How much space required to left of radiator?

[Why Not Indeed]

Wanting to fit a very heavy, fashionable 4-column radiator fairly close to a tall cupboard:

The pipe will be coming in from the cupboard on the left as that's where the boiler is. It cannot come up through the floor as it is concrete.
What's the minimum sensible distance to leave for the plumber to able to do this job? If having the valve on the inside of the cupboard helps, then I'm fine with that.
I am not bothered about having a TRV - this is the coldest room in the house, so the times when we have the central heating on, but don't want to heat this room, are basically never.

 

[Fred Blogs]

I would just leave it for teh plumber to sort out. Bearing in mind that the valve will have to be connected I would say that that is too close.