My refrigerator Model #59672383411 Kenmore bottom-mount refrigerator. Refrigerator section will not go below 40 Degrees

[Russ B]

Hi, I thought you had left forever, Welcome Back... Thank you for responding.. I have changed out the ref sensor earlier with a new one no difference. But willing to try measuring the resistance.. Do you know the plug and terminals that are the ref. sensor? I do not have a wiring diagram or I would know which plug and terminal it is.. I had also thought that the voltage to the ref temp sensor might be getting the wrong supply voltage, is that supplied by the control board or  the power supply board?

I have hooked up a O-Scope to the square wave output of the control board Plug 8 terminals 8 and 9, (info that you gave me). So I can now see the output of the control board it seems like it has only two or three speeds or the variation is so small I cannot track it with the scope...

It is still funny that I can measure 8 degrees on the inlet to the ref evaporator coil but I only get 38 degrees at the tower air outlet.. I know the tower does not have any obstruction. The fan and sensors are new..  I have a hand held IR thermometer, maybe I can look at the ref evaporator coil and see how the temp varies through out the coil.. Could there be an obstruction in the freon line of the ref evaporator. 

 

Again thank you for the response,

[Russ B]

PS I had a discussion with another appliance tech that suggested the the Inverter unit was bad, but I could not see how the inverter would be bad if the compressor is responding to the square wave out of the control board..

[Rhubarb Tau]

On 11/21/2018 at 9:04 PM, Rhubarb Tau said:

I'd test the Ref. cabinet sensor (you might find a tech sheet under the right ref hinge cap or behind the toe-kick),

 

[Rhubarb Tau]

I don't know the algorithm that determines compressor speed based on cooling required, only the inverter speed signal that we discussed before.

If the inverter is running the compressor whenever it's being told to (with the square wave), then it's not faulty.

I would try to get a sense of the compressor runtime. If it's running almost constantly (even at low speed) but not reaching below ~ 40*F in the Ref. cabinet, you may have a sealed system problem, despite what to my eye looks like a reasonable frost pattern. at 70*F ambient, the runtime spec for the compressor is 50% +/- 10%.

I would also look at the freezer temps and frost pattern. This unit shares refrigerant between the Ref. and Frz. evaps. If there's a leak, it's likely to show up in the Frz. evap first (not sure why, just guidance from the Mfg.)

[Russ B]

Hi, Found the wiring diagram, I will look it over and let you know what I find tomorrow or may be the next day I have to get a blood test tomorrow..

[Russ B]

I know the freezer has been holding constant 0 degrees.. But still does not mean that there could be a obstruction in the ref evap line.. Will do as you suggest hopefully tomorrow. Is the ref evap line obstruction very unusual? The funny part is the ref and freezer are holding steady and has been for a couple weeks now, freezer at 0 and the ref at 39-40 degrees..

[Rhubarb Tau]

18 minutes ago, Russ B said:

Is the ref evap line obstruction very unusual?

Yes, a restriction is very unusual, especially if the sealed system has never been worked on.

[Russ B]

That makes me feel a little better, we purchased the ref new so it has never been worked on.. II almost sounds like there is a resistive contact somewhere causing the sensor to be misread and now with the wiring diagram I can do as you suggested and do some measurements. 

Will keep you informed..

Thanks again,

[Russ B]

Just thinking over night do you think the control on the door that sets the temperature of the ref and freezer could be an issue?

[Russ B]

Just ran the Refrigerators Self-diagnostics for FC thermistor (OK), RC Thermistor (OK), Compressor speed test (OK, I watched it go up and down in speeed), Pantry thermistor (OK), Compressor/condenser/condenser fan motor/Evaporator fan  (OK)..  I have not yet ran a resistance test on the thermistors yet, the sheet says for 77 degrees should be 2700 +/-5%, 36 Degrees 8000 +/-1% and 23345 +/- 2%..

[Russ B]

I just started to do the resistance check on the units RC and FC thermistors .. Something is not right according to the Wiring diagram the RC sensor goes to pins 1-2 on P5 control board wiring harness.. I ran an ohm meter and got nothing so I tried the FC thermistor connecting pins 3-4 on P5 control board wiring harness also got nothing.. something is not right going to have to do a wiring continuity check but I will have to take out the food again to get at the sensor.. will probably be tomorrow..

[Russ B]

I finally got to the FC and RC thermistors through the refrigerators wiring measured at the P5 wiring harness, they measure RC Sensor 7.9 k ohms (at 39 Degrees) and the FC Sensor 26K ohms (at -2 degrees) respectively.. Both are near specs.   I made a rookie mistake when measuring the resistances originally and didn't switch ranges on the ohm meter, boy did I feel dumb... 

I have also switched out the power supply board W10453401 without any changes..

Back to being lost but I will try to get the run times of the compressor as you suggested earlier..

[Rhubarb Tau]

Maybe I'm just playing devil's advocate here, but I'll bet if you totalled up the cost of the parts that you've already installed that haven't resolved the problem, you're well past the cost of having a professional diagnosis. I think it might be time for that. I'd recommend calling your nearest Whirlpool-approved servicer (not Sears, this is a WP-built unit). It looks like in your area that might be Brandts Appliance Parts & Services in Vero Beach.

[Russ B]

The parts replaced so far are about $120 since I have used parts from cosmetically damaged units.. And considering I have not yet resolved the problem with replacement parts leads me to think it is probably in the closed system I have noticed the compressor is running almost constantly which probably means a leak somewhere.. Before I go any buy a new unit I am wondering if it would be worth calling in the tech you described "Whirlpool-approved servicer", since the compressor has been running as long as it has will it also be open to failure? Sound like the opening of the system and possible replacement of more parts and labor would be worth it..

What would you do if the unit was yours?

Again thank you for your help,

 

[Russ B]

If I do decide use a Whirlpool-approved servicer  do you have a list of them in the 32951 area?

[Rhubarb Tau]

2 hours ago, Russ B said:

If I do decide use a Whirlpool-approved servicer  do you have a list of them in the 32951 area?

Reread my last post carefully. Specifically the last sentence.

[Russ B]

I did read your last post and appreciate it.. Vero Beach is about 25 miles away is there anything near Melbourne, Fl? What would you do if the unit was yours new or call in the services?

[Russ B]

I have set up an appointment with Brandts Appliance Parts & Services in Vero Beach as you suggested.. I will let you know the outcome..

[Russ B]

Hi, this is what the tech said about the refrigerator..

Brandt's Appliance Service 772-562-5759, WWVV.BRANDTSAPPLIANCESERVICE.COM Thank you for your business. 
Burden. Russell 
12/18/18, # 253605 Refrigerator, Amana 569.72383411, K51803779 Found the units rc temp at 41.4*F as reported by the cust. Cust has a working background in electronics and is highly knowledgeable on the this unit and its working. Cust has installed multiple component parts to include the hv control, power board, rc evap fan motor, etc. and has conducted voltage / resistance tests confirming proper range of all thermistors, motors, inverter control, etc. Through test results temp issues is believed to be due to a faulty switching valve and/or a faulty fc evap fan motor allowing for interfearance with the switching valve. Cust will be conducting additional tests and if needed will conduct repair to correct. Cust to advise. Cust has paid service charge.

[Russ B]

Changed out the FC evaporator sensor and motor no change.. Thew next thing I am going to try is to measure the closed system freon pressures..

 

[Russ B]

The closed system FC Side is at about 4 psi on the suction side and the suction side return pipe from the evaporator is slightly icing.. When the RC side is running the suction pressure is about 9 PSI and the suction return pipe is not cold.. The 3 way valve sounds like it is switching.  

I would think that would mean that the RC evaporator has some obstruction or the 3 way valve is now opening to the RC evap.. 

Any further ideas?

[Russ B]

By the way the compressor off pressure is about 34 PSI..

[Russ B]

Guess I jumped the gun on my readings apparently forgot the inverter runs the compressor at different speeds.. So after seeing the frost on the FC evaporator pipe return and the 3 way valve switched. the RC evaporator pipe return was cool. Both RC and FC pressures were about 4 Psi when running..