Electric water heaters: criteria for choosing

Is it time to replace your water heater?

The lifespan of a water heater is 10 to 15 years. Locate the date of manufacture on the descriptive plate on the tank. Otherwise, watch for these warning signs that your water heater may be at the end of its life:

• The water doesn’t feel as hot as it used to.

• It runs out faster when you shower (probably due to a burned out heating element).

• The water has a slightly reddish colour.

• You notice rust at the bottom of the tank or drops of moisture on the sides of the water heater.

If you see signs like these, your tank probably needs to be changed.

How to choose the water heater capacity

Take a moment to assess your situation and, above all, your hot water needs, which may have changed since your last purchase. A water heater that’s too big (60 gallons) will jack up your energy bill, while one that’s too small (40 gallons) will deprive you of hot water just when you need it.

To figure out which one is right for you, consider the number of occupants, the number of bathrooms (and faucets), and your water needs. Are you a bath person? Do your teens like taking long showers? Do you use the washer and dishwasher often, and sometimes even at the same time? If your water consumption is high, you need a 60-gallon heater.

Key components of a hot water tank

First of all, you should know that your electric water heater must meet the requirements of the Canadian Standards Association (CSA) C-191 standard, which requires, among other things, a double wall filled with 2-inch-thick foam insulation.

Water inlet

A good quality water heater will have a water inlet at the base of the tank. This prevents cold water from coming into direct contact with hot water accumulated at the top of the tank, ensuring better water circulation and optimized heating (mainly to prevent the spread of Legionella). You’ll get 10% more hot water than with a standard model.

Heating element

Some water heater models come with three heating elements of different wattages instead of two. The advantage is that they maintain a more uniform temperature inside the tank and therefore use fewer watts, which is a big plus during peak periods. This is the case of the ECOPEAK water heater, developed by Giant with the support of Hydro-Québec.

Inside the tank

The quality of the inner tank lining can affect its longevity. A double glazing process with double firing provides increased corrosion resistance and extends the life of the water heater to up to 15 years.

The magnesium anode

The rod attached to the top of the hot water tank, protects it from corrosion. It dissolves slowly when the water is soft but quickly when the water is hard. If your water is hard, a standard anode should be replaced with a more passive aluminum anode.

Warranty

The manufacturer’s warranty is a good sign of the quality of a water heater. Entry-level models generally offer a 6-year warranty on the tank (leaks and parts), while high-end models offer a warranty of 10 years or more.

Good to know

Your water heater should always be kept upright during transportation to prevent breakage. The manufacturer may revoke its warranty in case of improper transportation or installation. The same applies if your water is hard (high in limestone) or comes from a well. Under the effect of heat, limestone may agglomerate and form scale. In the long term, scale clogs your pipes and water heater.

Not sure about your decision? Have questions? CAA-Quebec’s Residential Advisory Services can help you make the choices that are right for you.

How to measure the energy efficiency of a water heater

To determine if your water heater’s energy consumption is normal, consider the following:

• Heat loss, i.e., the loss of heat in unused water through the tank walls, the insulation on which may vary. This loss varies according to the temperature of the hot water and of the ambient air: the colder the room where the heater is located, the greater the loss.

  For example, a 40-gallon (180-litre) water heater can lose the equivalent of 50 to 70 watts per hour. The bigger the tank, the more heat that escapes. A 60-gallon (270-litre) model can lose 75 to 95 watts.

• The first hour rating also helps assess a heater’s efficiency. This rating measures the amount of water the heater can produce in an hour when water consumption is high. It’s listed on the technical data sheets for most models.

  A 60-gallon (270-litre) tank with 4,500 watts of heating power will produce 259 litres of hot water during the first hour. A 40-gallon (180-litre) tank with 3,000 watts of heating power will provide 173 litres of hot water. On average, it takes 50 to 70 litres of hot water for a bath and 40 to 60 litres for a shower.

Should you rent or buy your water heater?

The price of a water heater varies according to its capacity and interior components. Rental will certainly cost more, but it has some advantages, such as cost distribution (monthly payments and no down payment), zero repair costs in case of problems, and replacement of the water heater at the end of its life. It’s also a great option if, for example, your water heater needs to be changed but you’re thinking of moving in the next few years. Still not sure? Compare both options: renting or buying.

Water heaters and home insurance

Insurers generally recommend replacing your water heater after 10 to 15 years of service life. Beyond this period, which varies from one insurer to another, the insurer reserves the right not to cover damage caused by water heater failure. You may also be denied compensation for damage if the heater was improperly installed. Make sure you ask.