Water heater thermostat setting for a Calgary family, how hot?

We do not publish a tank setting of our own: the water heater's manual gives the manufacturer's setting, and a plumber can set it for your household. The one Calgary figure we can give you is at the tap: at the final inspection for bathroom work, the City of Calgary checks that tub and shower water does not exceed 49°C.

Why the tap temperature matters

Hot water at the tap can scald, especially children and older adults. Where the tank has to run hotter than you want at the tap, a plumber can fit a tempering or mixing valve that blends in cold water so the delivered temperature stays lower.

Calgary's hard water adds a wrinkle. The City of Calgary reports hardness ranging from roughly 141 to 274 mg/L depending on which treatment plant serves your neighbourhood. Scale can settle at the bottom of a tank, which is why flushing it and having the anode rod checked are worth doing.

On a tankless unit, regular descaling of the heat exchanger matters for the same reason.

On the permit side, a straight thermostat adjustment needs no permit. If a plumber recommends adding a tempering valve where none exists, that is a change to the plumbing system and a City of Calgary plumbing permit would apply. The City issues homeowner plumbing permits to owners who live in the home and do the work themselves; a contractor takes out their own permit for work they perform.

Gas work is separate. Adjusting a gas water heater's thermostat dial is not gas work, but any change to the gas line, venting or the heater type requires a gas permit, and in Calgary that permit is for a certified gasfitter.

For a service call to set the temperature, flush the tank and inspect the anode rod, expect to pay a call-out fee in the range of $50 to $150 plus the plumber's hourly rate, typically $85 to $150 during regular hours in Calgary. Adding a tempering valve is a separate quoted item.

When you have two written quotes side by side, line up the tempering valve model and labour, the flushing and anode rod inspection, whether the permit is included if a valve is being added, and the warranty terms on both parts and labour.