How hot is your water? Get it right for safety and savings

hot water temperature adjustment

Everyone likes a hot shower now and then, but at Mary Francis' Victoria home, turning on the taps was downright dangerous. When her husband nearly scalded himself, Mary knew something had to be done.

"I called my handyman and he said the temperature was turned right up," she says on the phone. The hot water tank was installed "something like 10 years ago" she adds, relieved that nobody had been injured in all that time.

Parents who remember their curious young children turning the knob on the hot water tap during a bath can sympathize.

Mary, a member of Team Power Smart, sent an email to BC Hydro relating what happened. Not only did her email get a reply from a BC Hydro engineer with a suggestion on what the problem might be, but it also provided an opportunity for us to tell her story.

For safety, keep temperature at faucets a maximum of 49 °C

The current BC Plumbing Code requires that electric storage-type service water heaters to be set at 60°C. This doesn't apply to other types of water heaters that use different fuel such as gas.

However for safety, downstream of the heater, at the tub faucet or shower head, the water outlet temperature should not exceed 49 °C. This lower temperature can be achieved by installing a pressure balanced or thermostatic mixing valve before the fixture outlet.

Limiting the faucet or shower head temperatures to 49°C reduces the likelihood of someone being injured.

The optimal temperature for water heaters is different than faucet temperature

The BC Plumbing Code calls for an electric service water heater temperature of 60°C, because storing hot water below this temperature may lead to the growth of legionella bacteria, which poses a health risk (not a concern for gas-type water heaters). But again, it's vital to use a thermometer to check that temperatures at all faucets don't exceed 49°C.

Faucet temperatures can be adjusted at fixture outlets, via individual pressure-balanced or thermostatic-mixing valves often located under sinks.  

It's a simple matter to check the temperature of your hot water using thermometers you can find at your local hardware store. You can use a strap-on thermometer on the pipe itself by running hot water in the bathtub for a few minutes.

Or you can use a water probe thermometer at the tap itself, by holding the probe under the hot running water. The added benefit is that you can check the temperature at every tap in the house.

To install a mixing valve for the sink faucet, tub faucet or showerhead, look online for explicit instructions on how to do this, or hire a plumber or other contractor to make the adjustments.

How hard is your water?

Residents of different areas of British Columbia need to watch for different things. In the interior and northern areas of the province, for example, there is high mineral content in the water. That leads to sediment in the tank and calcification on the heating elements.

Team Power Smart member Robert Tisdale has seen how bad it can get. The 74-year-old Abbotsford resident used to service hot water heaters in Ontario.

He says that one tank he opened was filled up with more sand than water. That's just wasting electricity, he says, because the energy is wasted heating the grains of sand, not the molecules of water.

People who live in an area with hard water should check their hot water tank every two to three year and drain it every five or six years to make sure it's okay.

That was also the advice Mary received. "My handyman is coming next week to clean out the sediment," she says.

Regular maintenance key to a well-functioning water heater

At the end of the day it's all about maintenance. If you know what you've got, you'll know what you need to do.

Know what you have heating your water. Is it electric or gas? How old is it? And where do you live?

Understanding these things will tell you a lot about what you have to deal with.

And while it's possible to perform some basic maintenance yourself, hiring electricians and plumbers to do the work of replacing parts, or dealing with tank sediment or mineral build up is always a good approach. They will be able to do the work faster, and safer.