The safety valve for boiler (water heater): the structure, installation

Self-installation of the boiler is considered responsible activities requiring maximum compliance and connectivity rules. The water heater strapping necessarily involved a security group, which includes a safety valve for the boiler - a small but functionally important device.

In this article we consider the varieties of safety valve, its design features. After all, to make installation of the heater with no errors, you should understand the device and the principle of operation of the valve.

Also provides instructions for the boiler and piping installation tips safety valve, will give useful advice on choosing the right equipment.

The content of the article:

  • Types of safety valves
  • Design and operation principle
    • Apparatus safety valve
    • The operating principle of devices
    • Why not sufficiently check valve assembly?
  • Tips for choosing a valve model
  • Installation instructions for the boiler piping
  • Professional installation recommendations
  • Conclusions and useful videos on the topic

Types of safety valves

Safety valves are often confused with the reverse, and sometimes simply use the term "inverse" in relation thereto. In fact, these are two completely different devices, although having common features.

The check valve is responsible for the motion of the medium inside the pipeline in one direction only, while the designation safety - to protect the tube and units connected thereto from damage provoked by the network pressure increases above normative.

Changing concepts occurs because the second fuse important function is to provide a barrier to fluid movement in the opposite direction.

The spring safety valve

industrial type mechanisms differ from the more simple and compact devices used in everyday life. It looks like a spring valve installed at the production conduit

There are several types of locking mechanisms to protect sophisticated technical equipment from pressure surges. Among them spring, magnetic spring, lever, lever-freight unit.

Selection of a particular type is explained purpose and characteristics of the medium pipe, which moves thereon: water, oil, hot steam, aggressive chemical solutions.

For mounting the electric boiler is one type of valves - spring. They may differ in appearance, but their internal content looks the same.

Design and operation principle

To start disassemble detail structure and operation of the safety valve.

Apparatus safety valve

The safety valve, like the other types of reinforcement, characterized by a simple structure and is a combination of two spring mechanisms concluded generally metal casing.

The fundamental difference between the brass and steel products not, but brass is a little more expensive and, in the opinion, longer. A spring within the housing made of chrome-plated steel.

Driving safety valve device

A circuit which is well visible on the inner valve contents. The tube portion cuts, preventing backflow of water, and the safety module is located perpendicularly to the movable spout

The operating principle of devices

Both cylinders arranged perpendicular to, have a similar structure, but different purposes. The part located on the water course, within the spring-loaded and has a "bowl" with a sealing ring.

The spring holds the mechanism closed and prevents fluid back into the pipeline. The end of the cylinder equipped with threaded "male-female" tapping into the system and connect to the cold-water boiler fitting.

Inside the second cylinder is set more powerful spring which is in the neutral state even with a small increase pressure indicator.

If the line is a sharp increase in pressure above normal, the spring is activated and opens the liquid-ejecting port. The outer end of the cylinder is covered by a plug, a screw or a lever device.

The elements of the safety valve

Appearance of the safety valve with a plastic lever 2 - thread for cutting into HVS network 3 - thread for connection to the boiler, 8 - mini-pipe for withdrawal of liquid 9 - lever to force opening

Yellow marker in the picture circled area on which emboss marking. It indicates the limit nominal pressure at which the valve operates. The pressure stated in MPa, but it is easily converted to the atmosphere: 0.7 MPa atm = 7.

Also, the housing has an arrow indicating the direction in which water moves from the cold-water tank to the heating system.

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Mounted pressure relief valve with a pipe

To discharge pipe for the liquid is attached a thin plastic tube, the second end of which is output to the drains - so as not to leak

The housing of the safety valve from a metal

The body is made in the form of the letter "T" and has four holes, two threaded connection, one for control and the smallest spring - for water discharge

Metal spring with a sealant

Spring with a "tray" and the sealing ring is installed in a cylinder embedded in the conduit. It operates in the reverse movement of water and creates a barrier

Small "shear" outlet for water

The main purpose of the holes - excess fluid discharge in order to reduce the pressure on the network. However, it can be used to force the water drain

Mounted pressure relief valve with a pipe

Mounted pressure relief valve with a pipe

The housing of the safety valve from a metal

The housing of the safety valve from a metal

Metal spring with a sealant

Metal spring with a sealant

Small "shear" outlet for water

Small "shear" outlet for water

Although through the hole in the valve to drain the water is convenient, experts recommend not to use manual controls too often.

Forced to use the lever for opening the valve must be as little as possible, and to prevent or repair drain the water It can be in another way, for example, loosening the water supply nozzles.

Why not sufficiently check valve assembly?

The safety device is a component element, so look in the shops and pick up parts for the installation of a new water heater is not necessary. But when moving the item may be lost.

Perhaps that is why some craftsmen, setting b / a boiler instead of the standard safety model crashed check valveThat is strictly forbidden instruction.

Improper piping with a check valve

This harness is wrong. To drain water is made horizontal outlet with shutoff valve, and below this node is connected a check valve without a safety mechanism

Anyone who begins to operate the boiler with incorrect strapping, runs the risk of not only equipment, but also the lives of people. Balanced thermodynamic heating action in the water can get out of control, and then the usual boiler converted to present an explosive device.

Pressure increased to 5-6 atmospheres, increases the water temperature inside the tub to the critical boiling point, then even higher. It accumulated a huge amount of steam and the explosion occurs.

Explosion due to incorrect boiler piping

Consequences of explosion of domestic water heater in a city apartment. The result of improper boiler steel strapping broken doors and broken wall is not only the owners of technology, but also in neighboring countries

When using the standard safety valve for domestic water heater is different: if a critical pressure level in the spring device is compressed and discharged to the outside portion liquid.

With this balanced pressure within the system equipment and heating continues normally. For this reason, installation of the fuse is obligatory and regulated by the installation requirements.

Thus, the security device performs a number of functions that are important for the normal operation of the boiler.

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Protection against water hammer and increases the critical pressure

The main function - to protect equipment from damage that may occur due to the increase of pressure in a centralized or house network

Duplication check valve action

The case where the pressure in the cold water system abruptly drops, the spring design will block the water and will not allow liquid to drain back into the conduit

Forced discharge of water from the boiler

With a small lever mechanism can be drained from the tank to be cleaned or repaired

Compliance with technical performance standards

Due to the safety node is an increase in the level of safety of the heating equipment at differences in temperature and pressure

Protection against water hammer and increases the critical pressure

Protection against water hammer and increases the critical pressure

Duplication check valve action

Duplication check valve action

Forced discharge of water from the boiler

Forced discharge of water from the boiler

Compliance with technical performance standards

Compliance with technical performance standards

Boiler manufacturers strongly recommend professional installation of water heaters. If this is not possible, then all installation steps must take place strictly according to instructions, with all the rules and the mandatory installation of the safety module.

Tips for choosing a valve model

As already mentioned above, the heaters are commercially available with a safety valve. Therefore, when purchasing a new model, especially brand, to take care of selecting the items you need.

Need to purchase arises in three cases:

  • you got to have a used boiler without binding elements;
  • Fuse lost when moving;
  • the valve is broken or worn.

Knowing the model of the boiler, you can easily pick up a new element. The operating instructions of the device parameters can be found ultimate pressure - the same should be stamped on the package of the new part.

Nominal pressure of the valve

A valve with a lower limit pressure or, conversely, does not need to buy stock. In the first case, you will observe a permanent leak from the tank, in the second - the valve just does not work in case of emergency

Thread diameter should match the dimensions of the mounting fitting and the cold-water conduit. Furthermore the device itself need linen thread on the tube or rubber gasket when using flexible hoses.

Sometime between the boiler pipe and fuse set valve to drain the water. It is permissible, the permissible piping arrangement, but one condition - the valve must be mounted on horizontal retraction from the water supply line. No locking devices between the safety valve and the cylinder should not be.

Installation instructions for the boiler piping

Installing protective safety valve is one of the stages of the boiler piping. The minimum set of parts for the cold-water supply line - polypropylene Pipes and a safety valve.

But we will consider another option, in which, besides the name of the elements involved tee, drain cock and American. In addition, the required PP fittings in order to displace the water supply line to the wall.

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Step 1 - Installation of a tee for the drain cock

The first part - a brass tee on ½ inch required to mount the check valve. It is attached by means of a tow and a special paste, spinning at 3-4 turnover

Step 2 - Installation of the shut-off valve at the tap

The shut-off valve is required to organize a further draining for repair and maintenance work. Without it you can not install a tee

Step 3 - selection or preparation of a safety valve

Metal valve taken from the starter kit as a new boiler. You should carefully inspect it from all sides, check availability and serviceability of the lever springs

Step 4 - the correct location of the fuse on the tube

On the surface of the body from one side embossed arrow indicating a direction according to which the water has to move. The device must be secured on the tube so that the arrow pointing up, and a hole for draining - down

Step 5 - Installation of safety valve on the tee

Secure the valve threaded connection, all using the same tow and assembly paste. If there is an emergency discharge of excess water from the tank, it flows from down hole

Step 6 - Set the "American" for connection with the pipe

Directly to the safety valve screwed, "an American" - shut-off valve. To lock the coupling nut is used with a rubber liner. The second tube boiler also establish "an American"

Step 7 - Installation of PP adapters

Adapters are needed to ward off the water supply line close to the wall. If they do not interfere, the polypropylene pipes are fixed directly to the lower gate - "American"

Step 8 - Connect to cold water system

Plastic, usually polypropylene, pipe and attached by welding by means of fittings. It remains connected to the fuse drain pipe

Step 1 - Installation of a tee for the drain cock

Step 1 - Installation of a tee for the drain cock

Step 2 - Installation of the shut-off valve at the tap

Step 2 - Installation of the shut-off valve at the tap

Step 3 - selection or preparation of a safety valve

Step 3 - selection or preparation of a safety valve

Step 4 - the correct location of the fuse on the tube

Step 4 - the correct location of the fuse on the tube

Step 5 - Installation of safety valve on the tee

Step 5 - Installation of safety valve on the tee

Step 6 - Set the "American" for connection with the pipe

Step 6 - Set the "American" for connection with the pipe

Step 7 - Installation of PP adapters

Step 7 - Installation of PP adapters

Step 8 - Connect to cold water system

Step 8 - Connect to cold water system

Sophisticated safety node is not always used. Some installers believe that only one safety valve. This is the minimum version of the boiler piping.

If you do not use tees or other adapter, the fuse is fixed directly to the boiler pipe. He can hide behind the casing or 1-2 cm below the sink, it is more convenient to connect.

Installation of the valve in the connecting pipe

installation option when the safety device is strung directly on the boiler fitting. Thread both elements - ½ inches. It used for sealing a tow, which is considered particularly for such compounds better fum ribbons

It remains to ensure the water drain through the opening in the guard. For this purpose, a flexible plastic tube of suitable diameter. It can be white, colored or transparent.

One tube end is put on mini-nozzle valve, a second tee output to the sewer or directly to the outlet. Consider options for installation.

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Plastic tube to drain fluid

The transparent tube is good because it provides an opportunity to observe the process fluid drain into the sewer. You can determine the approximate amount of discharged liquid

Undermining water from openings

If you do not set up, from time to time, the water dripping from the hole will fall on the floor or furniture, to create a high moisture content and conditions for the development of mold and mildew

Installing a tube and shut-off valve

With such a harness forced draining can be achieved using the retraction and shutoff valve, installed specially for this purpose. The safety device works only for its intended purpose

Option to connect to the sewer pipe

If the hand was not tee, which is inserted into the sewer pipe, the discharge pipe is mounted directly soldered a short tube and providing connections for leaks

Plastic tube to drain fluid

Plastic tube to drain fluid

Undermining water from openings

Undermining water from openings

Installing a tube and shut-off valve

Installing a tube and shut-off valve

Option to connect to the sewer pipe

Option to connect to the sewer pipe

Improvident property owners lowered the drain pipe into a bucket or jar - it's wrong. If the capacity and save, it is only from the constant undermining.

In an emergency, the volume of water moving through the tube increases, and the capacity may not be enough. The only true solution - outlet drain to the sewer pipe by inserting a tee or a separate input.

Professional installation recommendations

Even such a simple procedure as the installation of valves is based on the implementation of certain rules. For example, room design often requires masking of the pipeline, and security groups.

Hide device can be, but subject to three conditions:

  • Lenth liner or pipe from the tank to the fuse should not exceed 2 m, because otherwise there unnecessary additional pressure on the valve spring;
  • perfect fitting fuse - directly to the boiler fitting, and if not, then the installation of the tee is still excluded;
  • Technical hatch should be fitted for the service valves.

Many are worried to see a drop of water on the valve pipe. This is a normal phenomenon, stating the device performance.

From time to time there are small pressure fluctuations in the pipeline, which provoke minimum discharge liquid. You need to worry, when the water is or is not displayed, or is shed continuously.

The distance from the valve to the boiler

Section of the line between the water heater and the fuse should be minimal. This is necessary not for aesthetic reasons, and in order not to create additional pressure in pipes

It should be remembered that an independent modernization of the safety devices is strictly forbidden. If you want a valve to 0.8 MPa, it is necessary to buy just such a new product, rather than trying to somehow alter or adjust the unit to 0.7 MPa.

If any doubt about the performance of the safety valve should be dismantled it and see if the spring or seal are clogged. Having problems with the water heater itself, and you do not know what to do? We recommend you visit frequently breakdowns and boiler repair. Lack the skills - to invite an expert from the service center.

Conclusions and useful videos on the topic

To stop the installation process and the safety valve to flow smoothly, without errors and misunderstandings, before installing the valves and other devices read the experiences of seasoned boilers owners.

Once again on the construction and operation of:

A few things that you can take note of:

As with any fittings for binding, the safety valve device is required for correct operation of the heater. It should not be confused with non-return valve and should only be installed according to the instructions.

If you are having difficulty with the selection or installation, please refer to experienced professionals, who for half an hour will your boiler in full readiness.

Do you want to understand the purpose of the safety valve and the subtleties of its installation? Maybe you still have questions after reading this article? Do not be shy - ask advice from our experts in the comment block.

If you specialize in the installation of boilers and their maintenance and repair, and noticed a discrepancy in our material or want to supplement said howto - please write your feedback to this Article.

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