Mine was a real mess, and all I could do was work out where each cable went, and re-wire. The heating engineer admitted he would not have known where to start, but for me, it was an interesting project.
I also have a relay. In the main, the motorised valve acts as a relay, but I wanted the pump and boiler independent, so needed two sets of contacts, and there is only one set in the motorised valve.
This is not the final plan, but this is how I slowly built up a plan of how it all worked
View attachment 395327it took time, and I started in April so finished by the time the winter arrived.
So after all that work, it not really worthwhile heating DHW with the oil boiler, and my boiler heated the house and the flat independently, which was why mine was complex.
So I would have a look at how it works now, if working near enough, then leave it until the summer.