How is a water heater sized?

A storage tank is matched by first-hour rating to your busiest hour: the stored volume plus what the burner or elements reheat during that hour. Nominal tank volume, floor area and bedroom count are not sizing figures.

Why does the tool give a range instead of one model?

Demand depends on how the household actually uses hot water, so the tool returns a defensible range and the published models that meet it; the assessment confirms the exact figure from fixtures and simultaneous use.

What about tankless water heaters?

Tankless units store nothing, so they are sized by flow at the winter temperature rise, not by first-hour delivery. Metro Vancouver's winter rise is roughly 40 °C, and the tankless sizing guide explains the arithmetic.

Is the tool result an offer?

No. It is a planning figure from published model ratings. Final equipment selection follows CANRO's assessment, and estimates for replacements and installations are free.

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Size my water heater

Storage tanks are sized by first-hour delivery against the busiest hour, never by house size. Answer three questions and see the published models that fit your demand.

First-hour target: 230–280 L (61–74 US gal)

For three or four people, size by the first-hour rating against the busiest hour. Most households sit inside this range; the assessment confirms the exact figure.

Loading the published models…

Want the number confirmed? CANRO sizes from measured demand, checks the venting, gas supply and space, and gives a free written estimate for replacements and installations.

604-359-1081 Request a sizing assessment Ballpark estimate

What this does not tell you

A first-hour figure does not confirm the venting, gas supply, electrical circuit, space or water quality at your house. Those decide which of the matching models can actually be installed, and are checked at the assessment.

The winter rule for tankless

If you are comparing tankless units, remember they are sized by flow at about a 40 °C rise in Metro Vancouver's winter, not by first-hour delivery. The guide below walks through the flow arithmetic.

Confirm the size on site

CANRO counts fixtures and simultaneous use, checks the flue or vent route, gas and electrical supply, and quotes in writing. Replacement and installation estimates are free.

604-359-1081 Book an assessment

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