Conservation of fuel and power: Approved Document L, Volume 2 — Buildings other than dwellings

L1(b), L2 O N L I N E V E R S I O N Table 6.8 M inimum COP for heat pumps in new and existing buildings Heat pump type Minimum COP (at rating conditions in BS EN 14511-2) All types (except air-to-air with output ≤12kW, absorption 2.5 and gas-engine) for space heating(1) All types (except absorption and gas-engine) for 2.0 domestic hot water heating Absorption 0.5 Gas-engine 1.0 NOTE: 1. For air-to-air heat pumps with an output ≤12kW, follow paragraph 6.44. 6.45 In addition to the general guidance for zoning and controls in Section 5, any outdoor fans, including those in cooling towers or dry coolers, should be controlled. 6.46 For heat pump installations in which there are other heat sources available to the same building, each of these heat sources should be appropriately incorporated into a singular control system. Mechanical ventilation 6.47 The specification of ventilation systems should be based on the ventilation needs of the building, in accordance with Approved Document F, Volume 2: Buildings other than dwellings. 6.48 Air handling systems should be capable of achieving a specific fan power (SFP) at 25% of design flow rate no greater than the SFP achieved at 100% design flow rate. 6.49 Fans used for general air distribution that are rated at more than 1100W should be fitted with variable speed drives. 6.50 Ventilation ductwork should be made and assembled so as to be reasonably airtight. Ductwork should comply with the specifications in either of the following. a. BESA’s DW/144. b. BS EN 1507, BS EN 12237 and BS EN 13403. 6.51 Air handling units should be made and assembled so as to be reasonably airtight. Air handling units should comply with Class L2 air leakage given in BS EN 1886. 6.52 The specific fan power of air distribution systems at the design air flow rate should be no greater than in Table 6.9, as adjusted by the appropriate factors within this table. Specific fan power should be calculated in accordance with BS EN 16798-3 at the full design load. For fan coil units, use BS 8850. 50 Approved Document L Volume 2, 2021 edition Building Regulations 2010 O N L I N E V E R S I O N