In this case, the residents were the creatures that were living, or had been, under our fridge. We have a built-in fridge of indeterminate ancestry, probably early 1990s, which preserved its anonymity behind a pine door in a row of kitchen units. I eventually found the model plate and it is a Tricity Bendix BL501W larder fridge, which seems to be an obscure one when it comes to getting info.
The fridge came with the house so there is no documentation. As long as it was working, we left it alone, but this turned out to be a mistake. There is no free convection round these for the condenser to lose heat, so the tubes are ventilated by a tangential blower of the type once common in fan heaters - a small induction motor driving a squirrel-cage centrifugal fan about 180mm long and 60mm diameter. I was vaguely uneasy about the fact that the fridge had been in-situ for at least sixteen years without anyone cleaning the fluff out of the coils and latterly it seems to have spent more and more time running rather than resting. This was brought to my attention because of the increasing noise from underneath caused by the fan module rattling, and it was obvious that the fan was out of balance and probably had worn bearings. Eventually it got to the point where it was banging and only intermittently (although the compressor was still running normally) and I decided that Something Had To Be Done.
Getting access was easy - if I had known how easy, I would have done it years ago! It was screwed to the next cabinet by a bracket with another screw vertically into the worktop above, and a third screw by the top hinge (opposite, on the right in this case). Removing the plinth board from the run of units revealed the most disgusting assortment of dead creatures, live insects and spiders, dust, rotten food, lost implements and even a pile of sand placed by an invading ant colony some time ago. I had to plunge my hands into this lot to lower the adjustable feet, to allow the fridge to slide forward and out. Cleaning out the cavity took another hour.
It was handy to be able to prop the fridge on a support, leaning backwards. The fan module is visible at the front through a clear plastic window which is held in place by two small screws and slides out. Additionally there is a sliding tray at the side which comes out to reveal the bottom of the condenser coils. Other than that, the whole bottom tray is a single plastic moulding with the compressor and other bits fixed in it (and connected by copper pipe to the compartment) so no further dismantling was possible. Inside the coil chamber was a mat of greasy fluff and debris which virtually blocked the whole air passage.
Examining the fan, it was clear that the rotor was completely free at one end and it was obvious that the bearing had disappeared. These things are very simple and have only the motor spindle supporting them at one end and at the other end the shaft is running in a graphite sleeve bearing - a graphite bush with a metal thrust plate moulded in, the whole bush being supported in a very flexible rubber grommet in the pressed steel chassis. In fact the graphite bush was still there, but had worn oversize to the point where it didn't show in its housing. I gloss over the half an hour it took to work out how to get the fan module out of its rubber mountings and extricated through the front opening - I had to use a big screwdriver and a big pry bar to lever it out of the moulded tray, bending the mounting lugs on the way. If there's an easier way, please tell me.
Unfortunately it seems that these fans are not as common as they used to be. The only place I could find them (without troubling the Electrolux service people, as I don't want to be laughed at) was at Catering Parts UK, whose model TAS18R seems to be suitable. Unfortunately it's also £32, which isn't viable as we will probably only need this fridge for a few more months. So the next step was to find a bearing - also with no success. In the end, I selected a small piece of old oak, which is very hard, and turned a new bush on the lathe. I have successfully used old oak bearings before, in a kids' scooter, and it has been running for over five years with no obvious wear. You do need to grease it first though. The oak sleeve fitted the grommet OK but I had to fill the grommet with silicone sealant, as the rubber was perished and began to fall apart. After a suitable curing period, the oak bush was greased and put in place and the fan reassembled, and works perfectly with a very smooth action.
I had to repair some of the door frame which had been kicked to bits, and clean off a horrible mess of cheesy layers and fungal growth where spilt milk had been trapped in the fascia, then it was time to force the fan module back in. I eventually succeeded, and the fridge is now back in use and running quietly. Very quietly in fact, because I haven't seen the fan rotor move since installation. The fridge is maintaining temperature correctly, the condenser barely gets warm and I don't know whether the fan is off because it simply isn't needed or whether I have knocked off a wire during the violent re-installation. At the moment I'm not going to investigate further, as everyone is happy and the dog can sleep undisturbed at night. But it keeps nagging away at me, and maybe next year I'll pull it out again just to see if I did screw it up.
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