Drainwater heat recovery units (DWHR) can save consumers up to 35% in water heating costs by using outgoing, warm drain water to pre-heat incoming cold fresh water. They are utilized for new construction and renovation. To ensure uniformity in product performance, CSA Group has published this standard, which specifies health and safety requirements for the durability of vertically installed, falling-film DWHR units.
A companion standard was also published -- CSA B55.1-12 Test Method for Measuring Efficiency and Pressure Loss of Drain Water Heat Recovery – which specifies requirements for measuring the heat recovery efficiency and pressure loss for vertically installed, falling-film drain water heat recovery DWHR units.
These standards verify manufacturers’ claims on system performance and to provide a level playing field for promoting their products. Consumers can have peace of mind knowing that their DWHR units are safe and durable. Additionally, performance results can now be made readily available for reference by natural gas and electric utility companies or other programs to promote DWHR systems to their customer base.
This is the first edition of CSA B55.2, Drain water heat recovery units.
This Standard specifies health and safety requirements for drain water heat recovery (DWHR) units.
This Standard was developed in response to the need for a document that specifies safety and performance criteria for DWHR units.
This Standard specifies requirements for the durability and safety of vertically installed, falling-film drain water heat recovery (DWHR) units.
This Standard applies to DWHR units of any diameter and length and configuration for use with potable water, and to their components and materials supplied by the manufacturer, their assembly and installation instructions, and their operation after assembly in accordance with these instructions. This Standard does not apply to site preparation or installation procedures.
This Standard is not intended as a design specification or as an instruction manual for untrained persons.
In this Standard, shall is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to comply with the standard; should is used to express a recommendation or that which is advised but not required; and may is used to express an option or that which is permissible within the limits of the standard.
Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material.
Notes to tables and figures are considered part of the table or figure and may be written as requirements.
Annexes are designated normative (mandatory) or informative (non-mandatory) to define their application.