White Knight Tumble Dryer DRAFT

Here are some notes on problems and fixes I've encountered with our White Knight tumble dryers.

PLEASE NOTE THAT INCORRECTLY MAINTAINED TUMBLE DRYERS CAN BE LETHAL. 240V, water, heat and moving parts make for quite a few hazards, so don't make any fixes yourself without proper training.

We originally bought a White Knight 'A' class CL847AW, which has moisture sensing built into the drum, and an extra slow setting which takes four times as long as normal to dry clothes. This allows it to achieve a very good efficiency rating. The first time we used it we didn't think it was working because it didn't heat up and the clothes were still wet after a few hours. Once we got the hang of it though we found it worked well and used it for several years without problem.

First problem we had was that it stopped turning, on investigation I found out that the brush which presses against the top of the drum had come loose. It is in the middle of strip of metal attached across the top of the dryer, with chunk of soft metal pressed by a spring against the drum. This seems to be part of the moisture detection circuit, so since the brush wasn't making contact there was no current, hence no moisture detected. Fitting it back with a slightly stronger spring fixed the problem.

Next problem after another few years was a rumbling noise when drying, and a few months later we noticed some clothes were torn. On investigation, the problem was with the front bearing, which holds the front of the drum away from the front cover of the dryer. Since the drum was now rubbing against the cover the metal had now broken away, and was tearing clothes. This was a disappointment, since it looked as though fixing the bearing straight away would have avoided any problem.

I picked up a broken White Knight tumble dryer, a SensorDry WK427 with the intention of using the drum as a replacement. However, it turned out that the drums were quite different due to the moisture sensors which are fitted in the drum itself, but which are not fitted on the WK427. Luckily I was able to fix the replacement tumble dryer instead, which had two problems: - No heat. This turned out to be a problem in the control module which I was able to work around by using a different pin for the heater coil. - Loud rumbling noise while drying. This was due to a loose fan which pumps the air out. This fan is attached to a shaft from the drive motor, but had come loose. It also meant that no air was being driven through the machine, so clothes would not dry. First attempt was to use araldite to fix the fan back onto the shaft and refit the spring clip, but this came loose again after a few weeks. So I used the motor assembly and fan from our original dryer instead, and so far that's worked fine for about a year so far without any problems. The fan is screwed to the shaft on this one rather than using a spring clip, so looks like Crosslee have improved this design.