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steam boiler pressure relief valve

Overheating of the coolant leads to its strong expansion, especially if the temperature has reached boiling point. When the heat carrier expands, the pressure in the system rises, which can lead to serious consequences: from a slight leak of connections or failure of components of the heating system, to the rupture of highways in inaccessible places (walls or under the screed floor).

A well-known way to prevent the destruction of the heating system due to high pressure is a safety folding valve. In the article, we will examine in detail its device and the principle of work, determine the criteria for the choice of mechanism, the algorithm of installation in the heating system, as well as actions in the situation if the pressure valve leaks.

The increase in the temperature of the coolant in the water circuit of the heating leads to an increase in the pressure exerted on the walls of the system. Particularly critical are temperatures above 90-95 degrees Celsius, when water begins to boil, releasing steam. The pressure in the system increases exponentially. If modern pipes and radiators are calculated, as a rule, on pressure 6-9 bar or more, the most vulnerable point of the system are heat exchangers boilers, which in modern models withstand pressure up to 3 bar, and at the older and even – 2 bar.

Subsequently, there may be not just a leak of the heat exchanger, but also a short circuit, a serious deluge due to the leaking of large volumes of heat carrier.

The safety valve provides automatic release of steam or heat carrier, freeing up space in the system for expansion due to heating, which prevents the pressure inside the water circuit from reaching critical values. After the pressure is relieved, the valve also automatically closes. The valve crashes into the pipe near the boiler itself, often with it also install a gauge and automatic blower, together this complex is called a safety group.

If modern models of gas and electric boilers thanks to advanced automation are able to prevent overheating, at least just turning off the burners in a timely manner, then for solid-fuel boilers the installation of a safety valve is mandatory. Even after the flap is closed, the heat exchanger in the solid-fuel boiler continues to receive heat for some time. It is because of the inertia of the heat generator can occur serious overheating.

Also mandatory reset valve is for steam boilers (usually used for industrial purposes). However, we recommend inserting a safety valve into the heating system with any boiler, including gas, installing a valve as part of a safety group.