can i fix my kenwood 901?

My thanks to your website and to John H for his thorough advice. My family's Kenwood Chef started smoking while doing tough work kneading dough. I found a burnt out component, quite unrecognisable, which I could deduce from John's information was a 56ohm 2W resistor. Among my odds and ends I found six 330ohm carbon resistors, which I connected in parallel to obtain 55ohm, of adequate wattage. This small assembly I soldered into place taking care not to overheat the triac. There is plenty of headroom under the hood. The machine now works fine and the repair cost nothing! But if it goes wrong again the kit at Ebay sounds a good idea.

Tony D
January 2009

The part you have identified does not have the word "RITA" thereon, but "RIFA". It is in fact an EVOX RIFA capacitor. There are two of these capacitors in the circuit for speed control on A901 Chef.
After 20 odd years some/most of the electronic components on the Chef fail and need replacing. If you are handy with a soldering iron it's an easy job of removing the original parts and replacing with the new parts, thereby restoring your machine back to life for only a few pounds. The parts you require are as follows:-
Class X2 Capacitors:-
0.15uf (same as 150nf)
0.047uf (same as 47nf)
Triac:-
BTA08-600B
Resistors:-
56 ohm (same as 56r) 2 watt resistor
220 ohm (same as 220r) 2 watt resistor
Most of the above parts can be obtained via Maplin apart from the 56 ohm 2 watt resistor and the 0.15 uf X2 capacitor. However, you can 'make up' the preferred capacitance by using a 0.1uf capacitor in parallel with another 0.047uf capacitor (from Maplin) giving you a potential of 0.147uf capacitance which is as near as possible to the original capacitors value of 0.15uf. In parallel means that one capacitor is "piggy backed" on top of the other and corresponding legs soldered together (and not "daisy chained").
Therefore you can get most parts from Maplin- you may find the 56 ohm 2 watt resistor advertised on Ebay or get all your replacement parts from another electronic component supplier. Another option, is again Ebay, where someone is selling all the parts for a "901 motor repair kit" for about a tenner. I think this seller also includes two "spark suppression" capacitors- which are probably not needed as the originals last longer than the other components (appropriate replacements would be 1nf Class Y2 ceramic disc capacitors). In your search for the 56 ohm 2 watt resistor do not be tempted to use a lesser wattage resistor- it will "blow". You MUST only use X2 capacitors and Y2 capacitors, as above, as they are designed for use with mains voltages.
If you search hard enough, you could probably obtain all the parts a bit cheaper -in reality the five parts you need are only worth about £2- you may find that the Ebay vendor is a convenient option to get all you parts in one go. Do not be tempted to replace only individual parts- replace all five parts. (If you go down the Maplin route you will need two 0.047uf capacitors).

John H
January 2009