Drain water 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 requirements for measuring the heat recovery efficiency and pressure loss for vertically installed, falling-film DWHR units.
A companion standard was also published -- CSA B55.2-12 Drain Water Heat Recovery Units – which specifies requirements for the durability and safety of 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 B55.1, Test method for measuring efficiency and pressure loss of drain water heat recovery units.
This Standard specifies requirements for measuring the heat recovery efficiency and pressure loss for vertically installed, falling-film drain water heat recovery (DWHR) units.
This Standard applies to DWHR units
(a) of any diameter and length;
(b) with a configuration where potable water and drain water flow rate is equal; and
(c) with a flow rate range of 5.5 to 14 L/min.
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.