The manual for the Potterton EP2002 should be exactly the same and can be obtained direct for Potterton, but TBH - It's a very basic cost and not worth the money - As they'll probably charge 50% of what the clock is worth anyway by the time it is posted.
The override is exactly what it says on the tin - It overrides either the Hot Water or the Heating... So if you run your clock in "twice" or "timed" mode, and you have it set to come on at 1700hrs... But you come home from work early, just hit the override and it will turn the heating/hotwater on straight away... Turning itself off automatically when it's time to go off...
Vice-Versa, if it's on and you press it, it goes off until it's next due to come on.
Best of luck
-> Thermgas.co.uk
ThermGas
December 2006
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