Tankless Water Heaters near you

Natural Resources Canada describes a tankless water heater as a unit that heats water only when it is needed, as it flows through, with either a gas burner or an electric element. A flow sensor detects that a hot tap has opened and signals the burner or the elements to start; the unit then adjusts its output to reach the set temperature and stops as soon as the flow does.

Natural gas and propane models are often chosen to serve a whole house, since a burner can deliver a great deal of heat from a small cabinet. Electric models are easier to place because they need no venting, but heating cold water instantly with electricity takes a lot of current, so a whole-house electric unit can require several heavy circuits and sometimes a larger service. Smaller electric units are often installed at a single sink or a distant bathroom, as point-of-use heaters.

A combination, or combi, unit is a gas appliance that heats both the household's water and the house, usually through radiators or in-floor heating; because its sizing has to balance both loads, it calls for a contractor experienced in hydronic heating as well as plumbing.

A tankless unit is sized by flow and temperature rise, not by volume. The plumber needs to know how much hot water your household draws at once at its busiest moment, and how many degrees the unit has to add to the incoming water to deliver it. Every model has a maximum heating capacity: the colder the water coming in, the more of that capacity goes into warming it, and the less flow the heater can supply at the temperature you want.

That is why winter matters so much here. Water from a municipal main or a private well is at its coldest in the depths of winter, and a unit that easily runs two showers in September may manage only one in February. A careful installer sizes for the coldest incoming water you can expect where you live, lists the fixtures that realistically run together, such as two showers and the dishwasher, and checks the flow of your showerheads. NRCan advises consulting an experienced plumber to estimate your home's hot water demand before you buy.

While it runs, a gas tankless burner uses much more gas than a typical tank burner, so the gas piping, and sometimes the meter, may have to be enlarged. Most models vent through a side wall or the roof with a sealed intake and exhaust. Condensing units cool their exhaust until it condenses, so they can vent through plastic pipe but produce acidic condensate that must be piped to a drain, often through a neutralizer. The outdoor terminals must stay clear of snowbanks and ice, and Health Canada recommends a working carbon monoxide alarm in homes with fuel-burning appliances.

A whole-house electric unit shifts the load to the panel: the electrician checks whether the service can carry it on top of heating and other large loads and runs the dedicated circuits, and if a service upgrade is needed, that can tip the choice toward gas or another type of heater.

Who does the work is regulated. In Quebec, gas work must be carried out by a specialized contractor who is a CMMTQ member, even in an owner-occupied house, and plumbing contractors need a licence from the Régie du bâtiment du Québec. In Ontario, only fuels contractors registered with the TSSA may install a gas appliance. In British Columbia, Technical Safety BC requires a permit to install or replace a gas water heater, gas piping or a vent system; a licensed contractor you hire applies for it on your behalf, and at least one inspection must be requested within 180 days of the permit being issued.

Hard water, common where homes are supplied by a well or by groundwater, carries dissolved minerals that come out of solution when it is heated and cling to the hottest surfaces; in a tankless unit, those are the narrow passages of the heat exchanger. Scale acts like insulation, so the unit works harder, its hot water output drops, and it may eventually shut itself down with an error code to protect the exchanger.

Descaling is a job for a technician: they isolate the heater with its service valves, circulate a descaling solution through the heat exchanger, flush it and clean the screen at the water inlet. How often depends on your water's hardness and how much hot water you use, so follow the manufacturer's schedule; NRCan recommends having a water heater serviced every year or two by a qualified professional. Where the water is very hard, the plumber may suggest a softener or a scale-reduction device upstream of the heater.

According to Natural Resources Canada, an ENERGY STAR certified tankless water heater uses 30% less energy, on average, than a storage tank type. Tankless models are rated with an energy factor: the higher the number, the more efficient the heater. When you compare quotes, compare certified models with one another, and keep in mind that actual savings also depend on energy prices and on the way your household uses hot water.

Condensing gas models recover heat that would otherwise escape through the vent, which generally places them among the more efficient choices. Rebates for efficient water heating vary by province, utility and municipality and change often, so check what is open where you live, and its conditions, before you buy.