it sounds like you require a new resistor pack for the fan switch. different resistors produce different speeds. if the resistor pack is damaged then the current will have an un restricted path. hence why you only get the quickest speed.
Andy
April 2009
apparently the setting 4 works on full power so bypasses the resistor , 1 2 3 all work through the resistor which lowers the voltage to give you a lower speed on the fan. get it fixed because i didnt find this out in time and due to the heater being on full power all the time it burnt out.
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