Bogus salespeople have been pretending to sell double-glazing on behalf of Wakefield Council.
Cold callers claiming to offer cheap windows have been knocking on doors in the Flanshaw area.
But the council’s Home Energy Team said the claims were false.
Coun Denise Jeffery, the council’s cabinet member for regeneration and economic growth, said: “People need to be aware that uninvited callers selling double glazing schemes are not endorsed by the council.
“We will always inform you first if we are sending someone to your home - so if you are not expecting us, then please ring and check.”
People can check the legitimacy of visits from the Home Energy Team by calling 08449 020 222 from Monday to Friday between 9am and 5pm.