Section 9 - Solar water heating

This section provides guidance on the specification of solar water heating for dwellings.

9.1 - Scope of guidance

The guidance in this section covers solar systems with a collector area of less than 20m^2^ and solar heated water storage of less than 440 litres. It does not cover systems intended to contribute exclusively to space heating or systems providing heat exclusively to heat swimming pools. It should be used in conjunction with the guidance on water heating contained in the fuel-based sections of this guide.

Solar water heating in new and existing dwellings should meet the following conditions:

The minimum provisions for collector certification, identification and testing as specified in Table 31 (row a).

AND

The minimum provisions for selection of transfer fluid in the collector primary loop as given in Table 31 (row b).

AND

The minimum provisions for circulation pump power as given in Table 31 (row c).

AND

The minimum provisions for heat-exchanger sizing as given in Table 31 (row d).

AND

The minimum provisions for control of the system as given in Table 31 (row e). Where work is carried out in a dwelling that already has a solar hot water system it is recommended that the system control is upgraded in line with the minimum provisions for systems in new dwellings.

AND

The minimum provisions for solar pre-heated water storage as given in Table 31 (row f). Where work is carried out in a dwelling that already has a solar hot water system it is recommended that the insulation is upgraded in line with the minimum provisions for systems in new dwellings.

AND

The minimum provisions for storage of solar pre-heated water as given in Table 31 (row G).

AND

The minimum provisions for system labelling and commissioning, as given in Table 32 (rows h and i).

AND

The minimum provisions for insulating pipes in a solar primary system, as given in Table 33.

Table 31A & B

Table 32

Table 33

Table 33A

Supplementary information on solar water heating

Microgeneration Certification Scheme standard MIS 3001 Requirements for contractors undertaking the supply, design, installation, set to work, commissioning and handover of solar heating microgeneration systems.

Energy Efficiency Best Practice in Housing publications:

CE131 Solar water heating systems. Guidance for professionals, conventional indirect models.
CE51 Central Heating System Specifications (CHeSS).

CIBSE Solar heating design and installation guide.

NSAI S.R. 50-2:2012 Building Services – Code of Practice – Part 2: Thermal Solar Systems.

Glossary of standards relevant to solar hot water heating

9. Solar water heating