Householders are being warned to be on their guard if approached about a council scheme to replace boilers.
Kirklees Council is urging people to take care after people in Mirfield, Dewsbury, Birstall, Fieldhead and Batley were approached by people claiming to be from a council-run scheme.
The council is currently not running any schemes of this nature.
A council spokesperson said: “Householders would not be approached in this manner by council staff. Anyone with concerns about callers should ask for the ID badge that all legitimate council staff wear and ring the contact details supplied for Kirklees Council to check on their identity before allowing them into their home.”