Performance standard for rating water-chilling and heat pump water-heating packages

Designation Number:
CSA C743
Standard Type:
National Standard of Canada - Domestic
Standard Development Activity:
New Edition
ICS code(s):
91.140.30
Status:
Proceeding to development
SDO Comment Period Start Date:
SDO Comment Period End Date:
Posted On:

Scope:

Note: The title and scope for this NOI (originally published on October 19, 2021) was updated by the responsible SDO on January 21, 2025.

1.1 Inclusions 

1.1.1 Vapour compression water-chilling and water-heating packages 

This Standard applies to factory-designed and prefabricated vapour-compression water-chilling and water-heating packages that include one or more compressors as well as 

  1. water-cooled, air-cooled, or evaporatively-cooled condensers;
  2. water-cooled heat recovery condensers;
  3. air-to-water heat pumps; and
  4. water-to-water heat pumps with a capacity greater or equal to 40 kW.

1.1.2 Water-cooled water-chilling absorption packages 

This Standard also applies to water-cooled water-chilling packages using lithium bromide refrigerant and including 

  1. water-cooled single-effect steam;
  2. water-cooled double-effect steam;
  3. hot water-operated water-chilling units;
  4. water-cooled, hot water-operated double-effect water-chilling units; and
  5. double-effect, direct-fired (natural gas, oil, LP gas) water-chilling/heating units.

1.2 Exclusions 

1.2.1 Vapour-compression water-chilling and heating packages 

The following products are not covered by this Standard: 

  1. water-to-water heat pumps with a capacity less than 40 kW;
  2. air-to-water units designed exclusively to heat potable water; and
  3. adiabatically cooled chiller products.

Notes: 

  1. Products that fall under Item a) are covered by CAN/CSA 13256-2.
  2. Products that fall under Item b) are covered by CSA C745.

1.2.2 Water-cooled absorption chilling packages 

This Standard does not include water-cooled absorption chilling packages that meet one of the following criteria: 

  1. absorption chiller/heater units with air-cooled condenser;
  2. applications employing heat pumping or exhaust gas firing; or
  3. absorption chillers not using lithium bromide.

1.3 Terminology 

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. 

Project need:

The C743-09 standard is now significantly out of date and does not align with the US AHRI 550/590 and AHRI 551/591 standard that has been updated several times since 2009 and therefore ratings generated per C743-09 do not align with industry ratings being supplied to NRCAN to prove compliance. The AHRI current standard is now AHRI 550/590 IP-2020 and AHRI 551/591 SI-2020 which were just updated again to revise test procedures and expand rating conditions as well as new product classification for heat pumps and heat reclaim. AHRI is also in the process of revising AHRI 560 IP and creating an AHRI 561 SI and because absorption chillers are included in C743 these also will be part of the update. In addition, the minimum efficiencies listed in the CSA standard are not aligned with the ASHRAE 90.1 2019 values which were revised in 2010 and 2015 in ASHRAE 90.1 table 6.8.1-3. Note that in the US chillers are not regulated by DOE but efficiency requirements are defined by ASHRAE 90.1 and then adopted by state building codes. In addition, AHRI has also added ratings requirements for heat pumps and heat reclaim chillers and ASHRAE 90.1-2019 added table 6.8.1-16 with minimum efficiency requirements for these products. There is also a new addendum X that revises Kadj and addendum Y that revises tables 6.8.1-16 which have been approved. Therefore, the standard needs to be updated for both the rating and test procedures as well as the efficiency requirements and new products. Products are now being shipping to Canada and it is important that this work be done as soon as possible. As AHRI 551/591 is a hard SI standard CSA should consider switch from IP converted ratings conditions to the hard-metric ratings defined in AHRI 551/591. Also, changes will be need to update AHRI 560 to a hard metric but this can be harmonized with a working group effort to update AHRI 560 and create an AHRI 561

Note: The information provided above was obtained by the Standards Council of Canada (SCC) and is provided as part of a centralized, transparent notification system for new standards development. The system allows SCC-accredited Standards Development Organizations (SDOs), and members of the public, to be informed of new work in Canadian standards development, and allows SCC-accredited SDOs to identify and resolve potential duplication of standards and effort.

Individual SDOs are responsible for the content and accuracy of the information presented here. The text is presented in the language in which it was provided to SCC.