Fitting Hive - gravity fed or pumped

[pavr27]

Hi, just moved into new property. As CH/HW programmer appears to have a standard back plate I have decided to install a Hive system.
However, I'm stuck on whether to set it up for a pumped system or gravity fed as I'm not sure what I have.
How can I tell?
I have a hot water cylinder in the airing cupboard (no visible pumps in there), a large cold water tank, and smaller header tank in the loft, and a boiler as pictured. What you cannot see in the boiler pic is that it has two 22mm pipes going into the top, and a 15mm into the bottom (I assume the bottom pipe is gas).
Also pictured is the wiring of the old programmer I will be replacing with the dual hive receiver.

Is my system gravity fed/partially pumped/fully pumped?

Thanks!

 

[stem]

A usual clue is that with a gravity hot water system, you cannot have the heating 'on' without the hot water being on at the same time as well.

Try turning only the hot water on. If the boiler fires up, but the pump doesn't run, it's gravity hot water and pumped central heating.

Looking at the selector switch on the back of the programmer, it looks to be set to 10, that is the setting for gravity hot water and pumped central heating. [Fully pumped should be set to 16]

Personally if it is gravity HW, I would spend the money upgrading the antiquated system to be fully pumped to make it more efficient and stop it wasting money, instead of trying to add new controls for which it's really too old to make best use of.

 

[ianmcd]

if you only have 2 x 22mm pipes coming from the top of the boiler and one 15mm (Gas) then you have a fully pumped system