How to program hot water?

[djl403]

Hi and apologies in advance for a bit of a beginner's question.
I have recently moved house.
We have gas central heating, powered by a Worcester bosch Greenstar 18i boiler, controlled by two Randall TP5 room stats (2 zone system)
I can't for the life of me work out how we program the hot water (the house has an unvented WB tank) - I dont seem to be able to do it via the room stats.
Any ideas or where I should look for a separate hot water timer?
Thanks,
David

 

[Riley]

You will likely have a programmer somewhere.

 

[Scott_D]

Could be by the cylinder
Any pictures of your setup?

 

[djl403]

Thanks for your reply, I have attached a couple of photos.
I have also spoken to the previous owner who said the 'hot water is on all the time' .
This is obviously nonsense, but looking at the system/photos, what I think is happening is the tank has a thermostat and triggers the boiler when the water in the tank drops below that temp. The boiler certainly fires up if I increase the temperature on the thermostat marked A in the photo.

Whilst I think I now understand what is going on, this does seem a strange way of doing things - not had this in any other house with an unvented tank that I have lived in before. Does anyone know if this is a good thing or why it might have been set up like this?

Thanks,
David

 

[Murdoch]

It could be wired so the only control for the hot water is the tank stat

And then obviously when the water gets up to temperature the boiler will switch off

 

[djl403]

It could be wired so the only control for the hot water is the tank stat

And then obviously when the water gets up to temperature the boiler will switch off

That sounds like it. It just seems an unusual way of doing things, I was wondering what other people thought?

 

[SimonG]

Wasteful. Wants a programmer wiring in. Unless you're using hot water 24 hours a day.

 

[Anthonyjunior]

A s plan is always controlled with a programmer for both circuits.seems a bit strange to me.