Panasonic Inverter Refrigerator model NR-BY602XS - suddenly not cold overnight

[beetle1303]

Re: Panasonic Inverter Refrigerator model NR-BY602XS - suddenly not cold overnight

Refrigerators don't make cold, they remove heat, so the evaporator might not feel very cold. the gurgling sound does suggest the compressor is running. But the diagnostic still gives an error?

I am actually quite uncertain about the Self Diagnostics instructions - seems to be a translation from Japanese to English, and some texts are quite unclear..

Here's the summary of the Self Diagnostics done:
1) Page7 - In process Inspection
- after 1 minute: Illuminance Sensor LED is On, indicating BAD
- after 30 minutes: All Freezer Control LEDs blinking - indicating BAD
** no description of what is BAD...

2) Page 11 - SELF DIAGNOSING FUNCTION
- based on the initial blinks (before they go off): PCD is BAD

3) Page 15 - Not cool at all [ Both PC & FC (compressor does not operate) ]
- based on the initial blinks (before they go off):
• Defect of control PCB.
• Communication error between IC1 & IC201

4) Page 16 - Cool, not enough [ Both PC & FC (compressor operates) ]
- based on the initial blinks (before they go off):
• Defect of communication circuit and EEPROM circuit of control PCB.
• Plug out and after 7 minute plug in again.

Same outcomes in repeated tests. If these tests are done correctly, and the outcomes interpreted correctly - all seems to point to PCB Board faulty. Or possibly some setting is locked permanently like "compressor lock", or "defrost on", etc...

[sam_sam_sam]

Re: Panasonic Inverter Refrigerator model NR-BY602XS - suddenly not cold overnight

By data plate do you mean this in the pic below?

I am just curious - if the compressor runs at whatever speed, and the inlet is slight cool, the outlet is warm (not hot), and the evaporator coil has refrigerant flowing with gurgling sound, etc, shouldn't the evaporator coil be slightly cool the the touch?

Look at the end of the ( evaporator coil ) and see where very small tube is on one of coil and see if ice is forming there if so and only in one spot and does not grow then you have restriction or a gas leak

Also remove the temperature sensor and warm it with your hand and see if the compressor will run at full speed

[beetle1303]

Re: Panasonic Inverter Refrigerator model NR-BY602XS - suddenly not cold overnight

Look at the end of the ( evaporator coil ) and see where very small tube is on one of coil and see if ice is forming there if so and only in one spot and does not grow then you have restriction or a gas leak

Also remove the temperature sensor and warm it with your hand and see if the compressor will run at full speed

There is absolutely no frosting anywhere around the evaporator coil.. I don't think the refrigerant inside the coil is cool enough to form frost/ice. Touching the coil can feel the gurgling liquid flowing, but no sense of coldness at all.

After power up for a few minutes, I place both defrost and freezer sensors in a cup of semi-hot water (around 50degC I guessed), but cannot really tell if the compressor is running at full speed or not.

After 10-15 minutes, no observable difference in term of coldness in both compartments.

How long does a normal fully working fridge takes to start feeling coldness if you place your hands in the freezer compartment?

[sam_sam_sam]

Re: Panasonic Inverter Refrigerator model NR-BY602XS - suddenly not cold overnight

That what I thought ( “gurgling liquid flowing” ) I being to think that either the compressor ( will not run at full speed )[Controller issues] or [ compressor pumping issues ]
OR
You have a restriction in filter dryer ( OR ) cap-tube
OR
You have a gas leak

This is where you would need a set service gauges and a specific type of amp probe to figure out what going on with this system

[sam_sam_sam]

Re: Panasonic Inverter Refrigerator model NR-BY602XS - suddenly not cold overnight

After 10-15 minutes, no observable difference in term of coldness in both compartments.

How long does a normal fully working fridge takes to start feeling coldness if you place your hands in the freezer compartment?

It should only take few minutes for the coil to start getting cold where the cap-tube is and the coil meet together

When hear the liquid flowing like this is not a good sign and not getting cold

There is not much refrigerant in theses units so if have a leak or a restriction it does not take it long for it not work

[beetle1303]

Re: Panasonic Inverter Refrigerator model NR-BY602XS - suddenly not cold overnight

OK. Let me summarize the options to move forward:
1) Refill refrigerant - this will determine if there is leakage. Maybe worthwhile
2) Replace controller board - If a used fridge of same model can be found at low price.
3) Replace some of the tubing - this will determine if there is blockage or restriction. Probably too costly for a old fridge..
3) Replace compressor - not worth the money..

Any feedback on these options? Or any other viable options?

[sam_sam_sam]

Re: Panasonic Inverter Refrigerator model NR-BY602XS - suddenly not cold overnight

OK. Let me summarize the options to move forward:
1) Refill refrigerant - this will determine if there is leakage. Maybe worthwhile (probably not)
2) Replace controller board - If a used fridge of same model can be found at low price. ( good idea if you can find one )
3) Replace some of the tubing - this will determine if there is blockage or restriction. Probably too costly for a old fridge..
3) Replace compressor - not worth the money..

Any feedback on these options? Or any other viable options?

I commented on your though but for the most part you are right

[beetle1303]

Re: Panasonic Inverter Refrigerator model NR-BY602XS - suddenly not cold overnight

OK... Looks like it's praying for a kind donor, or paying for a reasonable price used unit as tuition fee.

I have started browsing and found a few identical model, but price a little stiff after costing in transportation.

I guess will need a little more time to catch one...

[gurangax]

I have same model and about the same problem. Did you solved yours? My compressor doesn't spin. replaced with bulbs no lights. replaced IPM same problem. seems like this problem Communication error between IC1 & IC201 based on blink code

[ajshoe]

I have same model and about the same problem. Did you solved yours? My compressor doesn't spin. replaced with bulbs no lights. replaced IPM same problem. seems like this problem Communication error between IC1 & IC201 based on blink code

first of all - this refrigerator has a control bd that drives an inverter board that controls the compressor. The voltage coming from the inverter bd driving the compressor is 80 - 230 VAC. 1. test the compressor windings - should ohm out all the same. If all the same ohms between the 3 pins - compressor is probably good. 2. test the control bd by testing for 4V-6V volts going to the input of the inverter board - this is the voltage that drives the inverter board to put DC voltage to the compressor. Also test for 120 VAC going into the inverter bd. If no 4 VDC - 6 VDC voltage going to the inverter bd than control board is bad or a temp sensor is bad going to the control bd. 3. Look at the inverter board for burn marks.4. next I would test the amp draw of the inverter bd (should fluctuate between 1 - 3 amps) by using an amp meter on the 120 VAC input to the inverter bd - if its zer0 than the inverter bd is bad. If the amperage jumps to 4 amps and then declines to zero (this will cycle as the control bd realizes the compressor is not starting) - compressor is probably bad. 5. If you got this far and everything is good - the next test is to test the invert bd output with a phase detector (expensive piece of equipment) 6. finally either the compressor is weak or the system has a leak and is low on fluid. This is a closed system and no fluids should ever leak out. The inverter board is usually the culprit but not always. hope this helps !

[gurangax]

first of all - this refrigerator has a control bd that drives an inverter board that controls the compressor. The voltage coming from the inverter bd driving the compressor is 80 - 230 VAC. 1. test the compressor windings - should ohm out all the same. If all the same ohms between the 3 pins - compressor is probably good. 2. test the control bd by testing for 4V-6V volts going to the input of the inverter board - this is the voltage that drives the inverter board to put DC voltage to the compressor. Also test for 120 VAC going into the inverter bd. If no 4 VDC - 6 VDC voltage going to the inverter bd than control board is bad or a temp sensor is bad going to the control bd. 3. Look at the inverter board for burn marks.4. next I would test the amp draw of the inverter bd (should fluctuate between 1 - 3 amps) by using an amp meter on the 120 VAC input to the inverter bd - if its zer0 than the inverter bd is bad. If the amperage jumps to 4 amps and then declines to zero (this will cycle as the control bd realizes the compressor is not starting) - compressor is probably bad. 5. If you got this far and everything is good - the next test is to test the invert bd output with a phase detector (expensive piece of equipment) 6. finally either the compressor is weak or the system has a leak and is low on fluid. This is a closed system and no fluids should ever leak out. The inverter board is usually the culprit but not always. hope this helps !

Thank you I am trying to repaird the board as the compressor seems fine. I have replaced the IPM. and blink code seems to refer to communication error between the 2 CPUs. I checked the crystal oscilattor with osciloscope and confirmed to be working at specified frequency. The IPM used is PS21961-4. Maybe you can give me some more ideas. thanks

[ajshoe]

check the caps.

[gurangax]

check the caps.

alright I'll check them. thanks