Heating debate | Accordion crimes | Political uniforms | Is sport the new rock’n’roll? | Bittern song

Tim Bradley (Letters, 1 October) and Adam Halawi (Letters, 7 October) are comparing apples and pears. Most heat pumps in the UK are used to heat water for radiators or underfloor heating. Tim’s heat pump is heating air that is being ducted throughout his Swedish property. Assuming his ducting was already in place, all that would have needed changing was the heat source. But Adam’s radiators will need replacing with larger units due to the lower operating temperature, and I suspect his insulation will need upgrading.
David Anson
Sheffield

• Your report (Squeezed out: last accordion maker in France to close shop after 105 years, 5 October) reminded me of the definition of a gentleman: one who can play the accordion, but doesn’t.
Dr Richard Carter
Putney, London