How to install a membrane expansion tank for heating

Maintaining a dependable boiler or furnace is not the only thing needed to ensure effective heating in your house. The goal is to optimize every part of the system, including expansion tanks. These tanks are essential for controlling pressure swings in your heating system, protecting it from harm and guaranteeing reliable operation.

Although installing a membrane expansion tank may seem difficult at first, many homeowners can handle the task with the correct assistance. Maintaining a cozy and energy-efficient home requires knowing the fundamentals of these tanks’ operation and proper installation, whether you’re installing a new heating system or replacing an old one.

Understanding why your heating system needs an expansion tank is crucial before beginning the installation process. To avoid damaging pipes, valves, and other parts, the pressure that is created when water heats up and expands must be released. By providing a dedicated area for this expanded water to go, expansion tanks help the system’s pressure stay constant.

In particular, a flexible membrane is used in membrane expansion tanks to keep the water and air cushion inside the tank apart. More effective pressure control is made possible by this design, which also reduces the possibility of waterlogging—a situation in which the tank overflows with water and becomes incapable of adjusting to changes in pressure. It is essential to comprehend this idea in order to guarantee that your heating system operates as intended.

Let’s now examine how to install a membrane expansion tank for your heating system step-by-step. You can prolong the life and improve the performance of your home heating system, giving you comfort and peace of mind for many years to come, by carefully following these instructions and taking the required safety measures.

Step	Description
1	Choose a suitable location for the expansion tank near the boiler or heating system.
2	Turn off the power to the boiler and let it cool down before starting the installation.
3	Shut off the water supply to the heating system.
4	Drain the water from the heating system to relieve pressure.
5	Install a tee fitting into the supply line near the boiler.
6	Connect the expansion tank to the tee fitting.
7	Secure the expansion tank in place, ensuring it is level.
8	Re-fill the heating system with water.
9	Check for any leaks and make necessary adjustments.
10	Turn the power back on to the boiler.
11	Test the expansion tank to ensure it"s functioning properly.

How to install a membrane expansion tank of a heating system

A membrane expansion tank is one of the heating system’s components. You can see how he looks in the picture. This apparatus is required to make up for variations in water volume brought on by heating. The tank body is divided into two sections by an elastic membrane; the first section contains a liquid coolant, and the second is filled with nitrogen or highly pressurized air.

Use of membrane expansion tanks

Membrane tanks are employed in the subsequent scenarios:

• when arranging heating systems for which autonomous heat sources are used;
• for the functioning of heating structures connected to centralized heat supply networks in accordance with the independent scheme;
• in systems where thermal awnings and solar collectors use;
• In the schemes of heat supply, in which there are closed contours and variable operating temperature.

Advantages of using membrane devices

There are several benefits associated with membrane expansion tanks in heating systems:

• Butyl membranes and natural rubber are allowed to be used in supplying drinking water;
• Devices are suitable for water of any quality, even for the one that contains a lot of calcium;
• If necessary, the membrane can be replaced without problems;
• The membrane expansion tank of the heating system compared to the pressure type that does not have it has a large volume to displace the fluid;
• There is no risk that drinking water will be contaminated;
• You need minimal air pumping;
• There are no heat -carrier losses as a result of evaporation;
• low operating costs;
• The installation of the tank is inexpensive and is performed quickly.

Structural features

The membrane expansion tank serves the function of ensuring that, during all operating phases, the device maintains the equilibrium between the pressures in both components and, if required, levels excessive pressure or controls its variations in the heating structure. As a result, installing a membrane expansion tank guards against higher loads in the heating circuit during emergencies or malfunctions.

The device comes with a membrane that is either fixed or replaceable. In the first scenario, the coolant cannot interact with the steel inner surface because it is entirely contained in a flexible membrane container. All tasks associated with disassembling and reassembling a new product are carried out via the flange fastened to the bolts.

If a device with a fixed diaphragm is purchased, it has an internal cavity consisting of two parts. In this case, a non -changing diaphragm membrane is used, which is rigidly recorded.
Choose a membrane tank for the heating system directly for a specific heating structure, taking into account the number of coolant. If the device is insufficient in the device, then the consequences can be the most negative – cracks often appear and water leaks are possible through the thread. In addition, the pressure often drops below the permissible norm in the system, as a result of which the air enters the tank. Therefore, the choice of the device should correspond to the necessary design parameters (more detailed: “We make a selection of an expansion tank for heating”).

In order to compensate for thermal expansion caused by changes in fluid temperature, an expanded membrane tank is utilized in heating systems to create a closed-type coolant circulation. This helps to avoid hydraulic shocks. You can see how tight the system is when the device is in constant mode because the pressure in the gas and water chambers is the same. This heating system expansion tank device has been tried and true over time, making it the most useful.

We are able to operate the tank for an extended period of time because corrosion won’t render it unsuitable due to the absence of aggressive gases in the water circulating along the contour. Since the pressure expansion device is kept in the boiler room, it doesn’t need to be kept from freezing.

Even though choosing a tank for a heating structure is a personal choice, keep in mind that:

• The initial pressure in the membrane tank for heat supply, connected to cold water supply, must exceed static pressure in the system by 30-50 kPa;
• The device has a spare coolant to ensure compensation for possible leaks.

Safety valves are incorporated into the system to guard against excessive pressure in the expansion tank and closed contour elements.

Installation of membrane expansion tanks

Read the installation instructions included in the technical documentation and familiarize yourself with them before installing an expansion membrane tank. Its entire volume is filled with excess gas pressure when it is first supplied. The tank is pumped under predetermined pressure prior to installation.

A safety valve must be installed. The membrane expansion tank’s connection diagram typically specifies that drainage should be set up prior to the device. The specialist ought to be assigned; in dire circumstances, his advice is required.

When installing something, there are a few things to consider:

• it is better to install the tank to the junction of the water supply. It is necessary to provide the ability to nourish the system and drain the coolant, while the room temperature cannot be below zero degrees;
• The installation location of the device should be load -bearing, since additional load on the product from the pipes and other elements is not allowed. Когда оно имеет объем 8-30 литров, его монтируют на стену, если больше, то модель устанавливают на пол (прочитайте также: «Монтаж и установка расширительного бака в системе отопления своими руками «).

Watch the following video as well regarding the heating system’s membrane expansion tanks:

To prevent electrolytic corrosion, the expansion membrane tank that is required for heating or water supply must be grounded. When one is not included in the circulation pump’s design, a check valve is positioned at the device’s entrance. A manometer and an autoclap to reduce air pressure are installed at the output.

Installation of an expansion tank in the heating system of open and closed type

Expandable or closed expansion tanks are used in modern heating systems to account for the coolant’s temperature expansion. These tanks come with installation and operating condition requirements, as well as a number of benefits and drawbacks.

The primary considerations for selecting and installing an expansion tank in a forced and natural coolant circulation heating system are covered in this article.

The tank’s primary parameter is its beneficial volume, which ought to be greater than the value of variations in the system’s volume brought on by the greatest temperature change.

Because coolant can expand and compress while in use, the fluid volume in the heating system is not constant. Pressure on the walls of pipelines and heating equipment increases when the coolant is heated, increasing its volume while maintaining the same internal system size. This can destroy the pipelines and heating equipment.

An expansion tank, also called an expansomat (from the English verb "Expanse," which means "expand"), is added to the heating system’s design in order to stabilize the pressure on the interior walls of the component parts and adjust for changes in fluid volume. Coolant expands and enters the expander when its volume exceeds the system’s internal space. It then returns to its original state when the temperature drops.

How to determine the required volume of the expander?

The expander’s volume ought to be greater than the required volume, which is the most coolant that can enter the tank as a result of the tank heating up.

The total volume of coolant in the system is first ascertained. The overall volume of the system is calculated by adding the internal volumes of all the pipes and cavities in the boiler, heating batteries, and shut-off valves. Using the information in Table 1, one can determine the volume of liquid in pipelines based on the pipe’s diameter. The product’s documentation, such as the manufacturer’s catalog or passport, contains information about the equipment cavities’ volume.

The volume of coolant in one epa meter of pipeline is determined in Table 1.

Additionally, using the information in Table 2, knowing the total volume of liquid will help determine the expander’s necessary volume. The system pressure is taken into consideration when selecting this value. The most of the values determines the necessary tank volume if the previously calculated value falls between the two tabular values.

The expansion tank’s necessary volume is calculated in Table 2.

If water is used as a coolant, the data in Tables 2 are reasonable. The table value of the total volume, which is different from water, is multiplied by a correction coefficient equal to the ratio of the used liquid’s density to that of water in the case of fluids with a coefficient of thermal expansion.

The main varieties of tanks

In the heating system, expanders come in two primary varieties:

An open-type expansion tank is a one-piece container that can communicate with the environment. To guarantee the fluid’s natural return to the pipeline when its temperature drops, a tank of this type must be installed at the system’s highest point.

Expander of the open type.

Sealed expanders It takes the shape of a sealed vessel that is partially filled with liquid and partially with gas or air under specific pressure. The gas is compressed and the liquid enters the expansomate when it gets heated. The liquid cools and then re-enters the system, filling the gas due to the volume difference.

Closed-style expansion reservoir.

Open extensor tank

Apart from its primary purposes of stabilizing pressure and compensating for volume, an open-type expanomate also serves to remove air from the system, replenish water in the event of a small leak, and replenish the system.

Open expanders are composed of polymeric materials or sheet steel and have a rectangular or cylindrical shape. The heating system’s upper point is where the open-type expansion tank installation is done, necessitating an extension of the heating pipelines’ overall length. The coolant in the tank is shielded from contaminants by a lid, which also allows access for maintenance.

The forced circulation system’s open expansion tank’s working principle and connection diagram.

The open extensor can be found in an attic, stairworm, or specialized box that is fixed to the house’s roof. The expanding line can be installed in a bathroom or other residential area of the building if the height of the house permits it. Insulating containers outside of the heated portion of the house is necessary to keep the system from losing heat.

Sheet metal was used to boil an open tank.

The principle of operation and installation features

It is essential to maintain water circulation in the open-type tank to prevent stagnation. To achieve this, a circuit with an expansion and circulation pipe is installed between it and the heat supply’s main highway; the latter’s hole is situated in the tank at a slightly lower level (about 50 mm). If the system uses forced circulation, the circuit must be cut before the pump installed on the reverse line can begin to circulate water. Air bubbles within the system can be expelled into the atmosphere through circulation.

Open extensor with a relay at the bottom and top levels.

Keep in mind that the aforementioned is accurate when installing the expander in the heating system with forced coolant circulation!

In the naturally circulating system, the expander connects at the top of the large pipeline to allow for the unrestricted release of air bubbles.

The control pipe emerges at the lowest coolant level from the tank, and the overflow, which is meant to remove extra fluid, emerges at the highest level. A straightforward crane opening on the control pipe can perform the level check. Water from the tap indicates that the tank’s level is higher than it should be. For this reason, it is possible to install the lower and upper level relays, which, in the event that the water level approaches the overflow point or is in danger of falling to the minimum value, will trigger a light or sound signal.

The expander’s beneficial volume can be calculated by multiplying its base by the height that separates the lowest and maximum levels. This value represents the additional water resulting from temperature expansion. It must match or surpass the necessary amount determined by utilizing Tables 1 and 2.

Advantages and disadvantages

The open-type expander’s primary benefits are as follows:

1. simplicity of design, which implies a relatively low cost;
2. performs the function of discharge of pressure and removal of air from the heating system.

Open expansion tanks’ drawbacks

1. special installation conditions providing for the installation of additional pipelines;
2. high heat loss and the need for thermal insulation;
3. direct contact with the atmosphere, which can cause corrosion of steel elements of the system;
4. Due to the possibility of evaporation, the system needs periodic replenishment of the coolant.

It should be mentioned that open-type tanks are less common in residential building heating systems as a result of the aforementioned drawbacks, with closed expanders becoming more and more common.

Closed -type expansion tank

A closed expansion tank is not connected to the atmosphere, in contrast to open expansomes. It is a hermetic steel vessel with a special valve that allows inert gas to be pumped through while it is partially filled with liquid. Closed tanks are classified as follows based on how the internal volume is separated:

Closed expanders in a range of dimensions.

Wesembrand

As wicked expanders lack a mechanical internal space separation, the coolant comes into direct contact with the gas. An external compressor or gas cylinder is used to maintain a specific pressure. Gas supply and dressing are automatically controlled.

During the period when rubber (rubber) membranes had low resource indicators and needed to be replaced frequently, wasmbuest tanks were widely used. They could function without a membrane, but the design was complicated by the requirement for a cylinder or compressor. At the moment, divided-membrane closed tanks are common.

Membranes

A flexible membrane is used in the construction of contemporary expanders to separate the liquid from the gas. Some expanders come equipped with:

1. plate membrane (diaphragm);
2. pear -shaped (balloon) membrane.

The plate, which is attached in the center of the tank, resembles a hemisphere in shape. The shape of the water is either convex or concave, depending on its temperature.

The diaphragm expander apparatus.

Grushevid is fastened at the opposite ends of the container and replicates the shape of the vessel. One characteristic of these cylinders is that the coolant never comes into contact with the walls because the liquid fills the flexible membrane that sits between the gas-pumped gas’s metal walls and the liquid. This lengthens the structure’s service life and prevents corrosion. The diaphragm tanks’ design prevents the membrane from being replaced, but this design permits it.

A pear-shaped membrane tank.

The more durable membranes found in butyl and ethylenepropylene expanders are utilized in contemporary expanders. A rubber that is no longer in use was previously used for these purposes but has a shorter lifespan.

Compressor-equipped tank operating system.

Advantages and disadvantages of membrane tanks

The following are membrane expanders’ drawbacks:

• high price;
• the need for periodic pumping of gas or air;
• the need to control the pressure in the system.

Among the benefits, the following are noteworthy:

• compact dimensions;
• minimum heat loss, lack of the need for thermal insulation;
• lack of direct contact of the coolant with the atmosphere (evaporation), which reduces the risk of formation, spread of corrosion and the need to fuel the system;
• the ability to work at high pressure;
• the ability to install almost anywhere.

The choice of a membrane expander

The necessary volume of liquid in the system is the primary membrane tank parameter, and it should be pre-calculated using tables 1 and 2. The volume of the tank must match or exceed the calculated value.

Many manufacturers offer flat expanders with the diaphragm in addition to the conventional oval shape. This type of tank is smaller and can be mounted in the gap between the wall and the room’s interior décor without taking up any valuable space.

Extensor flat.

The membrane, which is the primary component of a modern closed-type tank, is subject to manufacturing quality and parameter variations that affect its service life. The membrane’s primary attributes are:

• range of operating temperatures and pressures;
• material;
• diffusion stability.

Red paint is used on membrane tanks used in heating systems, while blue paint is used on water supply systems. Lower standards of hygiene and sanitation are presented by the expander membranes used in heating systems.

Rules for installing closed expanders

A heating expander was installed.

1. The installation of an expansion tank of a closed type in the heating system can be carried out at any point of the circuit, but it is optimal to install in front of the circulation pump (for heating system with forced circulation of the coolant).
2. Installation is allowed in any position, but the option with the upper fluid supply is preferable, since it allows you to naturally go out air bubbles. Such installation will ensure the operability of the tank even when the membrane ruptures.
3. If during the operation of the heating system it is found that the volume of the installed tank is not enough instead of its replacement to establish additional required sizes.
4. When switching from water to another coolant, you may need to replace the expansion tank with a more voluminous. It is possible to install an additional extensor.
5. Some models of heating boilers have a built -in expansion tank, in this case, the installation of additional is not required.
6. The installation of a closed expande in a heating system with natural circulation requires the installation of a “car carrier” (automatic float valve) at the top of the system for automatic air discharge when filling the system and during the boiler operation.

Operation of expanders

The following tasks are necessary to keep a membrane-type expansion tank functional:

1. regular visual inspection for the lack of corrosion;
2. Checking the integrity of the membrane;
3. Air pressure check (gas).

In order to maintain open-type tanks, it is necessary to check the fluid level, which should not drop below the minimum mark, and conduct an external inspection of the case and thermal insulation.

On the bracket is an expansion tank.

One of the keys to a residential building’s complete heating system operating dependably, continuously, and safely is the proper selection and installation of an expansion tank. These days, it is more common to install an expansion tank of the closed type with a diaphragm membrane since it is both reasonably priced and extremely convenient to use.

Decorative lattices for heating radiators is an interior solution.

• Optimal thermal insulation for heating pipes
• Self -insulation of heating pipes on the street
• Polyethylene pipes for heating private possessions

Proper connection and installation of an expansion tank

We can guarantee the heating system’s dependability and efficiency by installing an expansion tank. These kinds of devices are utilized in both open and closed systems, where the coolant is forced or circulated by gravity.

The functions of the expansion tank

For what purpose is the expansion tank mount? The heating system is filled with a fixed amount of liquid (water or antifreeze), which is prone to thermal expansion. This means that the increase in the temperature of the coolant inevitably leads to an increase in the pressure in the system. Since the pipes, radiators and other elements of the engineering structure are inelastic, increased pressure will lead to depressurization of the system – a breakthrough will occur in the weakest place. Water is characterized by low compressibility indicators, so a special device is built into the system – a membrane or open tank. Its function lies in the fact that with increasing pressure, air will be compressed. This makes it possible to provide protection against a hydraulic jacket. The installed expansion tank protects the system from excessive increase in pressure. The main task is to perform reliable installation of a tank for a closed -type heating system, membrane tanks are designed – they are a container with an elastic waterproof membrane inside, which divides the internal volume into two parts. A membrane is needed so that the air does not contact the coolant. Otherwise, it is not to avoid bulging a network and increasing the risk of corrosion of steel elements of the system. The open -type system is communicated with the atmosphere, due to which the air from the pipes is pulled. For this reason, the place of installation of an open tank is rigidly regulated – it should be located at the highest point of the system.

How to connect an expansion tank

How to make a reliable connection of the expansion tank in the open system. The open -type heating system is characterized by the fact that the movement of the coolant in it is ensured by convection. The principle of operation is as follows: the coolant heated by the boiler room is delivered straight to the highest point of the system, as a result of which it goes by gravity into heating radiators and, cooing, returns to the boiler through the “Reverse” pipeline. There is always dissolved oxygen in water, which is released during convection, which means that air bubbles strive upward. When considering this scheme, it becomes obvious that the only possible place of installation of the expansion tank is the upper point of the system. For a single -pipe system – this is the upper part of the accelerated manifold. The connection diagram of the membrane tank in the open -type heating system as a tank can be used any capacity of a suitable size from the material resistant to heating. The cover (not sealed) is needed for it only to protect against garbage in the system. If there was no small metal barrel at hand, the tank is welded from sheet steel 3-4 mm thick. The tank should be installed in compliance with some rules, in particular :

• The tank needs to be placed above the boiler unit and connect them with a vertical riser along which heated water is supplied;
• It is recommended to thermal casing of the tank to reduce heat loss, especially if the reservoir is in the not -insulated attic of the house.

The water in the tank evaporates over time and needs to be replenished on a regular basis. Any old bucket will work for this. The water supply pipe is cut to the location of the tank installation if it is situated in the attic, where access is difficult. An emergency overflow system is set up to prevent hot water from flooding the house in the event of an emergency. Although private property owners frequently simplify the process by removing the emergency overflow pipe through the wall or roof, it is typically connected to the sewage network.

Expande tank in a closed heating system

The plumbing system’s equipment is chosen during the design phase, with consideration given to the boiler unit’s performance specifications, pipeline lengths, and coolant volume. A plan is being created that shows where each system component, including the expansion tank, should be installed. A membrane device must be used in the closed-type heating system.

In a closed heating system, expand

When referencing the project to the current boiler room, it is crucial to consider the following factors:

• The tank should be placed in such a way as to provide normal access for installation and further maintenance. Floor models are not recommended to install close to the wall.
• If the device is mounted on the wall, it is advisable to place it at such a level that you can freely reach the air spool and a cutting tap. Usually the tank is placed under the ceiling of the room only if it is not possible to mount it at a convenient height.
• The supply pipe should not be located on the floor across the passage or suspended at the height of human height.
• Pipelines connected to the expansion tank must be attached to the wall. It is important to avoid the situation when the load from them and on the shut -off valves falls on the tank nozzles. The fastening of pipes and cranes separately simplifies the replacement of the expansion device in case of failure.

The expansion tank’s required volume must be determined during the equipment selection process. This parameter’s lowest value is one-tenth of the total volume of liquid that is flowing through the system. Using a larger capacity tank is acceptable. However, because it cannot adjust for the increased pressure in the system, an inadequately sized tank may cause issues.

Guidelines for the installation of an expansion tank

You can use the boiler unit’s thermal power as a starting point for approximations of the coolant volume in the system. For every kilowatt, 15 liters of fluid are used on average. Precise computations are performed considering the radiator volume, pipeline length, etc.D.

Crucial! Numerous gas and electric boiler models are mini-boiling, meaning they come pre-installed with an expansion tank and a pump for the coolant’s forced circulation. If the built-in membrane tank’s specifications are adequate to guarantee the operation and security of the current heating system, there is no need to buy a separate tank.

When buying a membrane expansion tank, be sure the model you choose has a safety valve installed so that high pressure is released automatically. In the event that the device’s design does not include this, you should purchase and install a safety valve in close proximity to the tank.

Where is it better to put a tank

An untwisted section of pipeline with laminar water flow—that is, minimal or nonexistent twist—is the ideal location for the installation of a membrane container. A spill zone by the circulation pump is a handy location.

Note: You can install an expansion tank at any convenient height for a closed heating system. Since it only serves as a fuse from hydraulic units, there is no need to dispose of it at the highest point. In contrast to an open-type heating system, air cranes—special valves—are used to remove the air that has accumulated in the pipeline.

Hydraulically speaking, it makes the most sense to place the membrane tank on the reverse highway with the circulation pump positioned between it and the boiler. Pumping apparatus will perform at peak efficiency in this scenario.

Diagram showing potential tank location

The heating system’s operational characteristics won’t be impacted if the tank is placed on the supply line, if that is what is preferred. However, because the polymer membrane will be in constant contact with the coolant—which has only been heated to 90 degrees—rather than the water that has been cooled to 45 to 60 degrees and then returned through the pipeline, the membrane tank itself will not last very long.

Take note! If the heating boiler runs on solid fuel, installing a membrane tank on the supply mainstone is not advised. There’s a chance that in an emergency, the boiler’s water will boil and steam will enter the tank. Since water steam and air are both compressed environments, the membrane cannot account for the thermal expansion of water.

Maintaining an effective and dependable heating system for your house requires installing a membrane expansion tank. These tanks aid in the prevention of pressure buildup, which can result in damage and inefficiency, by allowing water to expand as it warms up. When the tank is installed correctly, it works efficiently and gives you peace of mind and constant heating.

Getting all the tools and supplies needed is crucial before starting the installation process. Included in this are the fittings, a pressure gauge, a pipe cutter, wrenches, Teflon tape, and the expansion tank itself. By taking the time to prepare these things in advance, you can expedite the installation process and help prevent any needless delays.

After you have everything you need, it’s time to determine where the expansion tank should be placed. It ought to be mounted on the boiler’s supply side, ideally close to the boiler. Make sure the tank has adequate room and is accessible for any necessary future maintenance. Make sure the location is easily accessible and free of any obstacles.

Next, it’s imperative that you carefully follow the manufacturer’s instructions when installing the product. This include fastening the tank firmly into position, utilizing the right fittings to connect it to the heating system, and making sure all connections are tight and free of leaks. Your heating system will last longer if you take the time to do this correctly and avoid problems later on.

To make sure everything is operating as it should after the tank is installed, it is crucial to test the system’s pressure and look for any leaks. This can be accomplished by using a pressure gauge and adhering to the suggested pressure levels listed in the owner’s manual for your heating system. If everything looks good, you can feel secure in the knowledge that your heating system is prepared to keep your house cozy and warm and that your expansion tank is installed properly.

To sum up, setting up a membrane expansion tank for heating is an easy but important chore for keeping a dependable and effective heating system. You can make sure your tank works well and gives you reliable heating for many years to come by adhering to the above instructions and paying close attention to detail during the installation process.

We’ll walk you through the installation of a membrane expansion tank for your heating system in this article. Expansion tanks are essential for preserving the equilibrium of pressure in your heating system and guarding against damage caused by an accumulation of excess pressure. Although installing a membrane expansion tank isn’t particularly difficult, doing it right is crucial to guaranteeing the effectiveness and safety of your system. We’ll go over all the requirements, including where to put the tank and how to connect it to your heating system. You can prolong the life and improve the efficiency of your heating system while averting future problems by adhering to these recommendations.

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