National Trading Standards director Wendy Martin said: "Criminals are exploiting people's genuine efforts to make their homes more eco-friendly. Residents are pressurised on their doorsteps and peppered with phone calls, emails and SMS messages.
"They often include false claims about Government schemes and regulations with regard to boilers, insulation and double glazing.
"As all of us try to play our part to help tackle climate change, it's important we do so safely without being conned by criminals." Ms Martin has urged people to report suspicious approaches and take part in awareness training.