Combined space and domestic water heating system

Changes are underway to the database that supports this list. As of March 14, 2025, the list has been frozen. Until the updated version is released, an interim version is available at the link below (.xlsx format).

Combined space and domestic water heating systems found in this database have been tested by a third party accredited by the Standards Council of Canada according to CSA P.9 — “Test Method for Determining the Performance of Combined Space and Water Heating Systems (Combos).”

The efficiency of a combined space and water heating system is measured by a value called the Thermal Performance Factor (TPF), which is the sum of annual thermal outputs delivered by the combo for space heating and water heating divided by the total thermal energy inputs needed to produce each component load. Choose a model that is properly sized for your application, with the highest TPF, as these systems are the most efficient.

Natural Resources Canada is not responsible for ensuring that the configuration of components of a system listed in this database is appropriate. Data provided is obtained from an external testing agency; contact the manufacturer for additional information and specifications.

Natural Resources Canada is not responsible for ensuring that the configuration of a system does not void the warranty of one or more of the components. Any questions regarding possible warranty concerns should be brought to the attention of the manufacturer of each component or the authority having jurisdiction.

Models:

Download all models (.xlsx format)

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