Do I have a gravity system or pumped & is it C/S plan?

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I just moved into this house and can't determine which system I have. When I moved in, the programmer (I have no thermostat) was set to pumped, the CH button did nothing at all, the HW was the only button that worked heating both. I have a pump on the line coming out of the oil boiler, an unvented cylinder in a closet upstairs which from googling appears to mean I have a pumped system, I also have a single two port motorised valve that the previous owners seemingly disconnected and removed the motorised section leaving it on the ground (shown in picture at the bottom), I was initially thinking this was an S-plan system but now I'm unsure?

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I was initially thinking this was an S-plan system but now I'm unsure?
That was a normal S plan, which is all pumped. It's also reasonably modern, so forget about gravity/C plan/other, as that's all irrelevant and obsolete.
Two 2-port valves, one located towards the front of the hot water cylinder, and the heating one has been removed, disconnected from the wiring and left laying on the floor.

Given someone has obviously tampered with it by removing parts and there is evidence of a water leak on the floor in front of the cylinder, the whole lot needs to be looked at, the valve(s) replaced, a room thermostat installed and the wiring sorted so it works as originally intended.
 
That was a normal S plan, which is all pumped. It's also reasonably modern, so forget about gravity/C plan/other, as that's all irrelevant and obsolete.
Two 2-port valves, one located towards the front of the hot water cylinder, and the heating one has been removed, disconnected from the wiring and left laying on the floor.

Given someone has obviously tampered with it by removing parts and there is evidence of a water leak on the floor in front of the cylinder, the whole lot needs to be looked at, the valve(s) replaced, a room thermostat installed and the wiring sorted so it works as originally intended.
I'm confident the valve in the garage is the one I've highlighted but there should be a second 2-port motorised valve connected to the cylinder? The drain-off valve looks to be directly above the water damaged part of the wood panel, this looks to be quite old and hasn't leaked since we moved in.

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Might be worth getting a G3 registered engineer to have a look as the cylinder thermostat has been removed.
 
Might be worth getting a G3 registered engineer to have a look as the cylinder thermostat has been removed.
Sorry, that picture isn't the best, I think (from a quick google) this is the thermostat, it's on the bottom right of the cylinder but the original picture was quite dark?

If that is the thermostat, and I do have a two port valve on the cylinder, am I right in thinking if I get the valve repaired/replaced in the garage I should be able to independently turn on HW and CH? The controller is another problem, I suspect it's not wired correctly, I've added an image of that here?

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This is the hot water valve:

VALVE.jpg

The other black box with the rotary knob is the thermostat.


am I right in thinking if I get the valve repaired/replaced in the garage I should be able to independently turn on HW and CH?
Yes, but the wiring to the other items will also need to be checked/replaced.

The controller is another problem, I suspect it's not wired correctly,
There are wires in the terminals that would be expected, those being the L&N supply and the two switched outputs to heating and hot water.
However on it's own that means nothing, as there is no way to know from that photo where the other ends of those wires are connected.
The 'L' terminal also looks to be burnt/overheated, so that is something else that requires investigation.
There is also the possibility that the controller itself is damaged either due to age or because the previous persons tampering has shorted something out and destroyed parts of it.

Therefore:
the whole lot needs to be looked at, the valve(s) replaced, a room thermostat installed and the wiring sorted so it works as originally intended.
 

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