Hot Water Heater Safety

Jump in the shower and aaah! Hot water. Boy does it feel good. But where does it come from? What type of hot water heater do you have? And have you checked to make sure it is installed and operating safely? Well, this article is designed to give you a few things to look for to ensure the safety of your hot water heater. While on demand and indirect fired units are becoming more and more commonplace, most homes still utilize the good old free standing electric, oil, or gas fired units. They generally range from 40-80 gallon capacities. This article will concentrate on these units.

There are four primary things to look for regarding the safe operation of your hot water heater. They are: wiring, venting, pressure relief valve, and water temperature. Let's explore!

1) The wiring- often times we find that the wiring of the hot water tank is over fused at the electrical panel box. The breaker protecting the wiring must correspond in size to the wire feeding the hot water heater. Ex. If a 12/3 wire is used the breaker should be no larger than a 20 amp. If the breaker is a 30-40 amp, this is called over fusing. Over fusing the electrical wire is a serious fire hazard and should be corrected. Have an electrician review and repair accordingly.

2) The pressure relief valve should have a pipe extension installed on it. This extension should run down along the unit to appx. 4-6" from the floor. This is necessary to protect a person from scalding should the valve active. Review your water heater and repair as needed.

3) All oil and gas fired hot water heaters are vented. The combustion gases which include carbon monoxide must be vented to the outside. This can be done via direct venting or venting into a flue with a connector pipe. In either case, look for the following and repair as needed.

Disconnected connector piping allowing gases to escape into the structure.
Corroded piping requiring replacement.
Any obstructions in the connector pipe or flue.
Ensure the unit has a proper vent hood on top of the unit.

4) Lets talk temperature. Ideally and it's a matter of opinion, Hancock Home Inspections recommends an operating temperature of 115F to 120F. A temperature that is too hot creates a burn hazard. Below are the exposure times and temps for a third degree burn.

At 120F in takes 5 minutes for a third degree burn
At 130F it takes 30 seconds for a third degree burn.
At 140F it takes 5 seconds for a third degree burn.
At 150F it takes 1.5 seconds for a third degree burn.

Note: Domestic Hot Water that is received from a domestic coil of a boiler unit can easily exceed 160F before the tempering process occurs. A mixing valve should be used in order to quickly temper the hot water to a safe temperature.

We hope you find this information helpful.