Letters from BT Solar to solar panel owners that said customers had to book a service to “validate your warranty” were misleading, the Advertising Standards Authority says. It has told the company not to repeat the claim.

BT Solar headed its letter with a logo for the ‘British Trading Solar Association’, which the ASA said readers could mistake for a genuine trade association. It was not clear that the letter was a marketing communication.

ASA said, “We told BT Solar Ltd to make its marketing communications obviously identifiable and to make clear its commercial intent. We also told BT Solar Ltd not to claim or imply that a consumers’ warranty would be impacted in any way if they chose not to contact them.” The ASA was concerned by BT Solar’s lack of response and apparent disregard for the Code.