Part L - all heating installations should be part L compliant. Part L is for conservation of fuel and power and it is for this reason that heating systems should comply, to be more energy efficient.

This standard specifies design criteria for water based heating systems in buildings with a maximum operating temperature of up to 105°C.

This document specifies the requirements for the installation and commissioning of water-based heating systems in buildings with a maximum operating temperature of 110 o C and a maximum operating pressure of 6 bar. This document covers the system's requirements for the installation and commissioning of individual components of the system (e.g. heat generators, pumps, controls). It does not cover the specific commissioning requirements for these components. This document does not cover the installation or commissioning of attached systems (e.g. air conditioning, domestic hot water or ventilation systems).