Does the 3 way valve actually move? It should move across and activate a microswitch at the end of the valve. If the answer is no, then the most likely cause is the whole of the valve is siezed and should be replaced. If the valve does move and activte the microswitch, then you should look to clean or replace the DHW Heat Exchanger. Replacing is usually best as cleaning may not remove all the scale build up succesfully. Hope this helps.
hawkeye2000
April 2010
howtomendit.com for free repair help, information and advice.
