Buying a Water Heater

Buying a Water Heater

Many new water heaters are relatively inexpensive to purchase and install, but what about the ongoing operating costs? After all, you use hot water in the home every day - often lots of it! In fact, it can cost you seven times as much money to operate a water heater for 10 years as it did to purchase the system.

So it pays to be an informed consumer. Don't automatically accept the model proposed by your plumber or heating contractor - ask questions. Keep in mind that the unit that is cheapest to buy could end up costing you money in unnecessarily high energy costs for years to come. On the other hand, a high purchase price on its own doesn't guarantee long-term energy savings. It is the technology that is important.

The same advice applies if you are renting or leasing a water heater, which is a popular option in many parts of Canada. If a rented or leased machine wears out, ask your utility or energy supplier to replace it with an energy-efficient model.

Selecting an energy-efficient model that can reliably meet your needs will not only save you money, it will help the environment, because the less energy Canadians use, the fewer greenhouse gas emissions we produce. In making a decision, it's important to know that:

• there are several different types of water heaters
• for each fuel option, there are a number of different product types and models to choose from.
• size matters
• installation options can affect your choice
• a water heater's energy efficiency will have a big impact on its operating costs
• installation and service
  

Step 1 - Determine the capacity and size of tank your home needs:

• First, estimate your household's peak hot water demand, which usually occurs during showering. For example, 40 minutes of showering should be enough to shower at least three people, allow for hand- and face-washing at a sink, and still leave some hot water in the storage tank. Assuming you are using a low- flow showerhead, these hot water requirements can be met by a water heater with a first hour rating (FHR) of 270 litres (60 gallons). FHR is a measurement of how much hot water the heater can supply during a busy hour.

• Your next task is to determine the right tank size for your home's circumstances. Don't confuse tank size with your home's daily hot water consumption. Selecting a small water heater tank with a high FHR should result in good performance during the busiest time of the day while minimizing cycling and standby losses when hot water is not in high demand. The table below provides some guidelines on what size of tank you will need, based on typical recovery rates.
  

Depending on where you live, your fuel options may be limited - for example, perhaps natural gas is not available in your part of the country. Still, knowing the pros and cons of different fuels can help you make an informed decision. Options include:

• Electricity - Electric water heaters are easy to install, can be located in many areas of the home, and are available in various sizes and models. No venting is needed. On the downside, it takes a little longer to heat water using electricity than the other energy sources described here.
• Natural gas - These units produce hot water quickly, can be vented through a chimney or wall, and are available in various sizes and models. Some models are sealed combustion units, which means they do not require household air for combustion. Of course, the home must have access to natural gas. As well, the location of the heater in the home may be restricted by access to the gas line and chimney.
• Liquid propane - Liquid propane heaters are quite similar to natural gas heaters in both their performance and venting requirements. To use such a system, your home will need a liquid propane storage tank and regular fuel delivery.
• Heating oil - These heaters produce hot water faster than any of the others, which means that a smaller tank can be used. Some models can be sidewall-vented, and some are sealed combustion units that do not require household air for combustion. However, there are fewer models to choose from, and you'll need a heating oil storage tank and regular fuel delivery.
• Most Canadian households use the same energy source to heat water as they do to heat the home itself - but it's not a requirement. Any of these energy sources can be used to power your water heater, regardless of what fuel you use for space-heating, provided you have access to the energy and can meet any venting requirements.

Before you make a final decision, consult a heating professional or your local gas and electric utilities about your particular needs and circumstances.

Venting

Water heaters relying on gas, propane or oil as a fuel source require proper venting to safely remove combustion by-products during normal operation. There are two basic types of venting options:

• traditional venting method: combustion products from the water heater and space heater are naturally vented to the outdoors though a flue installed in a masonry chimney or a vertical vent. This venting system is used on a wide range of furnace and hot water combinations.
• direct venting or power venting: this type of venting can be accomplished either horizontally or vertically through an outside wall (sidewall venting). Direct vents rely on natural draft for venting, while power vents force the combustion products outside by a motor-driven fan. Typically, fan-assisted vents are used on higher efficiency water heaters where the products of combustion are not hot enough to provide adequate natural draft. You need to check the building codes in your municipality if there are any restrictions.

A qualified technician should give you advice on venting especially if you are converting.

Here are some conversions where venting are an important consideration in the purchase and installation costs:

• converting to a gas or oil-fired water heater in an electrically heated home. In this case, since no chimney will be available, you have the option of installing a direct vent or power vented gas or oil water heater. These technologies vent the flue gases through a sidewall of the home.
• converting from an oil-fired water heater to a propane or gas model. The home's existing chimney or vent may need to be resized and the liner changed to maintain adequate draft and avoid condensation in the vent. Alternatively, you can install a direct vent or power vented unit.
• replacing an existing gas, propane or oil-fired water heater with a more efficient model. Sidewall venting may be the only practical option because of the increased potential for condensation to form in the vent system.

Of course, you also have the option of installing an electric water heater in any home, since no air supply is required and the fuel source (electricity) is already being used in the home.

Once you've determined the capacity and size of water heater you need and selected an energy source, check the energy factor (EF) of different models to identify the most efficient heater that meets your needs.

Select a water heater with the highest EF. This information is found in the manufacturer's product specifications brochure or on the manufacturer's Web site. The EF measures the efficiency of the water heater by comparing the energy supplied in heated water to the total daily energy consumption of the water heater. The EF is determined by the manufacturer and is based on a standardized test procedure. Under Canada's Energy Efficiency Regulations water heaters sold in Canada must achieve a minimum EF, which is based on the size of the storage tank. You will probably find that the larger the storage tank, the lower the EF, especially in sizes above 65 gallons.

The range in efficiency ratings within a certain tank size is accomplished through a variety of design features and quality of manufacture. In many cases, the higher efficiency units are usually more expensive, and perhaps carry a longer warranty protection.

The bottom line is, the lower the EF, the higher the operating costs.

This is the final step in the process - and often it's the easiest. The simplest way to purchase a water heater is directly from a utility: installation and service are included, and the entire transaction can be financed through monthly payments. If your utility doesn't sell water heaters, you can purchase a system from a contractor or through a retail outlet. Look for a supplier who promotes the quality of the product and good service as opposed to just low prices.

Source: Natural Resources Canada (NRCan) - Office of Energy Efficiency