Minnesota Water Heater Service Repair & Installation MN

Water Heater Repair Service MN | Water Heater Plumber Minnesota

Most consumers take for granted their hot water supply and rarely think about their water heaters once they have been installed. Where water heaters are concerned, “out of sight” is usually “out of mind,” and many people don’t realize that they have a potential bomb inside their home. When safety devices on a water heater fail, bad things can happen! And to date, many are unaware of the need to have their water heaters regularly maintained to prevent water heater explosions.

Hot Water Heater Safety

Most of the time your water heater just sits there quietly doing its job. But unlike your family dog, it isn’t likely going to go to the door and bark and scratch. It could just suddenly blow up.

What?  You didn’t know your water heater could be so lethal?  It can be if it has not been installed properly, if hazards have developed over time, or if it has been tampered with.

Temperature and Pressure Relief Valves

The Temperature and pressure relief valve (T & P) is the primary “back-up” safety measure which prevents the water in the pressurized hot water cylinder from overheating. An explosion of a water heater presumes at least two system failures. Generally, the safety mechanism in the controls, coupled with a properly installed and working T & P relief valve, insures a safe system.

To insure their safe operation, water heaters must be installed with temperature and pressure relief valves. A T&P relief valve is a two-in-one safety device, which, as its name implies, responds both to excessive temperature and to excessive pressure in a water heater.

A T&P valve responds to excessive temperature by expansion of the thermostat which lifts the disc off its seat and discharges overheated water, allowing cooler water to enter the tank and replace the discharged hot water in order to moderate the water temperature. When a valve is relieving water in volume, it is generally due to excessive temperature.

The valve also responds to excessive pressure by discharging water to prevent further pressure increase. If a T&P valve is dripping, rather than relieving in volume, it usually indicates either thermal expansion or debris on the seat, which prevents the valve from closing tightly.

Thermal expansion is an increase in system pressure over that regulated by the reducing valve, check valve or backflow preventer. When water is heated in a closed system, it expands and causes an increase in pressure. When the system is opened, pressure will return to normal, and the relief valve should stop dripping. When a backflow prevention device or check valve is installed on the water service entering a building, a closed system is created. When water is heated, it expands. Because the water has nowhere to go in a closed system, a potentially dangerous situation is created.

Prevent Water Heater Explosions

For over a decade it has been known that an inoperative or improperly installed temperature and pressure (T & P) relief valve on a water heater can turn an ordinary water heater into a potentially explosive and life-threatening “bomb.”

http://waterheatersafety.com/files/Watts_Danger_lurks_Video.wmv

A safety valve such as a T&P relief valve is a mechanical device which, like any mechanical device, is subject to failure, particularly when tampered with or improperly installed. If the valve cannot do its job, the water in the tank may become superheated (over 212°Fd, causing a thirty gallon water heater to explode with the equivalent force of one pound of dynamite. This is not theory or conjecture. It is a matter of record that such explosions occur, and have occurred, at the expense of human life. Yet, only a few are aware of the need to have their water heaters regularly maintained to prevent water heater explosions.

The T&P relief valve itself is not the cause of such explosions. Rather, it is the misapplication or malfunction of the valve, which sets the stage for disaster.

What follows is an extract from the fire journal report on an incident that took place at the Star elementary school in 1982. Six children and one teacher were killed when a hot water heater exploded in the Star Elementary School cafeteria in Oklahoma City. Regulations were later enacted there requiring annual inspection of domestic hot water heaters in all public facilities.

Hot water heater in school kills seven

Location: Spencer, Oklahoma
Facility: Star Elementary School

http://waterheatersafety.com/files/Spencer_Oklahoma_Hot_water_heater_in_school_kills_seven.pdf

And one more thing: T&P drain lines should go down and out. Never up. If the valve opens, water will pool there and corrode it shut. Or freeze in the line in colder climates. There SHOULD be a drain line, usually to within about six inches of the floor, or plumbed outside. That’s code and it’s to prevent you from being scalded if the valve should open while you’re standing next to it.

Finally, if water is running out of your T&P line, look for the cause. It might just be a bad T&P.  But it could also signal high-pressure problems or a dangerously defective control. Don’t ignore it!

Clearly, the Temperature/Pressure Relief (TPR) Valve serves an extremely important function, so to ensure the safe and proper operation of a water heater, it should be corrected immediately by a qualified and licensed Minnesota plumbing contractor.

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