A plumber from Derbyshire could face up to six months in prison and a £20,000 fine after leaving a house at risk of a 'lethal' explosion.
Mark Austin, who posed as a registered gas fitter, used the wrong pipes while installing a new boiler and gas hob at the property in Sneyd Green.
He also certified the gas systems of more than 20 rental properties on behalf of Robert Birchall, of Newcastle-based Birchwood Homes, despite not being qualified to do so.
The 40-year-old pleaded guilty to three charges of carrying out gas work while not appropriately registered, two of falsely claiming to be appropriately registered and another charge of installing an appliance that was inherently dangerous.
Stafford Magistrates' Court heard Austin, who traded under the name Austin's Plumbing Services (APS), had been prosecuted by the Health & Safety Executive (HSE) after his shoddy work was exposed.
An inspector was sent out after the tenant, Miss Miller, grew concerned and called the Gas Safe Register.
The inspector found several defects and identified that the pipes used by Austin were too small, and could not supply gas to the hob and boiler simultaneously.
This meant that if the boiler came on while the hob was in use, the gas supply to the hob would cut out. When the boiler went off the supply would then return to the hob, which would no longer be lit, therefore allowing gas to escape and creating the risk of a serious explosion.
Steve Lee, representing Austin, said his client had believed he was correctly registered as a gas fitter after completing training with a friend.
However Austin was later contacted by the Gas Safe Register and the HSE and told he was not registered, yet continued to work claiming he was.
Mr Lee said Austin had been drinking heavily at the time after his marriage broke down and 'was not thinking straight'.
Magistrates adjourned his sentence until 8 June to allow a pre-sentence report to be prepared by the Probation Service. Should the case be committed to crown court, he could be jailed for up to two years and face an unlimited fine.