British Gas broke into our house, say couple who owed them nothing

But it wasn't thieves who had broken into his home. It was British Gas.

The energy giant had taken the drastic - and perfectly legal - step in a row over an unpaid bill, even though it later emerged that Mr Houghton did not owe the company a penny. Scroll down for more...

The 34-year-old's nightmare began in July 2005, when he bought a two-bedroom flat in Willesden Green, North London, with his girlfriend Abby Simpson.

He immediately decided to ditch the property's contract with British Gas for a better deal with rivals EDF.

But the British Gas computer system wrongly continued to bill the couple.

Mr Houghton dealt with numerous threats of legal action and visits from the bailiffs, before a personal apology from the energy giant's managing director, Phil Bentley, convinced him that his troubles were over.

But when the couple went on a long weekend to New York in June last year, they returned home to a nasty surprise.

While they were away, British Gas had swapped their meter for a pay-as-you-go version.

To do so, an engineer and locksmith had sneaked into the flat by picking the locks on the front door and an internal door.

They then left a note informing the couple what they had done.

British Gas switches customers to pay-as-you go meters if they consistently fail to pay their bills.

Investigators have since worked out that it was the occupants of the next-door flat who owed the money to British Gas.

The company has now apologised, blaming the bungle on incorrect records at the National Grid and problems with the address at Royal Mail.

It has also given Mr Houghton and Miss Simpson £200.

However, the watchdog Energywatch last night demanded that the gas supplier fully compensate the couple.

Mr Houghton said: "I am totally disgusted and bewildered by their behaviour.

"I spoke to manager after manager at their call centres and each time was promised the problem had been sorted out."

Between 2005 and the break-in two years later, the bill demands rose from £90 to £900.

Mr Houghton said: "We sent them letters in response but then the bailiffs came round trying to get access."

A spokesman for the company claimed last night that the Gas Act allows workers to break into a customer's home to change the meter, providing he or she has been warned in advance.

However, Mr Houghton claims he was never notified.

He added: "It felt so intrusive that they had been in our flat and could have gone into every room if they'd wanted to.

"I called the police, who said they weren't interested because nothing had been taken."

Graham Kerr, a spokesman for Energywatch, said: "Mr Houghton and his partner have had appalling treatment from British Gas.

"Having your home broken into is a traumatic experience and that blow isn't softened by the perpetrator being a household name that just happened to make a mistake."

A British Gas spokesman said: 'Our managing director, Phil Bentley, has spoken to Mr Houghton and apologised.

"We've since corrected our records, changed the meter back and Mr Houghton has been given £200 in compensation."