ANSI Z21.10.3-2017/CSA 4.3-2017 - Gas-fired water heaters, volume III, storage water heaters with input ratings above 75,000 Btu per hour, circulating and instantaneous
CSA/ANSI Z21.10.3-19/CSA 4.3-2019 - Gas-fired water heaters, volume III, storage water heaters with input ratings above 75,000 Btu per hour, circulating and instantaneous