TS 12355

TS 12355 is a service standard that sets out the general rules for authorised service providers who commission, repair, and maintain natural gas burning systems. Its subject is the service framework around bringing gas-fired systems into operation and keeping them in proper working condition.

What authorised service means in this context

The standard focuses on the general operating principles for organisations acting as authorised maintenance and repair services for natural gas burning systems. Commissioning means preparing the system for operation after installation, making the basic adjustments, and checking that it functions correctly. Maintenance and repair cover the work needed to preserve operating performance, correct faults, and support continued serviceability. In gas-burning equipment, these activities are closely linked to combustion behaviour, gas supply, ignition, and overall operating reliability.

Defined limits of the document

• Household heating appliances are excluded.
• Domestic hot-water preparation systems are excluded.
• Domestic cooking appliances are excluded.
• The standard addresses general service rules, not the detailed design of the equipment itself.

In general technical terms, natural gas burning systems combine components such as burners, gas lines, ignition arrangements, and control elements. The notion of an authorised service provider implies a defined level of competence and responsibility in carrying out these tasks. TS 12355 addresses that service environment, while explicitly leaving out commissioning services for domestic heating, hot-water, and cooking appliances.