If your using the programmer for hot water, it depends where the four wires are coming from.
Normally you have a constant live and neutral, and then a switched pair.
The live and neutral power the Drayton programmer (first and second terminal on the left), and when the hot water is required the switched pair make contact (on the furthest right terminals normally marked 4 and 4), which causes the call for hot water.
Please let me know if you need any further assistance, and also advise of the exact model of Drayton programmer.
I just wanted to follow up and see if you needed any further assistance?
Good morning Paul, I just wanted to follow up to see if you need anything else, and ask you rate the service received using the star rating on the page.
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