No hot water

[Booter]

Folks,

A problem has just arisen with a lack of hot water, in an apartment I have which is rented out. There's a GAS boiler which is still heating the rads OK, however not a drop of hot water. I should say that there is water coming from the taps alright, just not hot.
It has previously worked perfectly for 5 years. I'm pretty bad at diagnosing/fixing this kind of thing myself, and this is further complicated by the fact that I only get to see the place in real detail when there's a change of tenant, which might be every couple of years. So its unlike my own house where I would have fairly detailed knowledge of how it all works.
The previous tenant "legged it", and I can't help but think they have sabotaged the system in some (possibly very simple) way, however I can't find it.
Any ideas? Thanks

EDIT: Mods, didn't see the other thread before starting this one - merge if you like

 

[DGOBS]

This could be simply someone closing the balance valve on the cylinder (or a motor valve/trv gone faulty)

On your cylinder, about 6 inches up, you will see a pipe with another pipe a foot or more directly above it, that is the flow (top pipe) and return (bottom pipe) from your boiler through your cylinder coil, on the return (bottom pipe) there should be a wheel type valve, make sure this is not closed, do not open the full way as it's used to balance the cylinder, about 1/2 turns should be loads...see if that works, if not come back to us here (a pic of the hotpress pipework helps identify issues for you)

 

[Booter]

This could be simply someone closing the balance valve on the cylinder (or a motor valve/trv gone faulty)

On your cylinder, about 6 inches up, you will see a pipe with another pipe a foot or more directly above it, that is the flow (top pipe) and return (bottom pipe) from your boiler through your cylinder coil, on the return (bottom pipe) there should be a wheel type valve, make sure this is not closed, do not open the full way as it's used to balance the cylinder, about 1/2 turns should be loads...see if that works, if not come back to us here (a pic of the hotpress pipework helps identify issues for you)

Thanks Dgobs,


Tried that lower valve - its completely open, all the way. So I should close it fully, then open to 1/2 turns, correct?