Question to the Department for Business, Energy and Industrial Strategy:

To ask the Secretary of State for Business, Energy and Industrial Strategy, pursuant to the Answer of 11 June 2019 to Question 258964, how the variable features of a household heating system described in that Answer affect the efficiency of the boiler rather than the heating system.

Condensing boiler efficiency is affected by water return temperature to the boiler. The design, efficacy and maintenance of the heat distribution system can impact this temperature. I refer the hon. Member to the answer I gave him on 25th June 2019 to Question 266061 for further details.