Emergency valve of pressure discharge in the heating system

An dependable heating system is crucial for maintaining a warm and cozy home. However, unexpected problems can arise with any system. The emergency pressure discharge valve is a crucial part of a heating system. This little but powerful valve is essential to preserving the effectiveness and safety of your heating system.

Imagine that your heating system is working very hard to keep your house warm on a chilly winter’s night. Abruptly, you detect an odd hissing noise emanating from the boiler. Though panic may be your first reaction, relax—it’spossiblethat the sound is the emergency pressure discharge valve in action. This valve’s purpose is to relieve the system of excess pressure, averting potentially hazardous scenarios like explosions or boiler damage.

How then does this valve function? Think of your heating system as a steam or hot water-filled, tightly sealed container. The water expands as it warms up, building pressure within the system. Under normal circumstances, the boiler’s controls regulate this pressure. But in the event of a problem, such as a broken thermostat or a blockage in the pipes, the pressure can rise dangerously fast. The emergency pressure discharge valve comes into play in this situation.

Consider the emergency pressure discharge valve to be a kind of safety release. The valve automatically opens to allow excess pressure to leave the system safely when the pressure reaches a predetermined threshold. During an emergency discharge event, you may hear a hissing sound due to a sudden release of pressure. Although it may cause concern, this indicates that the valve is protecting both your house and your heating system.

It’s crucial to keep in mind nevertheless that the emergency pressure discharge valve is not a panacea. It is not a replacement for routine maintenance and care of your heating system; rather, it is your last line of defense against catastrophic failure. Your home can remain warm, secure, and comfortable all year long with the help of routine inspections by trained specialists who can spot possible problems before they become emergencies.

Select a safety valve for heating: types, characteristics and installation

Obstructed heating valves

It’s possible that the autonomous heating system won’t always run steadily. The integrity of the pipe and radiator connection is impacted by sudden changes in temperature and pressure. A safety valve for the heating system is the specific protective device required to stop this; choosing and installing one is part of the required list of installation tasks.

The functions of the bypass valve

Coolant expands when heated; this naturally occurring increase in volume raises the pressure inside pipelines and heating apparatus walls. When a threshold is exceeded, typically around 3.5 bar, the joints’ tightness is disrupted, resulting in gusts and emergency scenarios. Installing the bypass, also known as the heating boiler’s valve safety, is essential for the prompt discharge of excess hot water.

It needs to carry out the following duties:

  • Timely remove the excess of the coolant, while reducing the pressure inside the system;
  • Have the ability to set up. In the autonomous system of a private house, a safety valve for heating should have a manual setting function of the maximum permissible pressure value;
  • Reliability of operation. The design and material of manufacture should ensure the normal operation of the safety valve for the heating system.

The heat supply parameters, such as the length of the highway and its type (collector, two-pipe, or single-pipe), the location of the expansion tank, and the value of the optimal and maximum pressure in the pipes, all affect which model is selected. However, you should research the features of the heating safety valve, such as its design, installation specificity, and operating principle, before making a purchase.

Types and features of valves design for heating

These days, there are two distinct operational principles used for bypass valves: spring and lever-carbonate. For large central heating highways, the latter is most frequently utilized. Think about the particulars of each person’s work.

Spring valves


Private homes and apartments have this heating system’s discharge safety valve installed.

This mechanism works on the following principle. The kapan’s shutter, whose movement is restricted to the spring, is impacted by the fluid flow. The rod will rise up as soon as the pressure value is greater than the spring’s compression force. The coolant will consequently enter the output pipe. The heating boiler’s safety valve will reset the shutter to its initial position once the internal water volume has stabilized. Consequently, the coolant flow stops entering the output pipe.

Lever-carrier valve

The large diameter (beginning at 200 mm) pipelines are fitted with this kind of reset safety device. It uses a force on the stem to exert a load with a different mass in place of a spring.

You need to become familiar with the details of how a heating system works before selecting a safety valve for one with a similar design. First of all, the critical pressure value is set roughly. This can be accomplished by adjusting the external lever’s mass. This can be accomplished in spring models by looking at the control cap. Furthermore, there can be a minimum 0.2 bar change in the pressure value.

As with any heating system, safety comes first. One essential part that keeps the system safe from potential harm from an excessive build-up of pressure is the emergency pressure discharge valve. By serving as a safety release, this valve keeps the system’s pressure from building to levels that could cause leaks, bursts, or other hazards. Its basic yet essential function is to automatically open the valve when the system’s pressure reaches a safe threshold, releasing excess pressure and protecting the system’s occupants. This valve needs to be inspected and maintained on a regular basis to guarantee both the heating system’s overall safety and proper operation.

Choose the optimal model

A section’s spring safety valve

The operational characteristics of the heating system should be the basis for choosing the safety valve. To accomplish this, you must become familiar with the regulatory document GOST 24570-81, which details the selection criteria in detail, in addition to the heating parameters.

Large pipelines employ lever-carbon mechanisms, so the requirements for the spring valve models of the heating boiler will be taken into consideration. They are broken down into multiple primary categories, including pipeline, manufacturing material, and mechanism requirements.

The three primary components of the bypass valve’s design—a spring, a rod, and a plate—affect the coolant pressure. When combined, they ought to create a dependable mechanism with carefully determined parameters. The primary ones are the installation, choice, and safety valve requirements for the heating system.

Differentiate between the two phases of the device’s operation: the moment the rod begins to move and the passage’s full opening to drain extra water. The primary feature of the valve is the percentage difference in pressure between them. Furthermore, it is contingent upon the heating system’s nominal pressure.

The device should operate more quickly the higher the working pressure. The heating safety valve spring’s turns shouldn’t come into contact with one another at the same time.

It is necessary to shield the adjusting mechanism from the direct heat of the water.

The device should have a mechanism for assessing its performance because it is possible to "stick" the spring with a long, simple (a rod for manually delaying the spring).

Submarine of the pipeline

You must accurately measure the diameter of the heating system before choosing a safety valve. It shouldn’t be any less than the pipe at the front. If not, hydraulic resistance will prevent the device from operating as intended. Because the effects of below-freezing temperatures are detrimental to work, make sure the heating system’s discharge safety valve is kept safe from freezing.

The heating system’s safety valve should be installed with a slope that only faces the boiler. This will result in very little hydraulic loss when the plate is under pressure.

Production material

Brass is the most commonly used material for cases because it is affordable, dependable, and has a minimum temperature expansion coefficient. It is crucial to choose the heating system’s safety valve based on this parameter since the case shouldn’t be destroyed when the maximum pressure is reached.

The timely setting of the operation’s value is also the fundamental principle of operation for a safety heating valve. The unit is made of a unique heat-resistant plastic to enable quick adjustments. Even at the highest water temperature, he maintains his toughness without altering his geometry.

Features of the installation of the safety valve

Circuit for heating with a fixed safety valve

When a safety valve is professionally installed in a heating system, its features are taken into consideration, along with the expansion tank’s operation. The bypass valve should function and clear the pipes of extra water as soon as the latter is unable to increase the internal volume of the pipes.

The heating system’s safety valve (elements 3 and 4 on the diagram) needs to be installed right after the boiler pipe’s output in accordance with reset regulations. They should be 20 to 30 centimeters apart at their best. A manometer is mounted in front of it for visual control. His indications allow one to ascertain the system’s current state.

When installing a safety valve in the heating system, follow these guidelines:

  • Before the device and boiler, you cannot mount locking equipment – valves, taps, etc.D.;
  • To remove the excess water on the output pipe of the correctly selected safety valve of heating, a drain tube is installed. It can be connected to a reverse or sewer pipe;
  • In a closed gravitational system, the safety heating valve is installed at the highest point.

Furthermore, it is imperative to conduct periodic assessments of the mechanism’s condition. The plate "sticking" to the case walls is a defining feature of the spring models. As a result, the heating system’s safety valve’s maximum pressure is increased. Consequently, the device will not function if the valid pressure is higher than the allowable pressure.

It is advised by experts to replace the valve if there were seven or eight emergency descents. The spring and plate wear that occurs naturally is the cause of this.

The latter speaks more to the conditions under which the heating safety valve operates than to the basic idea behind it. Without it, though, there’s a greater chance that the device won’t work correctly even with a flawless installation.

When choosing a safety valve for an autonomous heating system, what factors should be taken into account? Conformity with the operational’s technical specifications. Making the correct connection between it and the nozzle is also crucial. The best option for this is to use a conventional pipe packet. There might be a leak because the FUM tape can’t tolerate temperature exposure.

Watching this video will help you better understand the safety valve’s operating principle. It explains the characteristics of the spring model’s design and operation.

How to choose a safety valve in the pressure in the boiler

Water in the boiler and pipelines heats up to a critical temperature if the heating is not controlled. As a result, the water boils and enters the steam phase, increasing network pressure. The highway or the heat generator’s sheathing bursts, filling the entire room with steam. There is a safety valve that releases the pressure in the heating system beforehand to avert the situation mentioned. Thus, choosing this crucial component needs careful consideration—something that this information will assist you with.

Operating principle

The majority of common users of closed water heating systems are only acquainted with one kind of safety reinforcement, which is the straightforward spring valve in the picture with a fixed setting. It makes sense that these devices, which are installed on all boilers as part of the security group along with the pressure gauge and air venture, would be installed everywhere.

Note: Safety features are built into wall heat generators that run on natural gas or electricity right out of the factory. They are positioned within the case so that they are hidden from view.

Let’s examine how the typical emergency valve depicted in the diagram above operates:

  1. Under normal conditions, the membrane attached to the rod and propped up by the spring sits tightly in the saddle and hermetically overlap the passage.
  2. If the coolant is overheated, it expands and creates excess pressure in a closed system, partially compensated by the expansion tank.
  3. Когда величина подпора воды достигает порога срабатывания клапана (обычно – 3 Бар), пружина под ее воздействием сжимается и мембрана открывает проход. Automatic discharge of boiling coolant is made until the spring is enough strength to close the passage again.
  4. In the event of an emergency, the owner of the house can himself discharge excess pressure, turning the handle in the upper part of the product.

A few words regarding the location of the discharge valve’s security group in a closed heating system. Its location is along the feeding line, right next to the boiler (a maximum of 0.5 meters is advised).

A crucial aspect. Installing taps, valves, or other overlapping devices in the pipeline that connects the heat generator to the safety elements is prohibited.

Tightly connecting the product pipe to the sewer is not worth it because puddles or wet stains will reveal issues with the valve and the heating network. When using a solid fuel boiler, for instance, an expansion tank or circulation pump may have failed (possibly turned off electricity). Garbage between the saddle and plate is often the reason why the device starts to leak. The video tells more about his work:

Information clarification. Because the coolant pressure compresses the spring and undermines the membrane, the discharge spring valves of the masters and installers are referred to as subversive. They should not be confused with explosive devices that are placed on the chimneys of commercial natural gas boilers.

Types of safety valves

The above-mentioned traditional subversive design is not flawless. The spring mechanism, which is powered by high pressure, is accurate and can operate slowly once the boiler tank’s temperature reaches 100 °C or higher—that is, when a boil starts. Of course, you can try to modify the product’s settings or tighten the screw (some models have an adjusting cap), but sometimes this won’t have the desired effect.

Second moment: the boiler’s safety valve guards against damage but not overheating. After all, if the furnace’s combustion continues, the coolant discharge cannot be used to cool the heating unit. Finally, since water in them can boil without creating pressure, these devices are usually pointless in open-type heating systems.

Prominent producers of heating reinforcement provide cutting-edge products free of the specified flaws, such as heat discharge valves. These safety features respond when the system’s water temperature rises to a critical point rather than when the system’s water pressure rises. Three different product varieties exist:

  • reset with a remote temperature sensor;
  • a combined device with a temperature sensor and a recharge circuit;
  • The same with a direct installation in the pipeline.

As a point of reference. These are the names of trustworthy companies whose emergency reinforcement is safe to purchase and use in homes. These are the producers of Herz Armaturen (Austria), ICMA and CALEFFI (Italy), and the renowned European brand Danfoss.

All varieties work on the same principle: a bellif filled with a thermally sensitive fluid that expands significantly when heated drives a spring mechanism with one or more membranes. In this manner, when a critical temperature is reached, the heat discharge valves respond fairly accurately. We propose to take a closer look at each of them.

Element with a remote sensor

The product is the same spring mechanism that is integrated into the case and has two pipes that connect to the sewer and feeding line, respectively. Furs (2 groups – main and backup) are moved by a rod that opens a plate and road to the coolant. Thermosensitive fluid from a capillary tube sensor presses them when water overheats (beta 95 to 100 °C). The figure depicts the safety element’s design:

There are three ways in which a solid fuel boiler’s temperature valve is strapped in:

  • with cooling through the water circuit of the heat generator;
  • The same, through a special emergency heat exchanger;
  • Coarrous reset with automatic subtopics.

Double-circuit heating plants that supply water for hydraulic devices use the first scheme shown below. The hot water from the contour merges into the sewer and takes the place of the cold water from the water supply when a sensor positioned beneath the surface of a TT-boiler activates the mechanism. Such a functioning system will promptly cool the boiler shirt and avert the consequences, regardless of the accident’s causes.

Note: The publication uses CALEFFI brand schemes that are sourced from the manufacturer’s official website.

With an integrated emergency heat exchanger for cooling in the event of overheating, the second circuit is intended for use with heat generators. European brands such as Di Dietrich and Atmos produce these units.

The most recent circuit can only be used in conjunction with the automatic recharge system because in this case the valve releases coolant rather than cooling water.

As you can see, the manufacturer permits the installation of two emergency devices: a reset valve and a security group that operate under pressure.

Caution. When using cast iron fuel in a wood-like heater, automatic feeding is not advised. The latter is prone to cracking when exposed to sudden changes in temperature, such as when a large volume of cold water is supplied.

Combined products with system subscription

This brilliant emergency reinforcement representative carries out three tasks simultaneously and operates similarly to bypass valves in theory:

  1. Reset of the overheated coolant from the boiler tank at the signal of the remote sensor.
  2. Effective cooling of the heat generator.
  3. Automatic recharge of the heating system with cold water.

The product’s design is seen in the picture above, where two plates are mounted on a single rod and two passes are opened simultaneously. The first passes release boiling coolant, while the second pass replenishes losses by releasing water in the opposite direction. The combined bypass valve connection diagram for a solid fuel boiler looks like this:

Note: The duct must be organized through an indirect heating boiler or an open expansion tank if you must use this type of device to cool a TT-cat with a cast-iron heat exchanger.

The triple output bypass valve only integrates directly into the heat carrier supply pipeline close to the heating unit, but it functions based on the same combined principle. The section of the case that is inside the pipe is where the bell tower is situated. The water supply and the recharge line are connected to the two upper pipes, and the reset is completed through the lower pipe. These products are utilized when there is not enough room in the boiler room.

How to choose emergency reinforcement

Of course, the traditional subversive valve will be less expensive to buy and install than temperature sensors. A closed heating system connected to an electric, gas, or diesel boiler will be easily protected by him because, in the event of an accident, the boilers will cease to heat almost immediately. An additional item is a heat generator that is fixed to the angle and wood.

Use these suggestions as a guide to properly select the excess pressure or heat discharge valve:

  1. When using any energy carriers, except for solid fuel, feel free to buy a conventional subversive device.
  2. Explore the documentation of your heat or boiler source (depending on what you need to protect) and choose the safety reinforcement according to the maximum permissible pressure indicated in it. Most of the heating equipment is designed for the limit of 3 bar, although there are exceptions – the Lithuanian boilers Stropuva withstand only 2 bar, and some Russian units (from inexpensive) – 1.5 bar.
  3. For effective cooling of wood heat generators in the event of an accident, it is better to put one of the heat discharge valves. Their maximum operating pressure is 10 bar.
  4. In open systems with TT-Kotl, the discharge of pressure is useless. Choose a safety product that works at a coolant temperature of 95-100 ° C, suitable for your unit and a method.

Suggestions. Avoid purchasing inexpensive safety reinforcement from China. It is not only untrustworthy, but it keeps on undermining after the initial attempt.

In addition to products with fixed settings, there are valves on sale with the ability to adjust. If you are not a professional in the field of heating, then you should not buy them, and there is no particular need.

Tips finally

If you have a strong interest in the boiler room’s security and the dependable operation of the heating system, we advise you to research the selection carefully before making your purchase of reinforcement. It is a fact that new and useful products that are not visible in the context of this article come out on the market and could be useful.

Moment of operation. Monitor the condition of safety valves to identify malfunctions early and determine the causes. A sudden splash of water in the boiler room and wet traces will indicate that there was an emergency. Devices for thermal discharge direct to the sewer funnel with a jet gap.

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Heating systems> How to select a safety valve for the boiler’s pressure

Emergency valve in the heating system

When the heating system is operating, the emergency valve of the pressure discharge is utilized to stop potentially dangerous situations from happening. They may cause a network malfunction or the equipment to be placed incorrectly. This means that not only could individual components fail, but the entire engineering network could as well. Furthermore, circumstances that endanger human life and health occur.

Purpose and principle of operation of emergency valves

Two types of valves are lever-carbon and spring.

The device is intended to shield the engineering network from excessive pressure, as was mentioned at the outset. There is a risk to heating systems that have steam boiler units. A rise in pressure is evident in the hot water supply network and the self-contained building heating system. Primary causes of increasing pressure:

  • a sharp jump in the temperature of the water, which eventually turns into steam (observed when the liquid is descent from the pipeline);
  • Excessive amount of the coolant, which is used as a system of the system (it happens when the automation works incorrectly).

It is vital to take into account both types of equipment in order to comprehend the principle of work. The emergency valve may be operated by a lever or spring load. The first kind is different from the second in that a spring creates the force on the spool. The spring mechanism is compressed in order to regulate it.

The valve will open when the system’s water pressure exceeds the spring’s pressure per spool.

The water in the pipes where the valve is cut will then pass through the drain after that. For the following reasons, the spring type is more frequently used in small heating systems:

  • compact dimensions;
  • closed access to a change in the setting of the device without a tool, which increases the safety of its use;
  • There is no need to hold the stitching rod vertically;
  • use with other devices, for example, the crane of Maevsky.

Regarding the lever-loading emergency valve for pressure release, its working principle is comparable to that of a spring. The lever applies the pressure on the stem, which is the only distinction.

When all things are considered, the best choice is for a private home to have its own gas heating system.

Check out this article to find out how much a private home’s autonomous electric heating will cost.

Where the emergency valve is installed

Spout valve.

You can determine the location of the valve based on the product’s intended use. It’s important to realize that installing such a product is not always necessary. You can decline installation if there is an electric boiler in the home because this type of heating system does not need a discharge device. This is because these heat-generating installations have automation in place to keep an eye on safety.

In the following situations, an emergency valve must be present:

Installing the device on the feed pipe should happen right after the heat generator. In the event that a water supply network rather than heating is taken into consideration, the valve in this scenario is installed at the heated water’s outlet at the heater’s highest point. It should be known that mounting additional locking devices and regulation equipment in between multiple protection devices is strictly prohibited.

It is advised to connect the withdrawal to the emergency valve in order to prevent coolant from spraying into the room. Thus, the water will enter the sewer straight away. Installing the drain funnel, which provides a view of the jet gap, is recommended if it is necessary to have visual control over the process.

These days, autonomous heating in apartment buildings is more common than unusual.

Here is where you can learn about alternative country house heating sources.

Emergency Valve Pressure Discharge
Automatically releases pressure Prevents system overpressure

The emergency pressure discharge valve is an essential part of maintaining the effectiveness and safety of your home’s heating system. This tiny but essential device serves as a safety measure, keeping your heating system from experiencing potentially disastrous overpressure situations. It assists in preserving the integrity of the system and safeguards your property and its occupants by quickly relieving excess pressure.

You run the risk of damaging or even failing your heating system if you don’t have a working pressure discharge valve. Overly high pressure can cause leaks, bursts, or other problems that need expensive repairs and possibly cause downtime when you need your heating system most in the winter. Purchasing a dependable emergency valve is an anticipatory action that can ultimately save you a great deal of trouble and money.

Maintaining the continuous efficacy of your heating system necessitates routine maintenance and inspection, which includes the pressure discharge valve. Simple actions like inspecting for leaks, testing the valve’s operation, and removing any obstructions can significantly reduce the likelihood of issues developing later on. To guarantee correct repair or replacement, it’s also essential to take quick action on any problems and, if necessary, seek the assistance of a trained expert.

In summary, even though the emergency pressure discharge valve on your heating system might seem like a little part, its importance in preserving functionality and safety cannot be emphasized. You can have peace of mind knowing that your house is prepared to withstand unforeseen pressure fluctuations by realizing its significance and taking proactive measures to ensure proper operation. Don’t ignore this important part of house maintenance; take the required safety measures to preserve your heating system and your investment.

Video on the topic

Part-1 emergency safety heating valve, its work.

The operation of the discharge valve of the excessive pressure of the water in the heating system.

Novelty! Sutting valves Stout

Block for heating systems

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