BS 5864:2019 Installation and maintenance of gas-fired ducted air heaters of rated heat input not exceeding 70 kW net (2nd and 3rd family gases). Specification

BS 5864:2019

Installation and maintenance of gas-fired ducted air heaters of rated heat input not exceeding 70 kW net (2nd and 3rd family gases). Specification

Status : Current   Published : February 2019



BS 5864:2019 also available with tracked-changes. To learn more and buy, click HERE. 

Tracked-changes versions of Revised Standards 

This year, BSI is offering tracked-changes versions of key standards that have been revised, to help users see clearly what's changed and what's stayed the same. BSI is pleased to say that BS 5864 can be bought as a simple standard or as a 'tracked-changes package' where customers receive both the new standard and a tracked-changes version. See the tracked-changes standard here.


What is this standard about?

This British Standard covers how engineers should choose, install and maintain certain types of gas-fired warm air heater, specifically in accordance with the EU’s Energy Related Products Directive.

Who is this standard for?

  • Related training centres
  • Installers
  • Service engineers
  • Manufacturers
  • Notified bodies
  • Test houses
  • Department of Communities and Local Government – Building Regulations
  • Organizations which carry out work on behalf of government in support of Building Regulations and the Standard Assessment Procedure
  • Trade bodies – e.g. The Institute of Gas Engineers and Managers
  • Gas Safe Register
  • End-users interested in their warm air heaters and installation

Why should you use this standard?

This is the only recognized industry standard for the installation and maintenance of gas-fired warm air units. Its purpose is to help engineers safely install warm air heaters, particularly in accordance with the new EU Energy Related Products Directive.

The standard specifies requirements for the selection, installation and maintenance (see Note 1) of flued, gas-fired, ducted-air heaters of rated heat input not exceeding 70 kW, based on net calorific value, burning 2nd or 3rd family gases to heat one or more rooms or internal spaces in either domestic premises (see Note 2) or commercial premises.

It applies to warm air heaters that incorporate a fan to circulate the warm air, to combined air heater/circulator installations and to the servicing and maintenance of heaters that distribute warm air by natural convection.

The standard doesn’t apply to gas installations in towed or motorized leisure accommodation vehicles.


NOTE 1: For the purposes of this standard, installation includes design, inspection and commissioning. It is recognized that each of these tasks can be performed by the same person.

NOTE 2: As well as normally constructed dwellings, domestic premises include any permanently sited leisure accommodation vehicles, residential park homes and permanently moored boats.

NOTE 3: For the purposes of this standard, heat input is expressed in terms of the net calorific values (CV), unless stated otherwise. The ratio of gross to net heat input is approximately 1.11:1 for natural gas, 1.09:1 for propane, and 1.08:1 for butane.

NOTE 4: It is essential that persons carrying out the installation of any gas appliance be competent to do so. Annex A gives information about the legal requirements which relate to the competence of approved operatives.

What’s changed since the last update?

This standard replaces BS 5864:2010 which is now withdrawn. It is a full revision which introduces changes to:

  • Clause 4 Competence (including three principles for installation)
  • Clause 5 Environmental considerations (in four key areas: Disposal/recycling of existing appliances and systems, Disposal/recycling of the new appliance and system components packaging, Optimization of energy usage through appliance selection and system design, and Minimization of harmful emissions discharge
  • Clause 6 (Selection of equipment and pre-installation) and new specifications on condensate.

Standard NumberBS 5864:2019
TitleInstallation and maintenance of gas-fired ducted air heaters of rated heat input not exceeding 70 kW net (2nd and 3rd family gases). Specification
Publication Date28 February 2019
Normative References(Required to achieve compliance to this standard)BS 5440-1:2008, BS 5440-2:2009, IGEM/UP/7:2006, IGEM/UP/2:2008, BS 5871-3, PD 5482-3, BS EN 50379-3, BS 5482-1, BS 476-22, BS EN 1949, BS 5546, BS 6891, BS 7671, BS EN ISO 10239, BS 5482-2
Informative References(Provided for Information)BS EN 1856-1, BS EN 721, CIBSE Guide B3:2002, Building (Amendment) Regulations 2009, Gas Safety (Installation and Use) Regulations 1998, BS EN 12831-1, Gas Safety (Installation and Use) Regulations 2018, Building (Scotland) Amendment Regulations 2007, IGEM/UP/17:2011, BS 3632, GSR TB 087:2009, Health and Safety (Gas) (Guernsey) Ordinance 2006, BS EN 778, Building (Isle of Man) Regulations 2007, Building (Northern Ireland) Amendment Regulations 2009, Asbestos (Prohibitions) Regulations 2003, IGE/G/5:2009, BS 5588-1, Water Supply (Water Fittings) Regulations 1999, BS 7967, GSR TB 007:2010, DD 221, GSR TB 008:2009, IGEM/UP/18:2012, Gas Safety (Application) (Isle of Man) Order 1996, Gas Appliance (Safety) Regulations 1995, BS EN 1319, Building Control Act (Isle of Man) 1991, BS 6798, Gas Safety (Installation and Use) Regulations (Northern Ireland) 2004
ReplacesBS 5864:2010
Draft Superseded By18/30375326 DC
DescriptorsSelection, Commissioning, Siting, Ratings, Maintenance, Gas space heating, Ducts (building services), Household equipment, Heaters, Fan-assisted warm-air heating, Heating equipment, Flued heaters, Gas-powered devices, Heat, Installation, Central heating, Domestic, Thermostats, Warm-air heating, Air heaters, Inspection
ISBN978 0 539 00422 9
File Size1.796 MB

 Your basket
Your basket is empty

Multi-user access to over 3,500 medical device standards, regulations, expert commentaries and other documents

Develop a PAS

Develop a fast-track standardization document in 9-12 months


Access, view and download standards with multiple user access, across multiple sites with BSOL

Worldwide Standards
We can source any standard from anywhere in the world

Customers who bought this product also bought

  • BS 6400-2:2018
    Specification for installation, exchange, relocation, maintenance and removal of gas meters with a maximum capacity not exceeding 6 m3/h Medium pressure (2nd family gases)