Individual is a whole complex of devices, located in a separate room, including elements thermal equipment. It ensures the connection of these installations to the heating network, their transformation, control of heat consumption modes, operability, distribution by type of coolant consumption and regulation of its parameters.

Individual heating point

The thermal installation, which deals with or its individual parts, is an individual heating point, or abbreviated as ITP. It is designed to provide hot water supply, ventilation and heat to residential buildings, housing and communal services, as well as industrial complexes.

For its operation, it will require a connection to the water and heat system, as well as the electricity supply necessary to activate the circulation pumping equipment.

A small individual heating substation can be used in a single-family house or a small building connected directly to centralized network heat supply. Such equipment is designed for space heating and water heating.

A large individual heating station services large or multi-apartment buildings. Its power ranges from 50 kW to 2 MW.

Main goals

The individual heating point ensures the following tasks:

• Accounting for heat and coolant consumption.
• Protection of the heat supply system from emergency increases in coolant parameters.
• Disabling the heat consumption system.
• Uniform distribution of coolant throughout the heat consumption system.
• Adjustment and control of circulating fluid parameters.
• Converting the type of coolant.

Advantages

• High efficiency.
• Long-term operation of individual heating point showed that modern equipment this type, unlike other manual processes, consumes 30% less
• Operating costs are reduced by approximately 40-60%.
• Choice optimal mode heat consumption and precise adjustment will reduce thermal energy losses by up to 15%.
• Quiet operation.
• Compactness.
• The overall dimensions of modern heating units are directly related to the heat load. When placed compactly, an individual heating point with a load of up to 2 Gcal/hour occupies an area of ​​25-30 m2.
• Possibility of locating this device in small-sized basement rooms (both in existing and newly constructed buildings).
• The work process is fully automated.
• To service this thermal equipment, highly qualified personnel are not required.
• ITP (individual heating point) provides comfort in the room and guarantees effective energy saving.
• The ability to set the mode, focusing on the time of day, apply the weekend mode and holiday, as well as carrying out weather compensation.
• Individual production depending on customer requirements.

Thermal energy accounting

The basis of energy saving measures is the metering device. This accounting is required to perform calculations for the amount of thermal energy consumed between the heat supply company and the subscriber. Indeed, very often the calculated consumption is much higher than the actual one due to the fact that when calculating the load, heat energy suppliers overestimate their values, citing additional costs. Such situations will be avoided by installing metering devices.

Purpose of metering devices

• Ensuring fair financial settlements between consumers and energy suppliers.
• Documentation of heating system parameters such as pressure, temperature and coolant flow.
• Control over the rational use of the energy system.
• Monitoring the hydraulic and thermal operating conditions of the heat consumption and heat supply system.

Classic meter diagram

• Thermal energy meter.
• Pressure gauge.
• Thermometer.
• Thermal converter in the return and supply pipelines.
• Primary flow transducer.
• Magnetic mesh filter.

Service

• Connecting a reading device and then taking readings.
• Analyzing errors and finding out the reasons for their occurrence.
• Checking the integrity of seals.
• Analysis of results.
• Checking technological indicators, as well as comparing thermometer readings on the supply and return pipelines.
• Adding oil to the liners, cleaning the filters, checking the grounding contacts.
• Removing dirt and dust.
• Recommendations for correct operation internal heating networks.

Heating point diagram

The classic ITP scheme includes the following nodes:

• Input of the heating network.
• Metering device.
• Connecting the ventilation system.
• Connecting the heating system.
• Hot water connection.
• Coordination of pressures between heat consumption and heat supply systems.
• Recharge of heating and ventilation systems connected according to an independent circuit.

When developing a heating point project, the required components are:

• Metering device.
• Pressure matching.
• Input of the heating network.

The configuration with other components, as well as their number, is selected depending on the design solution.

Consumption systems

The standard layout of an individual heating point may have the following systems for providing thermal energy to consumers:

• Heating.
• Hot water supply.
• Heating and hot water supply.
• Heating and ventilation.

ITP for heating

ITP (individual heat point) - an independent scheme, with the installation of a plate heat exchanger, which is designed for 100% load. A dual pump is provided to compensate for pressure loss. The heating system is fed from the return pipeline of the heating networks.

This heating point can be additionally equipped with a hot water supply unit, a metering device, as well as other necessary blocks and components.

ITP for hot water supply

ITP (individual heating point) - an independent, parallel and single-stage circuit. The package includes two plate-type heat exchangers, each of which is designed to operate at 50% of the load. There is also a group of pumps designed to compensate for the decrease in pressure.

Additionally, the heating unit can be equipped with a heating system unit, a metering device and other necessary blocks and components.

ITP for heating and hot water supply

IN in this case The operation of an individual heating point (IHP) is organized according to an independent scheme. For the heating system, a plate heat exchanger is provided, which is designed for 100% load. The hot water supply scheme is independent, two-stage, with two plate-type heat exchangers. In order to compensate for the decrease in pressure level, a group of pumps is installed.

The heating system is recharged using appropriate pumping equipment from the return pipeline of the heating networks. The hot water supply is made up from the cold water supply system.

In addition, the ITP (individual heating point) is equipped with a metering device.

ITP for heating, hot water supply and ventilation

The heating installation is connected according to an independent circuit. For heating and ventilation system A plate heat exchanger is used, designed for 100% load. The hot water supply circuit is independent, parallel, single-stage, with two plate heat exchangers, each designed for 50% of the load. Compensation for the decrease in pressure level is carried out through a group of pumps.

The heating system is fed from the return pipeline of the heating networks. The hot water supply is made up from the cold water supply system.

Additionally, an individual heating point in an apartment building can be equipped with a metering device.

Principle of operation

The design of a heating point directly depends on the characteristics of the source supplying energy to the IHP, as well as on the characteristics of the consumers it serves. The most common type for this heating installation is a closed hot water supply system with a heating system connected via an independent circuit.

The operating principle of an individual heating point is as follows:

• Through the supply pipeline, the coolant enters the IHP, transfers heat to the heaters of the heating and hot water supply system, and also enters the ventilation system.
• The coolant is then directed into the return pipeline and returned through the main network for reuse at the heat generating enterprise.
• Some volume of coolant may be consumed by consumers. To replenish losses at the heat source, CHP plants and boiler houses have make-up systems that use the water treatment systems of these enterprises as a heat source.
• Entering thermal installation tap water flows through pump equipment cold water supply systems. Then some of its volume is delivered to consumers, the other is heated in the first stage hot water heater, after which it is sent to the hot water circulation circuit.
• Water in the circulation circuit moves in a circle through circulation pumping equipment for hot water supply from the heating point to consumers and back. At the same time, consumers withdraw water from the circuit as needed.
• As the fluid circulates along the circuit, it gradually releases its own heat. To maintain the coolant temperature at an optimal level, it is regularly heated in the second stage of the hot water heater.
• The heating system is also a closed loop through which the coolant moves with the help of circulation pumps from the heating point to consumers and back.
• During operation, coolant leaks may occur from the heating system circuit. The replenishment of losses is carried out by the ITP replenishment system, which uses primary heating network as a heat source.

Approval for operation

To prepare an individual heating point in a house for permission to operate, you must submit the following list of documents to Energonadzor:

• Active technical specifications for connection and a certificate of their implementation from the energy supply organization.
• Project documentation with all necessary approvals.
• An act of responsibility of the parties for operation and division of balance sheet, drawn up by the consumer and representatives of the energy supply organization.
• Certificate of readiness for permanent or temporary operation of the subscriber branch of the heating point.
• ITP passport with brief description heat supply systems.
• Certificate of readiness for operation of the thermal energy meter.
• A certificate confirming the conclusion of an agreement with an energy supply organization for heat supply.
• Certificate of acceptance of completed work (indicating the license number and date of issue) between the consumer and the installation organization.
• faces for safe operation and good condition of heating installations and heating networks.
• List of operational and operational-repair persons responsible for servicing heating networks and heating installations.
• A copy of the welder's certificate.
• Certificates for the electrodes and pipelines used.
• Acts for hidden work, as-built diagram of the heating point indicating the numbering of the fittings, as well as diagrams of pipelines and shut-off valves.
• Certificate for flushing and pressure testing of systems (heating networks, heating system and hot water supply system).
• Officials and safety regulations.
• Operating Instructions.
• Certificate of admission to operation of networks and installations.
• Logbook for recording instrumentation, issuing work permits, operational records, recording defects identified during inspection of installations and networks, testing knowledge, as well as briefings.
• Order from heating networks for connection.

Safety precautions and operation

The personnel servicing the heating point must have the appropriate qualifications, and responsible persons should also be familiarized with the operating rules that are specified in This is a mandatory principle for an individual heating point approved for operation.

It is prohibited to put pumping equipment into operation when the shut-off valves at the inlet are closed and when there is no water in the system.

During operation it is necessary:

• Monitor pressure readings on pressure gauges installed on the supply and return pipelines.
• Monitor the absence of extraneous noise and avoid excessive vibration.
• Monitor the heating of the electric motor.

Do not use excessive force when manually operating the valve, and do not disassemble the regulators if there is pressure in the system.

Before starting up the heating point, it is necessary to flush the heat consumption system and pipelines.

An individual heating point is designed to save heat and regulate supply parameters. This is a complex located in a separate room. Can be used in a private or apartment building. ITP (individual heating point), what it is, how it works and functions, let’s take a closer look.

ITP: tasks, functions, purpose

By definition, an IHP is a heating point that heats buildings completely or partially. The complex receives energy from the network (central heating station, central heating point or boiler house) and distributes it to consumers:

• DHW (hot water supply);
• heating;
• ventilation.

At the same time, it is possible to regulate, since the heating mode in the living room, basement, and warehouse is different. The ITP is assigned the following main tasks.

• Heat consumption accounting.
• Protection against accidents, control of parameters for safety.
• Disabling the consumption system.
• Even heat distribution.
• Adjustment of characteristics, control of temperature and other parameters.
• Coolant conversion.

To install ITP, buildings are modernized, which is not cheap, but brings benefits. The item is located in a separate technical or basement, an extension to the house or a separate building located nearby.

Benefits of having an ITP

Significant costs for the creation of an ITP are allowed in connection with the benefits that follow from the presence of a point in the building.

• Cost-effective (in terms of consumption - by 30%).
• Reduce operating costs by up to 60%.
• Heat consumption is controlled and taken into account.
• Optimization of modes reduces losses by up to 15%. The time of day, weekends, and weather are taken into account.
• Heat is distributed according to consumption conditions.
• Consumption can be adjusted.
• The type of coolant is subject to change if necessary.
• Low accident rate, high operational safety.
• Full automation of the process.
• Silence.
• Compactness, dependence of dimensions on load. The item can be placed in the basement.
• Maintenance of heating points does not require numerous personnel.
• Provides comfort.
• The equipment is completed to order.

Controlled heat consumption and the ability to influence performance are attractive in terms of savings and rational resource consumption. Therefore, it is believed that the costs are recouped within an acceptable period.

Types of TP

The difference between TPs is in the number and types of consumption systems. Features of the type of consumer predetermine the design and characteristics of the required equipment. The method of installation and placement of the complex in the room differs. The following types are distinguished.

• ITP for a single building or part thereof, located in the basement, technical room or nearby structure.
• Central heating center - the central heating center serves a group of buildings or objects. Located in one of the basements or a separate building.
• BTP - block heating point. Includes one or more units manufactured and supplied in a factory. It features compact installation and is used to save space. Can perform the function of ITP or TsTP.

Principle of operation

The design diagram depends on the energy source and specific consumption. The most popular is independent, for a closed hot water system. Principle ITP work next.

1. The heat carrier arrives at the point through a pipeline, giving the temperature to the heating, hot water and ventilation heaters.
2. The coolant goes into the return pipeline to the heat generating enterprise. Reusable, but some may be used by the consumer.
3. Heat losses are replenished by make-up available in thermal power plants and boiler houses (water treatment).
4. Tap water enters the heating installation, passing through a cold water pump. Part of it goes to the consumer, the rest is heated by the 1st stage heater, sent to the DHW circuit.
5. The DHW pump moves water in a circle, passing through the consumer's TP, and returns with partial flow.
6. The 2nd stage heater operates regularly when the liquid loses heat.

The coolant (in this case, water) moves along the circuit, which is facilitated by 2 circulation pumps. Its leaks are possible, which are replenished by replenishment from the primary heating network.

Schematic diagram

This or that ITP scheme has features that depend on the consumer. A central heat supplier is important. The most common option is a closed hot water system with independent connection heating. A heat carrier enters the TP through a pipeline, is sold when heating water for the systems, and is returned. For return there is a return pipeline going to the main line at central point— heat generation enterprise.

Heating and hot water supply are arranged in the form of circuits through which the coolant moves with the help of pumps. The first is usually designed as a closed cycle with possible leaks replenished from the primary network. And the second circuit is circular, equipped with pumps for hot water supply, supplying water to the consumer for consumption. When heat is lost, heating is carried out by the second heating stage.

ITP for different consumption purposes

Being equipped for heating, the IHP has an independent circuit in which a plate heat exchanger with 100% load is installed. Pressure loss is prevented by installing a double pump. Make-up is carried out from the return pipeline in the heating networks. Additionally, the TP is equipped with metering devices, a DHW unit if other necessary components are available.


ITP intended for hot water supply is independent circuit. In addition, it is parallel and single-stage, equipped with two plate heat exchangers loaded at 50%. There are pumps that compensate for the decrease in pressure, and metering devices. The presence of other nodes is assumed. Such heat points operate according to an independent scheme.

This is interesting! The principle of district heating for a heating system can be based on a plate heat exchanger with 100% load. And the DHW has a two-stage circuit with two similar devices, each loaded by 1/2. Pumps for various purposes compensate for the decreasing pressure and recharge the system from the pipeline.

For ventilation, a plate heat exchanger with 100% load is used. DHW is provided to two such devices loaded at 50%. Through the operation of several pumps, the pressure level is compensated and replenishment is provided. Addition - accounting device.

Installation steps

During installation, the TP of a building or facility undergoes a step-by-step procedure. Only one desire of the residents in apartment building not enough.

• Obtaining consent from the owners of premises in a residential building.
• Application to heat supply companies for design in specific house, development of technical specifications.
• Issuance of technical specifications.
• Inspection of a residential or other facility for the project, determining the presence and condition of equipment.
• The automatic TP will be designed, developed and approved.
• An agreement is concluded.
• The ITP project for a residential building or other facility is being implemented and tests are being carried out.

Attention! All stages can be completed in a couple of months. The responsibility is entrusted to the responsible specialized organization. To be successful, a company must be well established.

Operational safety

The automatic heating point is serviced by properly qualified workers. The staff is introduced to the rules. There are also prohibitions: the automation does not start if there is no water in the system, the pumps are not turned on if the input is closed shut-off valves.
Requires control:

• pressure parameters;
• noises;
• vibration level;
• engine heating.

The control valve must not be subjected to excessive force. If the system is under pressure, the regulators are not disassembled. Before starting, the pipelines are flushed.

Permission to use

The operation of AITP complexes (automated ITP) requires obtaining a permit, for which documentation is provided to Energonadzor. These are technical connection conditions and a certificate of their implementation. Needed:

• agreed upon design documentation;
• act of responsibility for operation, balance of ownership from the parties;
• act of readiness;
• heating points must have a passport with heat supply parameters;
• readiness of the thermal energy metering device - document;
• certificate of existence of an agreement with the energy company for the provision of heat supply;
• work acceptance certificate from the installation company;
• An order appointing someone responsible for the maintenance, serviceability, repair and safety of the ATP (automated heating point);
• list of persons responsible for maintenance of AITP installations and their repair;
• a copy of the welder’s qualification document, certificates for electrodes and pipes;
• acts on other actions, as-built diagram of an automated heating point facility, including pipelines, fittings;
• certificate for pressure testing, flushing of heating, hot water supply, which includes an automated point;
• briefing

An admission certificate is drawn up, logs are kept: operational, on instructions, issuance of work orders, detection of defects.

ITP of an apartment building

An automated individual heating point in a multi-storey residential building transports heat from central heating stations, boiler houses or combined heat and power plants (CHP) to heating, hot water supply and ventilation. Such innovations (automatic heating point) save up to 40% or more of thermal energy.

Attention! The system uses a source - the heating networks to which it is connected. The need for coordination with these organizations.

A lot of data is required to calculate modes, loads and savings results for payments in housing and communal services. Without this information, the project will not be completed. Without approval, the ITP will not issue permission to operate. Residents receive the following benefits.

• Greater accuracy of temperature maintenance devices.
• Heating is carried out with a calculation that includes the state of the outside air.
• The amounts for services on housing and communal services bills are being reduced.
• Automation simplifies facility maintenance.
• Reduced repair costs and personnel numbers.
• Finances are saved on the consumption of thermal energy from a centralized supplier (boiler houses, combined heat and power plants, central heating stations).

Bottom line: how the savings happen

The heating point of the heating system is equipped with a metering unit upon commissioning, which is a guarantee of savings. Heat consumption readings are taken from the devices. Accounting itself does not reduce costs. The source of savings is the possibility of changing modes and the absence of overestimation of indicators on the part of energy supply companies, their precise determination. It will be impossible to attribute additional costs, leakages, and expenses to such a consumer. Payback occurs within 5 months, as an average, with savings of up to 30%.

The supply of coolant from a centralized supplier - the heating main - is automated. Installation of a modern heating and ventilation unit allows you to take into account seasonal and daily temperature changes during operation. Correction mode is automatic. Heat consumption is reduced by 30% with a payback period of 2 to 5 years.

INSTRUCTIONS

Maintenance of central heating station (ITP) equipment

HOW TO USE THE INSTRUCTIONS

1. The instructions must be posted at the workplace.

2. The instructions are issued against signature to the operator of the heating point; the rest are required to sign on the control copy of the instructions.

3. A control copy of the instructions must be kept by the chief power engineer (mechanic) of the enterprise (organization, institution).

GENERAL PROVISIONS

1. The operator of the heating point on duty is responsible for each accident and for all damage or accidents that occur due to violation of rules and instructions.

2. The operator of the heating point directly carries out inspection, preparation for start-up of the equipment of the central heating point, maintenance and shutdown of the equipment. If necessary, involve other employees of the enterprise (organization).

3. The TsTP must contain the following documentation:

· thermomechanical equipment;

· electrical equipment;

· Instrumentation and A;

· distribution networks after the central heating substation with attached buildings and their characteristics;

b) Temperature graph;

c) Shift magazine.

4. PPR schedule.

5. Repair log.

6. This instruction, job description on TB and labor protection.

7. Automation operating instructions.

8. Operating instructions for automatic pump switching.

9. TsTP passport.

The TsTP should also have:

1. Table indicating those responsible for the operation of thermal and mechanical equipment, electrical equipment, instrumentation and automation equipment and their telephone numbers.

2. On entrance doors a plate with the number of the central heating station and an indication of its affiliation.

There must be a reserve in the central heating center operating materials: lubricant, stuffing box, paranit, etc.

The central heating center must be kept clean and tidy, both during operation and during repair work.

Admission of unauthorized persons to the central heating center is possible only with the permission of the management or persons responsible for the good condition and safe operation of the technical equipment and vehicles.

Basic technical data of the central heating station

Central heating point - central heating station is intended to supply heat to heating systems, supply ventilation systems, air conditioning and centralized hot water supply of objects connected to it.

The central heating station consists of volumetric elements-aggregates of factory production.

The thermomechanical part of the central heating station is assembled from the following units:

1. Unit thermal unit with hot water heater.

2. Water meter unit with booster (household) pumps.

3. Heating water heater unit with circulation pumps.

4. Heating booster pump unit.

5. Unit of circulation pumps for the hot water supply system.

The heat source for the central heating station is the __ district of the Moscow Heating Network Company OJSC with round-the-clock operation of heating networks at quality regulation. The coolant is superheated water with parameters 150 - 70°C.

The central heating station is equipped with repair lighting with a voltage of 36 V, water supply, sewerage, supply and exhaust ventilation, telephone.

Scheme of the central heating point

Connection of central heating stations to heating networks is carried out as follows:

Network water enters the annulus space II stages of a hot water supply water heater, and then into the heating system of buildings connected to heating networks according to a dependent scheme - through elevators. In a heating water heater, network water, passing through brass tubes, gives up its heat to the local water of the heating system passing in the interpipe space.

Water from the return pipelines of heating systems and from the water heater is then returned to external heating networks.

Tap water, passing through the pipes of the water supply water heater 1st stage, is heated by return water to approximately 30°C, then heated in the second stage to 60°C.

In the central heating station for the needs of hot water supply, a high-speed water heater with brass tubes with a diameter of 14-16, section length 4.0 m has been installed.

To avoid boiling of the heated water, it is planned to install automatic devices that shut off the supply network water when the temperature of the heated water rises above 60°C and turns on the supply of network water again when the temperature drops below 60°C.

To account for heat consumption, a heat meter of type ____________________ is provided. Primary coils with a diameter of ______ mm are installed on the forward and return pipelines of network water. A flow meter of type ____________, with a diameter of _____ mm, is installed on the heating system make-up line.

To account for water consumption for hot water supply, it is planned to install a hot water water meter of type ____________, with a diameter of ____ mm, on the water supply line going to the heater.

To circulate hot water in the hot water supply system, two pumps are installed (one backup).

To circulate local water from the heating system, two pumps (one backup) are installed with a power depending on the heat loss and capacity of the system.

Recharge independent system heating is carried out by make-up pumps (one backup).

The central heating substation has three water booster pumps with power and pressure, depending on the amount of water being disassembled and the number of storeys of the buildings. To avoid pressure increases in the local cold water supply system above 60 m.w.c., 2 “downstream” control valves are installed.

Thermomechanical part

1. The heating unit with hot water supply heaters includes:

a) steel head valves;

b) steel heating valves;

c) steel sectional valves that disconnect:

I 1st stage from the heating system;

IInd stage from the first stage;

1st stage from the heating system.

In addition, the unit is equipped with welding mudguards on the supply line and mudguards on the return line from the heating systems, pressure gauges, thermometric sleeves with thermometers, cork and 3-way brass taps, connecting impulse tubes, thermostat on the DHW line, automation type ____________________________________.

The correct functioning of the heating point equipment determines the economical use of both the heat supplied to the consumer and the coolant itself. The heating point is a legal boundary, which implies the need to equip it with a set of control and measuring instruments that make it possible to determine the mutual responsibility of the parties. The layout and equipment of heating points must be determined in accordance not only with the technical characteristics of local heat consumption systems, but also necessarily with the characteristics of the external heating network, the operating mode of it and the heat source.

Section 2 discusses connection schemes for all three main types of local systems. They were considered separately, i.e. it was believed that they were connected, as it were, to a common collector, the coolant pressure in which is constant and does not depend on the flow rate. The total coolant flow in the collector in this case is equal to the sum of the flow in the branches.

However, heating points are not connected to the heat source manifold, but to the heating network, and in this case, a change in coolant flow in one of the systems will inevitably affect the coolant flow in the other.

Fig.4.35. Coolant flow charts:

A - when connecting consumers directly to the heat source collector; b - when connecting consumers to the heating network

In Fig. 4.35 graphically shows the change in coolant flow rates in both cases: in the diagram in Fig. 4.35, A heating and hot water supply systems are connected to the heat source collectors separately, in the diagram in Fig. 4.35,b the same systems (and with the same calculated coolant flow) are connected to an external heating network that has significant pressure losses. If in the first case the total coolant flow increases synchronously with the flow for hot water supply (modes I, II, III), then in the second, although there is an increase in coolant consumption, at the same time the heating consumption automatically decreases, as a result of which the total coolant consumption (in in this example) is when applying the diagram in Fig. 4.35, b 80% of the flow rate when applying the scheme in Fig. 4.35, a. The degree of reduction in water consumption determines the ratio of available pressures: the greater the ratio, the greater the reduction in total consumption.

Trunk heating networks are designed for the average daily heat load, which significantly reduces their diameters and, consequently, the costs of funds and metal. When using increased water temperature schedules in networks, it is possible to further reduce the calculated water flow in the heating network and calculate its diameters only for the heating and supply ventilation load.

The maximum hot water supply can be covered using hot water accumulators or by using the storage capacity of heated buildings. Since the use of batteries inevitably causes additional capital and operating costs, their use is still limited. Nevertheless, in some cases, the use of large batteries in networks and at group heating points (GTS) can be effective.

When using the storage capacity of heated buildings, fluctuations in air temperature in rooms (apartments) occur. It is necessary that these fluctuations do not exceed the permissible limit, which can be, for example, +0.5°C. The temperature regime of premises is determined by a number of factors and is therefore difficult to calculate. The most reliable method in this case is the experimental method. In conditions middle zone RF long-term operation shows the possibility of using this method of maximum coverage for the vast majority of exploited residential buildings.

The actual use of the storage capacity of heated (mainly residential) buildings began with the appearance of the first hot water heaters in heating networks. Thus, the adjustment of the heating point with a parallel circuit for switching on hot water supply heaters (Fig. 4.36) was carried out in such a way that during the hours of maximum water withdrawal, some part of the network water was not supplied to the heating system. Heating points with open water supply operate on the same principle. For both open and closed heating systems, the greatest reduction in flow rate is heating system occurs at a supply water temperature of 70 °C (60 °C) and the lowest (zero) - at 150 °C.

Rice. 4.36. Diagram of a residential building heating point with parallel connection of a hot water supply heater:

1 - hot water heater; 2 - elevator; 3 4 - circulation pump; 5 - temperature regulator from the sensor outside temperature air

The possibility of organized and pre-calculated use of the storage capacity of residential buildings is implemented in the scheme of a heating point with a so-called pre-switched hot water supply heater (Fig. 4.37).

Rice. 4.37. Diagram of a heating point for a residential building with a pre-connected hot water heater:

1 - heater; 2 - elevator; 3 - water temperature regulator; 4 - flow regulator; 5 - circulation pump

The advantage of the pre-connected circuit is the ability to operate the heating point of a residential building (with heating schedule in the heating network) at a constant coolant flow throughout the heating season, which makes hydraulic mode The heating network is stable.

In the absence of automatic control at heating points, the stability of the hydraulic regime was a convincing argument in favor of using a two-stage sequential circuit for switching on hot water heaters. The possibilities of using this circuit (Fig. 4.38) compared to the pre-connected one increase due to covering a certain portion of the hot water supply load by using the heat of the return water. However, the use of this scheme is mainly associated with the introduction in heating networks of the so-called increased temperature schedule, with the help of which an approximate constancy of coolant flow rates at a heating point (for example, for a residential building) can be achieved.

Rice. 4.38. Diagram of a residential building heating point with two-stage sequential activation of hot water supply heaters:

1,2 - 3 - elevator; 4 - water temperature regulator; 5 - flow regulator; 6 - jumper for switching to a mixed circuit; 7 - circulation pump; 8 - mixing pump

Both in the circuit with a pre-heater, and in two-stage scheme with the sequential inclusion of heaters, there is a close connection between the release of heat for heating and hot water supply, with priority usually given to the second.

More universal in this regard is the two-stage mixed scheme(Fig. 4.39), which can be used both under normal and increased heating schedules and for all consumers, regardless of the ratio of hot water supply and heating loads. Mixing pumps are a mandatory element of both schemes.

Rice. 4.39. Diagram of a residential building heating point with two-stage mixed activation of hot water heaters:

1,2 - heaters of the first and second stages; 3 - elevator; 4 - water temperature regulator; 5 - circulation pump; 6 - mixing pump; 7 - temperature controller

The minimum temperature of the supplied water in a heating network with a mixed heat load is about 70 °C, which requires limiting the supply of heating fluid during periods of high outdoor temperatures. In the conditions of the central zone of the Russian Federation, these periods are quite long (up to 1000 hours or more) and the excessive consumption of heat for heating (relative to the annual one) because of this can reach up to 3% or more. Because modern systems heating systems are quite sensitive to changes in temperature-hydraulic conditions, then in order to avoid excessive heat consumption and maintain normal sanitary conditions in heated rooms, it is necessary to supplement all the mentioned heating point schemes with devices for regulating the temperature of water entering the heating system by installing a mixing pump, which is usually used in group heating points. In local heating points, in the absence of silent pumps, an elevator with adjustable nozzle. It should be taken into account that such a solution is unacceptable with a two-stage sequential circuit. There is no need to install mixing pumps when connecting heating systems through heaters, since their role in this case is played by circulation pumps, ensuring constant water flow in the heating network.

When designing heating point circuits in residential neighborhoods with a closed heat supply system, the main issue is the choice of connection scheme for hot water heaters. The chosen scheme determines estimated costs coolant, control mode, etc.

The choice of connection scheme is primarily determined by the accepted temperature regime of the heating network. When a heating network operates according to a heating schedule, the choice of connection scheme should be made on the basis of a technical and economic calculation - by comparing parallel and mixed schemes.

A mixed scheme can provide a lower temperature of the return water as a whole from a heating point compared to a parallel scheme, which, in addition to reducing the estimated water consumption for the heating network, ensures more economical electricity generation at the CHP plant. Based on this, in design practice for heat supply from thermal power plants (as well as in the joint operation of boiler houses with thermal power plants), preference is given to a mixed scheme for the heating temperature schedule. With short heating networks from boiler houses (and therefore relatively cheap), the results of the technical and economic comparison may be different, i.e. in favor of using a simpler scheme.

With an elevated temperature schedule in closed systems heat supply connection scheme can be mixed or sequential two-stage.

A comparison made by various organizations using examples of automation of central heating points shows that both schemes, under conditions of normal operation of the heat supply source, are approximately equally economical.

A small advantage of the sequential scheme is the ability to operate without a mixing pump for 75% of the duration of the heating season, which previously gave some justification for abandoning pumps; with a mixed circuit, the pump must operate all season.

The advantage of a mixed circuit is the ability to completely automatically turn off heating systems, which cannot be achieved in a sequential circuit, since water from the second stage heater enters the heating system. Both of these circumstances are not decisive. An important indicator of schemes is their performance in critical situations.

Such situations may be a decrease in water temperature in a thermal power plant against the schedule (for example, due to a temporary lack of fuel) or damage to one of the sections of the main heating network in the presence of redundant jumpers.

In the first case, the circuits can react approximately the same, in the second - differently. There is a possibility of 100% consumer reservation up to t = –15 °C without increasing the diameters of heating mains and jumpers between them. To do this, when the supply of coolant to the thermal power plant is reduced, the temperature of the supplied water simultaneously increases accordingly. Automated mixed circuits (with the mandatory presence of mixing pumps) will respond to this by reducing the consumption of network water, which will ensure the restoration of normal hydraulic conditions throughout the entire network. Such compensation of one parameter by another is useful in other cases, since it allows, within certain limits, to carry out, for example, renovation work on heating mains in heating season, as well as localize known discrepancies in the temperature of the supplied water to consumers located at different distances from the thermal power plant.

If the automation of regulation of circuits with sequential switching on of hot water supply heaters provides for a constant flow of coolant from the heating network, the possibility of compensating the coolant flow by its temperature in this case is excluded. There is no need to prove the feasibility (in design, installation and especially in operation) of using a uniform connection scheme. From this point of view, a two-stage mixed scheme has an undoubted advantage, which can be used regardless of the temperature schedule in the heating network and the ratio of hot water supply and heating loads.

Rice. 4.40. Diagram of a heating point for a residential building open system heating supply:

1 - water temperature regulator (mixer); 2 - elevator; 3 - check valve; 4 - throttle washer

Connection diagrams for residential buildings with an open heat supply system are much simpler than those described (Fig. 4.40). Economical and reliable operation of such points can be ensured only if an automatic water temperature regulator is available and operates reliably; manual switching of consumers to the supply or return lines does not provide the required water temperature. In addition, the hot water supply system, connected to the supply line and disconnected from the return line, operates under the pressure of the supply heat pipe. The above considerations regarding the choice of heating point schemes apply equally to both local heating points (MTP) in buildings and to group ones, which can provide heat supply to entire microdistricts.

The greater the power of the heat source and the radius of action of the heating networks, the fundamentally more complex MTP schemes should become, since absolute pressures increase, the hydraulic regime becomes more complex, and transport delays begin to affect them. Thus, in MTP schemes there is a need to use pumps, protective equipment and complex automatic control equipment. All this not only increases the cost of construction of MTPs, but also complicates their maintenance. The most rational way to simplify MTP schemes is the construction of group heating points (in the form of GTP), in which additional complex equipment and instruments should be located. This method is most applicable in residential neighborhoods in which the characteristics of heating and hot water supply systems and, therefore, MTP schemes are of the same type.

When it comes to the rational use of thermal energy, everyone immediately remembers the crisis and the incredible fat bills it provoked. In new buildings, where engineering solutions are provided to regulate the consumption of thermal energy in each individual apartment, you can find best option heating or hot water supply (DHW), which suits the tenant. For older buildings, the situation is much more complicated. Individual heating points are becoming the only reasonable solution to the problem of saving heat for their inhabitants.

Definition of ITP - individual heating point

According to the textbook definition, an ITP is nothing more than a heating point designed to serve an entire building or its individual parts. This dry formulation requires clarification.

The functions of an individual heating point are to redistribute energy coming from the network (central heating point or boiler room) between ventilation, hot water supply and heating systems, in accordance with the needs of the building. In this case, the specifics of the premises being served are taken into account. Residential, warehouse, basement and other types of them, of course, must differ in temperature conditions and ventilation parameters.

Installation of ITP implies the presence separate room. Most often, equipment is installed in basements or technical rooms high-rise buildings, extensions to apartment buildings or in detached buildings located in close proximity.

Modernizing a building by installing ITP requires significant financial costs. Despite this, the relevance of its implementation is dictated by the advantages that promise undoubted benefits, namely:

• coolant flow and its parameters are subject to accounting and operational control;
• distribution of coolant throughout the system depending on heat consumption conditions;
• regulation of coolant flow in accordance with emerging requirements;
• possibility of changing the type of coolant;
• increased level of safety in case of accidents and others.

The ability to influence the process of coolant consumption and its energy performance is attractive in itself, not to mention the savings from the rational use of thermal resources. One-time costs for ITP equipment will more than pay for itself in a very modest period of time.

The structure of the ITP depends on what consumption systems it serves. In general, its package may include systems for providing heating, hot water, heating and hot water, as well as heating, hot water and ventilation. Therefore, the ITP necessarily includes the following devices:

1. heat exchangers for transferring thermal energy;
2. shut-off and control valves;
3. instruments for monitoring and measuring parameters;
4. pump equipment;
5. control panels and controllers.

Here are only the devices present on all ITPs, although each specific option may have additional nodes. The source of cold water supply is usually located in the same room, for example.

The heating point circuit is built using a plate heat exchanger and is completely independent. To maintain the pressure at the required level, a double pump is installed. There is a simple way to “replenish” the circuit with a hot water supply system and other components and assemblies, including metering devices.

The operation of IHP for DHW implies the inclusion in the circuit of plate heat exchangers operating only for the DHW load. In this case, pressure drops are compensated by a group of pumps.

In the case of organizing systems for heating and hot water supply, the above schemes are combined. Plate heating heat exchangers operate together with a two-stage DHW circuit, and the heating system is fed from the return pipeline of the heating network through appropriate pumps. The cold water supply network is the feeding source for the hot water supply system.

If it is necessary to connect a ventilation system to the ITP, then it is equipped with another plate heat exchanger associated with it. Heating and hot water supply continue to operate according to the previously described principle, and the ventilation circuit is connected in the same way as the heating circuit with the addition of the necessary control and measuring instruments.

Individual heating point. Principle of operation

The central heating point, which is the source of the coolant, supplies hot water to the entrance of an individual heating point through a pipeline. Moreover, this liquid in no way gets into any of the building systems. Both for heating and for heating water in DHW system, as well as ventilation, only the temperature of the supplied coolant is used. Energy transfer to the systems occurs in plate-type heat exchangers.

The temperature is transferred by the main coolant to water taken from the cold water supply system. So, the cycle of movement of the coolant begins in the heat exchanger, passes through the path of the corresponding system, giving off heat, and returns through the return main water supply to further use to the enterprise providing heat supply (boiler house). The heat transfer part of the cycle warms homes and makes the water in taps hot.

Cold water enters the heaters from the cold water supply system. For this, a system of pumps is used to maintain the required level of pressure in the systems. Pumps and additional devices are necessary to reduce or increase the water pressure from the supply line to an acceptable level, as well as to stabilize it in building systems.

Advantages of using ITP

The four-pipe heat supply system from a central heating point, which was used quite often in the past, has a lot of disadvantages that ITP does not have. In addition, the latter has a number of very significant advantages over its competitor, namely:

• efficiency due to a significant (up to 30%) reduction in heat consumption;
• the availability of devices simplifies control over both coolant consumption and quantitative indicators of thermal energy;
• the ability to flexibly and quickly influence heat consumption by optimizing its consumption mode, depending on the weather, for example;
• ease of installation and rather modest overall dimensions of the device, allowing it to be placed in small rooms;
• reliability and stability of ITP operation, as well as a beneficial effect on the same characteristics of the serviced systems.

This list can be continued as long as desired. It reflects only the basic, superficial benefits obtained by using ITP. You can add to it, for example, the ability to automate ITP management. In this case, its economic and operational indicators become even more attractive to the consumer.

Most significant disadvantage ITP, not counting transportation costs and costs for loading and unloading activities, is the need to settle all kinds of formalities. Obtaining the appropriate permits and approvals can be considered a very serious task.

In fact, only a specialized organization can solve such problems.

Stages of installing a heating point

It is clear that one decision, even a collective one, based on the opinion of all residents of the house, is not enough. Briefly the procedure for equipping the facility, apartment building, for example, can be described as follows:

1. in fact, a positive decision of the residents;
2. application to the heat supply organization for the development of technical specifications;
3. obtaining technical specifications;
4. pre-design inspection of the facility to determine the condition and composition of existing equipment;
5. development of the project with its subsequent approval;
6. conclusion of an agreement;
7. project implementation and commissioning tests.

The algorithm may seem quite complicated at first glance. In fact, all the work, from decision to commissioning, can be done in less than two months. All worries should be placed on the shoulders of a responsible company that specializes in providing this type of service and has a positive reputation. Fortunately, there are plenty of them now. All that remains is to wait for the result.