how do i fix my overheating ariston 1237?

yes most likely the thermostat or thermistor(NTC).
Round item, located on rear face of drum, approx 2 inches across.
Spares suppliers:
www.4directelectricals.co.uk
http://www.ukwhitegoods.co.uk
www.ukapplianceparts.com
http://www.domesticspares.co.uk
http://shop.ezee-fix.co.uk
http://www.espares.co.uk

or simply go into google and type in "washing machine spare parts" - selecting "pages from uk".

If you are familiar with ebay, there are dozens of sellers running washing machine spare parts shops at very competitive prices.

Repair and service your own washing machine. Go to www.2ndwave.co.uk/manual.html

dannyboy
October 2008