What is the eco-mode setting on a boiler? is it cheaper than the normal function? I was able to schedule a time that was convenient for me they arrive about min early which was fine they introduced themselves and then wanted to be shown where the... Smart controls can help with that in fact, you could increase your boiler’s efficiency by an extra %! pretty nifty, eh? Looking for genuine baxi boiler spare parts in stock, available for immediate dispatch? welcome to the ‘home of stock’ where.