"Understanding Your Home" by Building Inspector Mark Visser
Home Page
About Us
Fireplace/Wood Stove
Heating and Cooling
Windows and Doors

Gas-fired water heater

Power vent



Temperature control
The main reasons for tank liner damage are overheating and hard water. If super hot water is needed, be sure to reset the dial to normal when done

Water Heaters

Need more information? Use our search box

Water heaters and tankless water heaters are commonly powered by natural gas, oil or electricity. A water heater is, after the furnace, the largest energy consumer in your home. Therefore it is important that the water heater is serviced annually which is possible only if the tank is owned by you. In my neck of the woods rental hot water tanks are NOT serviced and could be wasting a lot of energy. Water heaters typically have a capacity of between 30 to 40 gallons. Electric water heaters often have a larger capacity due to their slower recovery rate.

Most electric water heaters have two heating elements, one top and one bottom. Reset buttons and adjustable temperature are located behind the cover plates.
A gas fired water heater is the most common and with proper maintenance will last a long time.

Power vented water heaters
use a fan to assist venting of combustion gases. They do not need a chimney and are vented to the outside. They can be placed anywhere in the basement. The power vent needs electricity which means that if the power is out for a long time you will have no hot water.
Electric water heaters
are easy to install, can be located in many areas of the home, and are available in various sizes and models. They need no venting. The heat recovery rate is longer than in gas or oil fired water heaters so electric water heaters are larger in in size and capacity than their counterparts.
Water heater maintenance
. Burners should be cleaned and adjusted annually to conserve energy. Any water heater tank will lose efficiency if sediment accumulates in the bottom so, sediments should be flushed out on a regular base. In electric water heaters, sediment can cover the lower heating element, which can overheat and burn out resulting in an up to 50% lower recovery rate.
Distribution water pipes
should be insulated to reduce "stand-by" heat loss, especially insulating the first six feet from the hot water tank where the heat loss is the greatest. I prefer the wrap-around, foil backed fibre glass insulation over the standard foam insulation which requires a lot of precise cutting and taping around floor joists, pipe elbows and tee's.

Pressure relief valve

Tankless water heater system
25"(H) x 15" (W) x 11"(D)

Tankless water heaters may be fairly new for us but they have been used for more than 50 years in Europe. The principal of tankless water heating systems makes common sense as they are very efficient and economical to operate. Water is only heated when hot water is called for. However, the systems are expensive to purchase and expensive to install.
Pressure relief valve (PRV)
. The PRV is a safety device that will relieve the tank pressure if the thermostat fails. It is usually located near the top of the water heater. The discharge pipe from the PRV should be piped to within 6" (150 mm) of the floor.

Back to Top