My next door neibours had one fitted and she's an OAP. I'm trying to convince her to keep it on but she's worried about the cost. How much does it cost to run a boiler?
Youe question is confusing.Watts is the power rating Efficiency means input divided by output.
boilers come in all sizes, and are heated by all kinds of fuel. The term could apply to a 500 watt water kettle, to a 50000 watt (or more) steam boiler big enough for a large building. But why do you care? what is an OAP? .
