Ecoheater 1500mm Slimline Greenhouse & Shed Heater HHT315 (190W)

can I use this heater from an extension?

I'm looking for a heater to keep the loft from going below freezing. It gets really hot up there. Would this do the job or is there a better one?

I have a pub shed, will this keep me warm while sittjng in there in autumn weather?

can you place it vertical aswell as horizontal