When replacing your Hot Water Tank make sure that it is properly installed by a professional who understands the importance of the "temperature/pressure release valve" TPRV and the "discharge pipe" as well as their functions.
It is extremely important that your hot water tank has a properly installed and functioning temperature/pressure release valve and discharge pipe. The TPRV will either be on the top of the tank or on the side near the top. The TPRV is designed to release any excessive build-up of pressure or temperature from the tank. This valve must not be capped off or plugged in any way! If it is, there is no way for pressure to be released. Also check for any signs of leakage or corrosion.
The discharge pipe is a pipe attached to the valve that - in case of pressure - will direct the steam downwards towards the floor, into a bucket. Occasionally hot water tanks are located near areas that have regular traffic such as laundry areas. The purpose for directing the scalding steam downwards is to avoid a situation where the escaping steam could burn an individual who happened to be standing near the tank at that time. So it is critical to ensure that the TPRV with a proper downspout is in place.
If the heating element and/or thermostat were to malfunction, the temperature of the water inside the tank could increase to the point where it is producing steam. If the situation progresses, and there is no outlet for the steam, the increased pressure could cause the hot water tank to explode. The purpose of the temperature/pressure release valve and the discharge pipe is to prevent this from happening. Without the ability to release pressure, your tank could essentially become a ticking bomb. Awareness and prevention are essential to a safe home; check your hot water tank!
If you are unsure, or have any questions, do not hesitate to contact your local Canadian Residential inspector!
Discovery Channel’s popular show "Mythbusters" video taped the possible consequences when a hot water tank malfunctions. Please watch the clip below.