Gary Coombes, 58, of 20 Quantock Way, Wembdon, Bridgwater, pleaded guilty to seven counts of fraud at Taunton Crown Court and was ordered to pay the couple £8,000 in compensation.

The court heard that Mr Coombes, who traded as Bridgwater Heating, targeted the couple and repeatedly visited their Bridgwater home over a five year period.

He grossly overcharged them for boiler service and maintenance work, as well as general home maintenance.

It was only when the victim’s daughter became suspicious and reported Mr Coombes to Heart of the South West Trading Standards Service (HotSWTSS), that the fraud was uncovered.

Trading Standards officers found that much of the work was unnecessary and not completed.

On sentencing Judge Zeb told Mr Coombes: “On each occasion you excessively overcharged, and rendered invoices that were grossly overinflated, false, and not reflective of the work required or done.

“In all that time, [the victims] came to know you, trusted you, and paid without question.”

She said that both were elderly, and the male victim was a carer for his housebound wife: “It was dependent on you to conduct works honestly and at a reasonable cost. This couple had vulnerabilities that you prayed on repeatedly and caused them financial harm and stress.”

In mitigation she acknowledged his guilty plea and that he had started to save towards the compensation payment.

Sharon Anderson, Group Manager Investigations & Compliance for Heart of the South West Trading Standards Service, said: “If you’re looking to have work done then Trading Standards always advises you get a range of quotes from reputable traders either through recommendations from people you trust or through an approved trade scheme such as the Trading Standards run Buy With Confidence approved trader scheme.”