Setting of safety valves for the boiler

Maintaining the safety of your home’s heating system is essential for safeguarding your belongings and the people you love. The boiler, the central component of many heating systems, is one important part in this regard. Safety valves in the boiler are essential for averting overpressure scenarios that might result in disastrous breakdowns. Maintaining a safe and effective heating system requires knowing how to set and maintain these safety valves correctly.

Pressure is an important consideration in a boiler’s operation. Excessive pressure can cause explosions, boiler damage, and leaks. Safety valves automatically release excess pressure before it reaches dangerous levels, serving as the last line of defense against such situations. You can feel secure knowing that your boiler is operating within safe bounds during the heating season thanks to precisely calibrated safety valves.

A boiler’s safety valves must be set carefully and precisely. It entails adjusting the valve to release pressure at the proper threshold, which is usually established by the local laws and the boiler’s design specifications. Although this task may appear difficult, particularly to individuals who are not familiar with boiler mechanics, it is a doable procedure that can be completed by competent homeowners or professionals with the necessary training.

Safety valves must receive routine maintenance in order to remain effective. These vital parts may experience performance issues due to wear and tear, corrosion, or debris accumulation over time. Regular testing and inspections aid in the early detection of any problems, enabling timely replacements or repairs as necessary. You can extend the life of your boiler and protect it from future problems by performing routine maintenance.

Design and operating principle of the valve

Device safety valve:

• protective cover;
• outlet opening;
• seals;
• compression springs;
• cone;
• seat;
• pressure chamber.

The body is constructed using hot stamping technology, typically using brass, giving it a long lifespan. The plastic used to make the regulating block is heat-resistant and does not change shape. While safety valves come in a variety of forms, they all work on the same principle. The seat is in a closed position and is driven by a spring mechanism. The seat will open and coolant will be released if the pressure inside the pipeline is greater than the force applied by the compression spring.

Types of safety valves

These protective components are categorized in various ways.

Spring – the most common, used for small-sized boiler rooms. They have a simple and reliable design and the ability to easily adjust the operating pressure in the system. Also from the advantages can be distinguished low cost.
Lever safety devices are not very popular, because mainly the model range is represented by diameters from 50 mm. They are used in industrial applications.
Impulse devices are used on steam boilers with pressure greater than 39 kgf/kv.cm (3.9 MPa). At least 2 pcs. are installed on each boiler. (control and operating).
Low-lift have a valve lift height from 5% of the seat diameter, therefore they have a low flow capacity. Among the advantages are: simple construction, affordable price.

Ò full-lift At least 25% of the seat diameter is visible above the gate valve. They fall into the two-stage category. characterized by an expensive construction, a high flow capacity, and intricate design.

There is a bell on full-lift safety devices. Its job is to assist the gate in reaching its maximum lift. The primary applications for full-lift valves are in systems with compressible media. Proportional ones raise the gate in proportion to the rise in pressure, and they open the gate in proportion to the rise in the discharged medium’s volume. These protective devices are applied to liquid media, such as water.

The following are some benefits of employing a proportional valve:

• opening of the gate as required;
• lightweight construction;
• low cost;
• oscillations are automatically generated.

Safety devices with two stages instantly open the shutter. Installing them in the DHW circuit is prohibited because it causes the system’s pressure to drop, which causes the device to abruptly close and cause a hydraulic shock.

The gate’s auto-oscillation is a drawback of two-stage devices. The medium’s variable emergency flow rate or oversizing are to blame for this.

How to choose a reliable valve

It is necessary to specify the maximum allowable pressure limits in the heating system design. In addition, consideration is given to the volume, circulation, temperature, and productive capacity of the boiler or pump. The type and design elements are chosen in accordance with this. It is advised that users utilize spring-loaded safety relief valves among the varieties previously mentioned. They work flawlessly with low capacity boilers. Hot water systems can also use low or medium lift units.

An open type device ought to be chosen if the working medium is released into the surrounding area. A housing design with a threaded connection outlet is used if the discharge is to the drain.

Installing a safety device with an inflated operating threshold is prohibited. It won’t activate when it’s required.

The conventional blow-off valve is inexpensive and simple to install. This device provides excellent protection for closed heating systems with gas or electric boilers because it instantly cuts off heat in the event of an emergency. It is also not advised to buy inexpensive Chinese valves. It leaks right away after the first blow-up and is unreliable.

Place of installation of safety valves

When choosing a location for safety device installation, there are several guidelines to go by:

1. Pulse valves should be installed in closed rooms, taking into account the climate for which they are designed (temperate or tropical).
2. For maintenance, repair, assembly and disassembly of products it is recommended to organize the place so that these actions were without cutting out of the water supply system.
3. The installation must be carried out in accordance with the project drawings.
4. The main valve is mounted by welding to the connection only upwards vertically. A deviation is possible, but not more than 0.2 mm per 100 mm of the height of the safety device.
5. When welding, prevent splashes, hail, scale from entering the valve cavity.
6. Seams after cooking need heat treatment, based on the requirements of the current instruction for installation of equipment of the water supply system.
7. No shut-off devices or filters may be installed on the pipes approaching the valve or in the pressure relief pipelines.
8. The valve lever must be installed horizontally.
9. In order to control the head, a pressure gauge must be placed in front of the fitting.
10. The valve for the heating system can be mounted in several places in the pipeline.

Adjustment of safety valves

Safety device adjustments are carried out following system installation and flushing.

Several steps are taken to check the safety relief valves:

1. Adjustment of the pressure, which is set slightly above the limit operating pressure.
2. Checking the head when opening, it must not exceed the minimum pressure. Corresponds to normal operation. The pressure in the spring-loaded safety relief valve can be adjusted by turning the adjusting screw, which compresses the spring. The lever valve is adjusted by changing the weight of the weight.
3. Check for full opening and closing.

Safety devices whose manufacturers have set the pressure cannot have their adjustments made. If the gate opens and closes smoothly, the air and water tightness are guaranteed, and the deviations in the opening and closing pressures are within the allowed limits for this kind of valve, then the safety valve is ready for use (refer to the device passport).

Safety valves should be checked periodically, once every quarter.

Once all adjustments have been made, the adjustment must be sealed. An operating card or technological passport should be created and placed on the safety device’s body, or on a plate that is welded to the valve’s body and indicates the installation location and pressure.

One essential component of home efficiency and safety is setting the safety valves on your boiler. These valves are essential in preventing the boiler’s internal pressure from building up, which could result in hazardous scenarios like explosions or leaks. Your heating system will run smoothly and safely if these valves are set and maintained correctly.

Controlling the pressure inside the boiler is one of the main purposes of installing safety valves. The valve opens to release extra steam or water to relieve pressure when the pressure reaches a predetermined threshold. This keeps the boiler from building pressure to dangerous levels that could harm your house or its occupants.

It’s imperative that you set the safety valves in accordance with the manufacturer’s instructions. Usually, these recommendations include suggested pressure ranges and how to set the valves appropriately. You can guarantee that your boiler operates within safe bounds and reduce the possibility of mishaps or malfunctions by following these recommendations.

Maintaining safety valves effectively requires routine maintenance. The proper functioning of valves can be compromised by rust or wear over time. As a result, it’s critical to routinely check and test the valves to make sure they’re functioning properly. This may entail cleaning up any debris, inspecting for leaks, and modifying the settings as necessary.

In summary, installing safety valves on your boiler is essential for both efficiency and home safety, in addition to being required by law. You can safeguard your family and your house from potential dangers and maintain the best possible operation for your heating system by realizing their significance and taking the required actions to set and maintain them correctly.

We’ll go into great detail about the vital role safety valves play in maintaining the safe operation of your boiler in the article about setting safety valves for the boiler on our "Heating and Insulation of the House" website. Safety valves act as the boiler’s "guardians," keeping pressure from rising to potentially hazardous levels. When these valves are adjusted correctly, excess pressure is released at the appropriate time, averting possible explosions and boiler damage. We’ll talk about how crucial it is to perform routine maintenance and calibration on the valves to make sure they work properly and protect your family and house. The longevity and safety of your boiler system can be significantly affected by knowing how to set these valves correctly.

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