heating up. if this is the case both thermo devices must be working.

    Did you check the defrost timer motor resistance? If the defrost element was heating up when you turned the timer to its defrost position, you have likely found the problem, if the other parts were bad it would not heat up.
    Last edited by R_J; 03-02-2021, 11:17 AM.

    Leave a comment:


  • SuperAman
    replied
    Re: Hitachi Refrigerator R-Z270AUN7KV not cold.

    Originally posted by R_J
    The defrost timer only runs when the fridge/compressor is running. The defrost motor is connected across pins 1 & 3, check the resistance of the motor, if it is good then maybe you can get some type of cleaner to wash out the motor and the reduction gears inside it? If not just replace the timer, If you can find a used one it should be ok, you can order them off the internet, just be sure to get the right voltage (ac200~240)
    #54 on the diagram is that a temp sensor for the heating element? I'm getting open reading with the meter. How do I test that? I think it might be faulty as well. There are two thermostats in the freezer compartment one is embedded in the coils and the other one next to the fan motor. How do I check them with a meter?
    Last edited by SuperAman; 03-02-2021, 01:56 AM.

    Leave a comment:


  • R_J
    replied
    Re: Hitachi Refrigerator R-Z270AUN7KV not cold.

    The schematic of this fridge is in post#11, You can see that the thermostat switches the a/c on and off to everything but the fridge lamp. The defrost timer only runs when the thermostat is closed, When it is time to run the defrost cycle the compressor is turned off. The defrost cycle time is not that critical as the amount of frost built up is also not predictable.
    Last edited by R_J; 03-01-2021, 11:06 AM.

    Leave a comment:


  • redwire
    replied
    Re: Hitachi Refrigerator R-Z270AUN7KV not cold.

    These timer motors run constantly I thought?
    The switch seems to be in series with the compressor, so they disable it, run a heater cycle to defrost, and then allow power for the compressor again.

    You could check the timer motor's resistance (pin 1-3) to see if it is open-circuit or not. The leads are not soldered to the tabs so maybe a bad connection. Some diagrams show a resistor or fuse "C"? in series with the timer motor.

    Sankyo/Hitachi TMDFX05CD1 is a special cycle time, 6min/12hr.
    TMDF706CD1 is close, 7 minutes defrost with 8hr cycle (50Hz).
    Attached Files

    Leave a comment:


  • ron350
    replied
    Re: Hitachi Refrigerator R-Z270AUN7KV not cold.

    RJ cant he just hook up AC200-240 to pins 1and 3 and see if the motor works?

    Leave a comment:


  • R_J
    replied
    Re: Hitachi Refrigerator R-Z270AUN7KV not cold.

    The defrost timer only runs when the fridge/compressor is running. The defrost motor is connected across pins 1 & 3, check the resistance of the motor, if it is good then maybe you can get some type of cleaner to wash out the motor and the reduction gears inside it? If not just replace the timer, If you can find a used one it should be ok, you can order them off the internet, just be sure to get the right voltage (ac200~240)
    Last edited by R_J; 02-28-2021, 02:10 PM.

    Leave a comment:


  • SuperAman
    replied
    Re: Hitachi Refrigerator R-Z270AUN7KV not cold.

    Originally posted by R_J
    Maybe it can be fixed? I don't have it to be able to tell. There is no adjustment, it is a timer, I suspect the small internal motor is not turning for some reason.
    There should be a way to access the timer (post #6) so you can operate the switch manually by turning it with a flat screwdriver. maybe the access hole is under panel 42 or 36? If you can access it you can turn it to the defrost cycle, let it operate that way for about 10min, then advance it again to let the compressor operate.
    Thanks I found the little guy. The schematics were right, mine is a little larger though. I don't think I'm going to find a new one locally though. How many hours is this model, it is not clear? Can I replace with another one that is the same shape and maybe less hours of cooling and lower minutes of defrost? The heating element works because when I manually rotate counter clockwise the heating element starts and runs and some of the build up of ice is melted. Since there is so much buildup 1 manual defrost cycle wont cut it. The good thing is the timer is accessible, it os just above the fridge temp knob and there is a hole to rotate a screw driver.


    Leave a comment:


  • R_J
    replied
    Re: Hitachi Refrigerator R-Z270AUN7KV not cold.

    Maybe it can be fixed? I don't have it to be able to tell. There is no adjustment, it is a timer, I suspect the small internal motor is not turning for some reason.
    There should be a way to access the timer (post #6) so you can operate the switch manually by turning it with a flat screwdriver. maybe the access hole is under panel 42 or 36? If you can access it you can turn it to the defrost cycle, let it operate that way for about 10min, then advance it again to let the compressor operate.
    Last edited by R_J; 02-03-2021, 02:58 PM.

    Leave a comment:


  • SuperAman
    replied
    Re: Hitachi Refrigerator R-Z270AUN7KV not cold.

    Originally posted by R_J
    NO that is the fan motor, The defront timer is #38
    Yes 38 I meant. So is there a way to fix it or adjust it? Or does it have to be replaced? It's a pain to access, much easier to access the freezer compartment.

    Leave a comment:


  • R_J
    replied
    Re: Hitachi Refrigerator R-Z270AUN7KV not cold.

    Originally posted by SuperAman
    Thanks mate, it is a very similar model. Is it the #31 part in the diagram the defrost timer, I had suspected that was it? It did it again this week it worked fine for like a month or so.
    NO that is the fan motor, The defront timer is #38

    Leave a comment:


  • SuperAman
    replied
    Re: Hitachi Refrigerator R-Z270AUN7KV not cold.

    Originally posted by R_J
    I suspect this is a similar fridge, It looks like it is item #38 behind the panel in the fridge compartment
    Thanks mate, it is a very similar model. Is it the #31 part in the diagram the defrost timer, I had suspected that was it? It did it again this week it worked fine for like a month or so.

    Leave a comment:


  • R_J
    replied
    Re: Hitachi Refrigerator R-Z270AUN7KV not cold.

    I suspect this is a similar fridge, It looks like it is item #38 behind the panel in the fridge compartment
    Attached Files
    Last edited by R_J; 11-18-2020, 04:47 PM.

    Leave a comment:


  • sam_sam_sam
    replied
    Re: Hitachi Refrigerator R-Z270AUN7KV not cold.

    It might be with the temperature controller sensor behind the cover would be my guess

    This timer might not have outside access to outside world would be my guess

    But who knows where it could be
    Last edited by sam_sam_sam; 11-18-2020, 06:47 AM.

    Leave a comment:


  • R_J
    replied
    Re: Hitachi Refrigerator R-Z270AUN7KV not cold.

    I don't know where they put it on this model, but if it is a frost free refrigerator, it is there somewhere.
    Here is the manual, with the schematic, trace the wiring to find the defrost timer, maybe it IS inside behind a panel somewhere?
    The pictures are too small to make out what's behind that black box where the cord enters
    Attached Files
    Last edited by R_J; 11-15-2020, 12:27 PM.

    Leave a comment:


  • SuperAman
    replied
    Re: Hitachi Refrigerator R-Z270AUN7KV not cold.

    Last edited by SuperAman; 11-15-2020, 10:13 AM.

    Leave a comment:

Related Topics

Collapse

  • Th3_uN1Qu3
    Cooling upgrade on refrigerator. If it works, it ain't stupid!
    by Th3_uN1Qu3
    I had this refrigerator at my old folks which I noticed I would put my beer or soda in and take it out warmer than I'd brought it from the store.

    Now, I don't know much about refrigerators or HVAC but to me it seemed like we have a problem. I threw a thermometer in... 20 deg C in the fridge. WHAT THE... Freezer worked fine with temperatures way below zero, as it should, and it has only one compressor for both sides so it got me scratching my head for a while.

    Only other things that seemed a bit odd was that the heatsink on the back was barely warm and the...
    09-03-2023, 06:29 AM
  • connorcc2005
    Kenmore refrigerator adaptive defrost timer fix. Part: AP4909015
    by connorcc2005
    I have a 20 year old Kenmore side by side refrigerator that was acting up with the following issues:
    • Evaporator coil in the freezer was frozen up.
    • Unit was still holding temperature
    • Evaporator fan would run 2 to 3 seconds on then shut off only to repeat.
    Defrosted the evaporator coil and began testing. Defrost heater ohmed out good. Defrost thermal switch on the evaporator line in the freezer tested good. Once the evaporator coil was defrosted, the freezer and fridge worked but the fan continued to cycle on and off continuously. I suspect the evaporator coil was destined to freeze up again...
    03-20-2024, 01:14 PM
  • CG2
    Liebherr Fridge Freezer KGT 3456 not working
    by CG2
    To be a bit more specific, I've got a 20-ish year old Liebherr that has just stopped working. This was quite a sophisticated beast for its time. It's a twin compressor model, and you set the desired temperatures of the fridge and freezer parts from a couple of little control panels above the door. It displays the actual temps on some eight segment displays there, flashing if it's working to get to where you want it. There's a control board with a microprocessor on it that read the temperature from a couple of sensors, switches the compressors on as necessary, and runs the display. There's also...
    01-25-2023, 02:12 PM
  • mikey5791
    Help repair Panasonic fridge not cooling
    by mikey5791
    Hi all forum members,

    Few days ago, i might have forgotten to close my home fridge freezer door completely. The next day, the ice cubes and frozen meat almost melted halfway and the freezer doesn't feel cool. I shut it off, wipe dry and let it air dry for one whole day. The next day i switched on the fridge, the compressor run for a second and it shuts off(no vibration and no sound at all) only the internal freezer compartment fan is running but is not cooling even i switched on a full day.
    After shut off, i dismantle the rear water pan holder and reached to the compressor wiring....
    07-16-2025, 02:01 AM
  • beetle1303
    Panasonic Inverter Refrigerator model NR-BY602XS - suddenly not cold overnight
    by beetle1303
    I have a 7-year old Panasonic inverter refrigerator model NR-BY602XS that went from working normally to completely not cold air overnight (both freezer and refrigerator compartments...

    The service manual instruction on Self Diagnostic Test seems to indicated Compressor faulty or locked. But the compressor seems to be working with humming sound and vibrating at variable speed and noise level..

    Everything else seems to be working normally - power cycled a few times has no effect. All the interior lights, and fan are working. I dismantled the interior panel to expose...
    04-18-2020, 08:12 AM
  • Loading...
  • No more items.
Working...