There has been a significant increase in calls to Denbighshire County Council regarding people knocking on doors offering free replacement boilers, heating systems or loft insulation.
Denbighshire County Council says it is not working in association with any organisation to knock on doors offering free boilers.
"These organisations are not working on behalf of the council, we do not condone or associate with any organisations that are cold calling," said a spokesperson.
The spokesperson added: "It is possible that you may be able to receive funding towards heating system improvement and/or insulation as Denbighshire County Council have published our Local Authority Flexible Eligibility statement of intent.
"If you have a house that is F or G rated on the Energy Performance Certificate or is E rated and you meet one of the additional criteria then you may be eligible for funding if the house is privately owned or rented (not social).
"The official route is to call North Wales Energy Advice Centre: 0800 954 0658."
Councillor Tony Thomas, Cabinet Lead Member for Housing, Regulation and the Environment, said: “The council does not condone cold calling but we do have a policy in place that can assist residents to access ECO funding that can improve the energy efficiency of their house. They can do so by calling North Wales Energy Advice Centre”.
"Anyone concerned about anybody in the neighbourhood knocking on the door offering to carry out home maintenance work, should make a note of vehicle make, model, colour and registration number and any descriptions of the individuals, and contact either the police on 101 or Trading Standards via the Citizens Advice Customer Service on 08454 04 05 06 or for the Welsh Language Service 08454 04 05 05."
Anyone feeling threatened or intimidated by any doorstep seller you should shut the door and call the police emergency number 999.