when you turn on the tap it should lift a diagphram in the diverter valve and hold it , look from under the boiler after removing the bottom panel ,if fitted, . you will see a black plastic box on the end of the brass diverter valve ,when you turn on a tap the plunger on the end of the valve should come out and contact with the micro switch in the box and hold it,if it falls back then you need a new diagphram fitted to the valve.
If you need to find a tradesperson to get your job done, please try our local search below,
or if you are doing it yourself you can find suppliers local to you.
Select the supplier or trade you require, enter your location to begin your search.
Please select a service and enter a location to continue...
Are you a trade or supplier? You can create your listing free at DIYnot Local