Trading Standards teams across the north are reminding householders to be on their guard if they are approached by people offering to install home energy products.
This follows recent reports of traders in the area, offering free insulation works under government-funded schemes to properties without the formal approval required.
Trading Standards teams within Orkney Islands Council, Highland Council, Western Isles Council, and Shetland Islands Council have all received such reports.
A council spokesman said: “This is a complex market and there are many home energy grants available to householders to have products such as roof or wall insulation, boilers or solar systems installed for free, some even offering future payments.
“This has led to an increased volume of complaints over the last few years from householders who feel they have been misled on their doorstep when they realise what they have got is not necessarily what they thought they were getting.
“Also, it is an offence for any trader to claim to operate under such a scheme without the appropriate approval or authority.
“I’d urge any householder to check first the validity of any scheme, product, installer and payment before entering into a contract, whether it is free or not.”
The councils involved are currently working with installers to deliver energy efficiency improvements to properties.
Householders can also receive free and confidential advice if they feel that they have become a victim of an energy scam by contacting Consumeradvice.scot on 0808 164 6000 or alternatively by email at advice@consumeradvice.scot.