When looking at the instructions for fitting a domestic AC unit I found This would as I read it mean a type B RCD, which presents some problems, one is you can't get a single module width RCBO better than type A for most consumer units. So to fit a type B in the main means a separate enclosure, and the consumer unit would need a MCB fitting and no RCD protection to the auxiliary enclosure which means either a high integrity consumer unit or all RCBO consumer unit to be able to convert to have a non RCD protected supply to the auxiliary unit. It seems type B RCD's are often three module width, and very expensive, between £120 and £700, and even then are often only rated at 40 amp, to retain type testing it needs to be same make as consumer unit it is being installed in, which also presents problems. The The AC in question installer reference guide this is fortunately not my problem, it is not my AC or my job to fit it. However it is possible any one of us could come across this in the future, so seems good idea to talk about it before the event so we can advise a customer. To my mind no domestic appliance should require over a type A RCD, simply down to you can't get better than a type A RCBO for a consumer unit, commercial not limited to using type tested consumer units so not the same problem, but an electric car charging pod can have everything built in so can be supplied from a type A RCBO, so no reason why any other appliance should not be the same. I have heard the Tesla charging pod does not have the equipment built in to be able to be supplied from a type A, personally I would say in that case not fit for purpose. But what does the team think?