Ok, so we have an air source heating system which has to be serviced annually (apparently) and we booked an engineer to do this at the hefty sum of £120 plus VAT. He not only arrived 3 hours late but proceeded to talk non-stop at DH trying to sell us other things we haven't needed before. He managed to make this last an hour. Then he fiddled around with the outside fan, removed some black bits from the filter, didn't replace the filter which we thought was a basic necessity and promptly left with the promise of quoting us for this lagging we haven't needed before now. AIBU to think this is a complete rip off? Should we refuse to pay? And does anyone know if these air source systems really need annual servicing? I'm sure DH could do what he did no problem and save us £150!