Troubleshooting and fixing a Hotpoint RL78P Larder Fridge

Maybe not the most gripping of subjects, but when it's your beer fridge, it becomes very serious...

In these COVID-19 times, Google and YouTube are your friends.  This is a larder fridge that the girlfriend (now wife) and I bought nearly 20 year ago, and it's served is well ever since then, with nothing going wrong through two children and two house moves.

Now relegated to the basement and with sole purpose of keeping wine and beer cold (is there a worthier calling for a fridge), about a week ago, I came to get a beer, to be greeted by the light being on, but the beer wasn't cold.

At least the light being on was somewhat of a positive, there was at least electricity coming into the fridge.  Having found the model number (open the door and look under the top sill), I couldn't find any specific help for this model or even the instructions.

Reverting to the generic Hotpoint advice, the first two tips were broken thermostat, or condenser.  As the condenser is not user servicable or cheap to replace I set about trying to check if the thermostat was faulty.

I found this video on Espares on replacing a thermostat :

It looks pretty simple, but there a catch on this fridge, in the video the thermocouple (long thin wire) isn't attached to anything.  ON the RL78P it is screwed to the back of the freezing panel, so this needs to be disconnected before you can remove the thermostat.

Here's another Espares video showing how to test a thermostat with a multimeter

I had to do test it a couple of times, as sometimes it appeared to be fine others not, but as it was either try replacing it (£40) or get a new fridge (£200) it seemed worth a shot.  So after not being able to order from Espares (I had a problem with their payment gateway, which was a shame as I'd rather have given them my money as their advice had helped me troubleshoot the problem) I had to revert to the Hotpoint spares site, where the part was actually cheaper.

A couple of days later the new one arrived :

I also found someone (dreeks55) had written some decent instructions on replacing the thermostat on this model, which I have slightly amended as below :

1. PARAMOUNT - SWITCH FRIDGE OFF AND UNPLUG IT FROM THE MAINS!!! 
2. Decant everything plus the shelves - you will need the room. 
3. On the right hand side just above midpoint is a lozenge-shaped housing which contains lamp/thermostat and lamp switch. 
4. To gain access to the thermostat, locate the cleverly hidden fixing screw - there's a small grey prise-out disc just to the right of the control knob. 
5. Unscrew that and the housing should release when you draw it back - gently! There are locating tabs on the housing which slide into slots in the lining. 
6. Remove the Thermostat dial, and unscrew the retaining nut from the thermostat spindle and release . 
7. Now take a photo of the wiring connectors on both the thermo and the lamp switch. Disconnect all leads to these components (no need to touch the actual lamp connectors). You WILL need this diagram when re-connecting new thermo. They are marked with numbers, on mine it was 3 and 4

Old thermostat still connected (white metal cable is the thermocouple)
8. Now unscrew the 3 retaining screws on the freezing panel at the back of the fridge - be VERY CAREFUL when you pull it forward and to the left to give you access to the thermocouple end. The thick pipe attached to the panel contains the coolant fluid. The pipe is flexible enough to withstand moderate movement. 
9. There should be two screws and a plastic fillet securing the thermocouple to the panel. 
10. Unscrew the screws (remembering to keep the screws in a container - easily lost under the fridge!!). 
11. The new thermocouple can be bent into a U just like the defective one. Fit the new thermostat by reversing the removal instructions. 
12. Good luck - patience is a virtue

New thermostat during fitting, you can see I've not reattached the new thermocouple yet

It was quite straightforward, only the bending of the freezing panel and pipe causes raised nerves, as if I'd broken that not only would there be coolant everywhere, but it would have been game over.  It seemed quite sturdy and I had to move it a couple of times, but all went well.  Probably took about an hour to diagnose, and half an hour to refit the new thermostat, but best of all I've saved £150 and now have cold beer again !

hope this helps