How to choose and where to mount the check valves

In everyday life and when laying branched plumbing and industrial communications, a variety of standard sizes of return valves are used. The duration and complexity of installation work depends on the correct choice of their type.

Types of reverse valves

The standard sizes of this technique are distinguished by:

• The method of connection to the pipeline. Produce check valves of coupling and flange types. In the first case, there is a thread on the mounting part of the gate, in the second – a flat flange with bolt holes.
• Materials of details. Steel, cast iron, and copper alloys (brass or bronze) are used.
• Designs of moving parts – with a sliding valve or a parallel spool.
• The nominal diameter of the pipeline. For standard types of check valves, their dimensions are set in accordance with GOST 5762-2002 standards.

Premises of the house in which the installation of shut-off valves is required

Taking into account the peculiarities of operation of this type of pipe fittings, they are installed:

• In the kitchens. Standard installation locations are under the sink or at the bottom of the sink, on pipes going to the faucet.If there is a dishwasher, the second valve is placed on an additional pipe coming from the hot water source.
• In the bathroom. The valve is mounted directly under the tank. Depending on the location of the tub and sink, there may be one or two additional shut-off valves.The water shut-off valve of the sink is usually located under it or against the wall. If there is a lack of space, the reverse shutter can be located in the basement.
• The water heater has a reverse gate located above the device.
• In the laundry room - the reverse shutter is installed above or behind the washing machine.

The main shut-off valve for water turns off its supply to the whole house and is usually located in the basement or on the outer wall in the service area of the building.This main valve is designed to prevent accidents of the water supply, or in case of an operational shutdown of the water supply for repair work.

Factors to be taken into account when installing check valves

In most cases, the limiting circumstances are:

• Temperature fluctuations. Thermal jamming occurs when the valve is tightly closed and the supply of heated water continues. Later, when disconnecting, thermal compression of the saddles occurs, as a result of which the wedge does not fit tightly into the saddle. In such cases, reverse valves with parallel seats are used;
• Pressure drops. Sometimes in high temperature applications, the working medium jams the stem in the lid area when the valve is closed. In this case, a water hammer occurs that can destroy a section of the pipeline. You can prevent such a nuisance if you install check valves made of materials with low thermal conductivity.

Brass or bronze valves also help to restore the operability of the valve when the previous values of temperature and/or pressure are stabilized.