atmos multi boiler unvented cyl?

[moody_gaz]

are these classed as unvented cylinders? the installer I was going to use for changing my current combi is'nt registered for unvented sytems.

 

[wnjswozo]

if its more than 15ltr stored,then unvented

 

[moody_gaz]

Its 80ltrs. Its ok I've just done a search on gas safe installers, and theres a couple of lads within half a mile of me that can do unvented.
cheers for that.