It is advising consumers that all gas appliances, such as boilers, gas cookers and water heaters, need to be serviced annually by a CORGI registered installer to ensure they are working safely and efficiently and warns that appliances which malfunction are at greater risk of producing carbon monoxide.

The watchdog further emphasises its message by explaining the effects of carbon monoxide and advising the action to take if it occurs.

Nigel Dumbrell, trust manager of The CORGI Trust and chair of the Carbon Monoxide Consumer Awareness Alliance (COCAA), said: 'The temptation may be for consumers to put off having boilers or other appliances serviced because of the increase in other household bills but it is a potentially dangerous compromise. CORGI recommends that appliances should be serviced annually and that the work should be carried out by a CORGI registered installer.

'Consumers can greater reduce their risk of exposure to carbon monoxide by simple regular maintenance. A serviced appliance will also be more efficient and will ultimately save money in the long run.'

Further advice was included in the statement to help consumers ensure that the service engineer was qualified to work on their appliance.It also warned that CORGI registration does not cover all areas of gas work, so care is required to make the right person is engaged for the appropriate job..

To illustrate the dangers, CORGI states that a significant amount of work carried out by illegal gas workers has been found to have serious safety defects and an illegal gas worker is 32 times more likely to create a carbon monoxide incident than a registered installer. There are approximately 55,000 CORGI registered gas installers in the UK, the watchdog states, providing sufficient scope to engage qualified personnel.