Saltar al contenido principal

Why is my freezer not freezing?

Hi everybody :)

I tried to find the why for more days now, and am now on my way to give up.

I have a RSH1DTMH american fridge-freezer, and have some problems on the freezer part, fridge working well after mooving the temperature sensor.

Freezer is not freezing, i can’t tell at what temerature it keeps, but certainly above 0°C because water put in stays a water.

I checked the temperature sensor with the ohm meter, and it seems OK, checked the defrost heater (manual forced defrost) - works well, and the fan inside the freezer - is OK.

I’m not sure where is the defrost thermostat, i see 2 pieces that looks similar to the thermostat I saw on some videos on youtube treating different fridges, but i’m not sure if it’s this and anyway seems more complicated to get out because the wires going out of it doesn’t go to one place.

What’s more when the fridge is turned on I can see that the freezer is trying to do something, because after few minutes you can see a lot of frost on one tube. The other thing is that temperature on the panel is getting lower to reach after a long time the temperature that I set so -19°C. It takes a long time, between half a day and one day, but finally it shows and stays at -19 but that’s not right, because the water put inside doesn’t even freeze.

Join some pictures to show what I’m trying to explain :)

Any help appreciated :) !!

Block Image

Block Image

Block Image

Update (10/09/2020)

It went into forced operation, but it didn’t make any sound.

I mesured again the sensor while the dispaly is showing -25°C, I join the picture because I’m not sure if I did it with correct setting of ohm-meter.

Block Image

here’s how it’s frosted at the moment

my estimation is that it’s around +20°C inside the freezer

Block Image

Update (10/09/2020)

And here is the image of the temerature sensor

It was attached to the tube going out of the silver reservoir with a plastic attach but i took it out to be able to disconnect it totally

Block Image

Contesta esta pregunta Yo también tengo este problema

Es esta una buena pregunta?

Puntuación 3
2 comentarios

Please, any ideas what to do now?

Frezeer is showing -25°C and there’s some more frost (like by the first picture) but the temperature is ambient

- de

Mines doing exactly the same - did you find a solution ?

- de

Agregar un comentario

2 Respuestas

Respuesta Más Útil

katkacyt here is the SM HM09 SM. Run the diagnostics as outlined in page 48. Let us know what you find out

Update (10/08/2020)


The parts marked a thermostats are what turns you heater off

Post an image of the temperature sensor that you measured

Block Image

That looks like the sensor but it should be on the coils/tubing. Give us a close up of that

Fue útil esta respuesta?

Puntuación 2

2 comentarios:

Thanks for your answer!

I put the fridge in FF mode, but it's doing nothing. After few seconds it goes back to a normal display. But the fridge was disconnected for the whole night, maybe I should do it after a while, when freezer shows - 19°C?

By the way, my fridge doesn't make any sound, is this a problem of a main board or something I could look for?

- de

Still the same today, diagnostics shows nothing

- de

Agregar un comentario

Hi,

You said that “I checked the temperature sensor with the ohm meter, and it seems OK, ….”. Just curious whether it was it showing the correct resistance for the temperature indicated or not?

Here’s a composite image taken from the service manual and the 502AT thermistor datasheet showing the resistance value for the thermistor at the various temperatures.

Block Image

(click on image to enlarge for better viewing)

Did it go into forced operation and signal that it did after you left it overnight? (see p.66 or 67 of the service manual)

Update (10/09/2020)

Hi,

Can’t see it to well from your image but did you measure the sensor out of circuit i.e. disconnected from where it plugs into the connector at the back and measured directly across the sensor wires themselves, not at the plug point still plugged in? Hopefully this makes sense ;-)

The reason is that as can be seen from the wiring diagram (see below) the sensor is in parallel with some other sensors and if measured with it still connected the reading on the meter wouldn’t be accurate.

If you didn’t measure it when disconnected, unplug the sensor and measure directly across the two sensor wires at their plug and not at the socket that it plugs into. That way you are looking only at the sensor with the meter. Try not to touch the sensor itself with your fingers as this will start to warm the sensor and alter the reading.

If you did measure it out of circuit and the reading was 7.5 Ohms then this indicates a temp of appprox. 15C

Block Image

(click on image to enlarge for better viewing)

The fact that the sensors are all connected would be taken into account when the circuit was designed so as to give an accurate display but would still rely on the fact that the sensor has to give the correct resistance reading at the specified temperatures whether it was connected as it is or as a standalone sensor.

Update (10/15/2020)

Hi @katkacyt,

One thing that may have been overlooked as I couldn’t see it mentioned in the question/comments etc.

Is the evaporator fan in the freezer operating? The door may have to be closed for it to operate as usually evap fans are turned off when a door is opened to prevent the cold air from being blown out the door. It falls out fast enough as it is ;-)

If a door switch is visible in the door jamb and is not a hidden magnetic switch in the frame then with the door open you should be able to manually operate the switch to start the fan again. The lights should also turn off when the switch is operated. If there is no visible door switch then you may have to mark a blade of the fan with a marker pen etc, and then close the door and open it again about 5-10 seconds later and check if the blade has changed position indicating that the fan has operated. The fan should be operating as long as the compressor is operating.

Only suggest this as you said that frost is forming on the coils and this won’t occur if the temp is above 0 C. so the temp in the evap unit is <0 C and this is not being distributed throughout the freezer.

The caveat with all this is that there are two fans in the refrigerator for cooling purposes, one in the freezer compartment and one in the refrigerator compartment, so the freezer fan may be stopped while the compressor is running IF the control board thinks that the freezer is cold enough but not the refrigerator.

If the fan doesn’t operate at all here’s an image of the operate circuit from the control board. Disconnect the power from the fridge and then disconnect the cable on the board and test between pins 4 & 8 on the cable and also between pin 7 and the fan motor itself, should be a red wire on the fan. I don’t know what the resistance between 4 & 8 will be but it won’t be open circuit. I think that the red wire may be the fan sensor wire but I may be wrong. Anyway there should be a connection from the board to the fan on all 3 wires, and the fan motor should be between 2 of the 3 wires

Block Image

(click on image to enlarge for better viewing)

The above is just trying to eliminate another possibility, so if the freezer evap fan is OK and since you have checked the freezer temperature thermistor circuit back to the control board and it is OK, that only leaves the control board OR perhaps a sealed system problem i.e. a compressor problem or a lack of refrigerant due to a leak. Low refrigerant levels can mean that the refrigerator gets cold enough but not the freezer. Check for any oily residues on the condenser coils or under the compressor. There is a special lubricating oil mixed in with the refrigerant to help lubricate the compressor. If there is a leak anywhere, the refrigerant will escape to the air undetected but the oil will leave a trace.

You can either replace the control board (find a supplier with a good returns policy if it turns out not to be the board) and if it isn’t the board then the high/low pressures in the sealed system will need to be checked. Depending on your location, this most probably will have to be done by a licensed refrigerator repairer, due to the regulations regarding the handling of refrigerant gases that apply in a lot of places.

Fue útil esta respuesta?

Puntuación 1

9 comentarios:

Hi, I mesured it when it was disconnected across 2 wires. And that could be correct if it shows around 15°C…..

I checked again the temperature in the freezer, and now I noticed a big difference between the temperature in the lowest part (around 5°C) and the highest part (around 15°C). But still far from main board is showing (-25°C)

And still see the frost as on the last image.

- de

@katkacyt

Being colder at the bottom than at the top would be normal as cold air falls and hot air rises. Maybe it shouldn't be as much as 10 C degrees difference but there will still be a difference

Use the Ohmmeter to test for continuity from the sensor harness wire where it plugs into the connector at the back and the yellow wire on CN30 connector pin 3 on the control board. Also check that the other wire for the sensor connects to earth or to grey wire CN30 connector pin 9 on the control board.

Test with the power disconnected at the wall outlet

Something is wrong with the information from the freezer sensor. The sensor tests OK for the given temperature yet the control shows the incorrect temperature so you have to prove both the sensor wires from the sensor wiring harness connector to the control board and if they're both OK it must be in the control board

- de

Hello, I don't understand how to find corresponding connectors (pin 3 and pin 9). I looked into the document HM09 SM, but there are a lot of diagrams, so I don't know which one, and then I don't know how to localise those pins.

Is that the sensor part by PCB, numbered 7 on the page 79? The pins 3 and 9 of that connector?

- de

@katkacyt

look at p.80 Connector Layout & Description (Main Board) the orange block of connector information on the right side of the board (actually at the top of the image in the manual). pin 3 says F-SENSOR and pin 9 says GND.

Unplug the cable and measure between 3 & 9 on the cable not on the board. You should measure the sensor resistance. If you know roughly what the temperature is then the sensor's resistance should be as shown for the temperature in the table I posted above in my answer.

- de

Thank a lot for your help ☺️!!!

I measured it and it shows almost the same. Directly from the sensor it shows 7.5 and from the connector on the main board 7.2

Temperature inside is now 13.8°C o. The lower shelve, probably few degrees more on the level of the sensor.

Does it mean that it's the PCB that is broken?

- de

Mostrar 4 comentarios más

Agregar un comentario

Añadir tu respuesta

katkacyt estará eternamente agradecido.
Ver Estadísticas:

Ultimas 24 horas: 8

Ultimos 7 días: 65

Ultimos 30 días: 262

Todo El Tiempo: 7,387