efficient heating

Hi All New house, new boiler! The set-up is: - Vaillant Ecotec Plus 637, system boiler single plan - Tank elson zircon 250zi, no immersion - Programmer Drayton LP722 (dual channel, heating and hot water) - A Salus controller, not too sure what does is used for. As you can see from the PCB...

Hi I'm in the process of starting a yoga studio in a warehouse space with single brick wall to the outside. Room dimensions 8m x 10m, luckily I have a suspended ceiling so will help a bit, ceiling height 3m. I'm thinking gas would be cheaper but not sure if safe for a public space? Many thanks