Nowadays payment for consumed heat is often the most expensive item of expenditure budget.But out of this situation is: you need to buy a heat meter, which is a separate measuring device or set of devices intended for metering heat and mass determination and characteristics of the coolant in the system with water heat supply.When properly installed heat meter heating bills will be much lower (25-50% depending on the features of the building in which it is installed).
- The principle of heat meters
- Types of heat meters
- Features installation of residential heat meters
- Heat on the market measuring instruments
The principle of heat meters
Any heat meter consists of the following elements:
- calculator amount of thermal energy.
- Power supplies pressure and flow (if necessary).
- primary flow converters.
- Gauge pressure (customized).
With the help of such a device is determined by a large number of parameters, including:
- time period of the devices that are installed on a particular node records.
- average daily and hourly temperature of the coolant in the pipes of cold water needed to feed, as well as flow and return type.
- consumption amount of heat energy: how to aggregate and for each hour.
- volume coolant inlet and outlet of the heating system of a building or a separate apartment.
- volume of coolant that is consumed by a constant feeding system.
Heat needed for the registration of the amount of heat, which used data collected from members of the temperature sensor device and water flow.The total amount of thermal energy that is consumed heating system per hour is calculated as the product of the temperature difference between the coolant inlet and outlet of the water flow and it in the same time period.It defines the value of the special computer, which comes and information flow and temperature difference.For their supply meet the flow sensors and two temperature sensors, one of which is mounted in the supply line of water supply system, and the other in the back.The calculator handles information provided by, and gives the exact value of the consumed quantity of heat, which is displayed on the LCD screen or is removed by a conventional optical interface.Deviation determined error of measurement of the temperature difference in quality instruments does not exceed 3-6%.
Types of heat meters
Today before installing the heat meter is worth understanding the basic varieties.By the principle of operation, these devices heat records are divided into the following types:
- electromagnetic heat meters.They are based on the phenomenon of the electric excitation current to the fluid being cooled under the influence of a magnetic field.That is, electromagnetic induction occurs that links above average speed, and hence the volumetric flow of coolant, the field strength in it and the difference of potentials appearing at the electrodes of opposite charge.Since the determination of the amount of heat is dependent on the measurement of very small quantities of current, electromagnetic counters require special operating conditions and quality of installation.Indication error increases significantly when an additional resistance in the joints, bad connection of wires and the presence of iron compounds in the water and other impurities.However, metrological verification of such devices typically exhibit a good result.
- mechanical heat meters will be pleased with the simplicity of the consumer.They translational motion coolant flow is converted into a rotary movement of the measuring element of the device for determining the amount of heat energy.These models consist of a rotary vane or water meters and mechanical type of calculator.They're an affordable price, but to increase their useful life must be in front of them to install special filters.In addition, it is not recommended to use mechanical heat meters in systems where the coolant is water with high rigidity.Small particles of rust and scale stuck in filters and other parts of the device, disabling it.Also, these flow meters are responsible for a rather significant reduction in water pressure compared with other types of heat meters.
- ultrasonic heat meters, for which the price will be slightly higher than in the other models, determine the amount of heat consumed by changing the time period for which the ultrasound passes from the source of the signal to its receiver.This option depends on the speed of the fluid flowing in the heating system.When installing such a metering device and the receiver of the ultrasonic signal transmitter mounted on the tube opposite each other.The emitter emits a signal which passes through the water and reach the receiver.The time during which this occurs is directly related to the rate of flow in the pipe, so its value for precisely determine the flow rate.Ultrasonic heat meters show a good result only in the case of pure water flowing through the pipes completely devoid of rust.If used as a coolant liquid containing a scale, sand, scale, and its consumption is not stable, the readings of such devices are considered accurate only with great reserve.A feature of such devices is the ability to regulate fluid flow into two separate channels.
- Vortex heat meters operated by the well-known physical phenomenon is the formation of vortices behind an obstacle in the path of flow.It is composed of a pipe is installed permanent magnet, a triangular prism, a vertically built in in the pipe, and the measuring electrode, also in the pipeline, but a little further in the direction of flow of the coolant.Wrapping liquid prism leads to a pulsating pressure variations flow that allows us to determine the amount of fluid flowing through the pipes of the system.The frequency of vortex shedding is directly proportional to the speed of the flow inside the pipeline.At the vortex heat meters have significant advantages.They are influenced by a sharp change in the rate of coolant and foreign matter in it large, but the lime deposits on the surface of pipes or a high concentration of iron in the water can not affect the operation of the measuring device.The quality of the measurement does not affect the fact whether the vortex heat meter is installed in horizontal or vertical section of the system.
on how to use such distinguished heat meters:
- obschedomovyh heat meters, which are usually set at the entrance to the multi-storey houses, and occasionally in the workplace.Such devices are suitable without problem for pipelines with a diameter of 32 to 150 mm, and some models are designed for a diameter of 300 mm.
- Heat meters for individual apartments.They are mounted at the entrance to the heating system of an apartment or private cottage.Such models are used for pipes of 15-20 mm in diameter and consisted of two elements.This Calculator, which is equipped with two sensors which record the water temperature in the feed and in the exhaust pipe from the apartment and hot water meters, through which heat meters apartment able to determine not only the amount of heat, but also to record the amount of water coming into your home.
- distributors of heating costs.This electronic device to determine the relative proportion of the apartments in the common house heat flow, which is determined by the collective (general building) energy meter.The principle of its action is based on the difference in temperature radiator in the room and the room temperature is constantly recorded over time.The distributor of heating costs is mounted directly on the surface of the radiator and does not require intervention in the district heating system.
Features installation of residential heat meters
If you decide to reduce the amount of the bill for the consumed heat and the installation of heat meters is becoming a reality, it is not necessary to apply to the specialized organizations.It is enough to get a package of permits for installation, prepare the device itself accounting of heat, connecting set with check valve, filter, collets, special cranes, equipped with sensors of heat, heat-conductive paste, a wrench for metal pipes or welding for composition of the heating system.After that, you must do the following:
- Rinse the pipeline, which will be the installation of heat meters.This will prevent clogging and reduce uncertainty in calculations of the device.This should ensure that a flow of the unit contained water, and the direction of the arrow on the body corresponds to the direction of water flow.Installing modern models available on the vertical and horizontal sections of the pipeline system.
- Before installing the measuring unit, make sure that the system has no pressure and coolant.Then proceed to the installation of ball valves with the temperature sensor before and after the heat meter.They make it possible not only to determine a temperature difference, but also instantly block the pipe in case of emergency.Observe care when you turn on the system unit for measuring heat meters: since it is located in the flow part, it is very easy to damage.
- The kit includes two thermocouple devices, one of which is mounted in a measuring cartridge and the other - in the pocket, treating its special heat-conducting paste.Properly installed teplopreobrazovatel should block the tube by two-thirds.Then, these elements are subject to sealing.
Heat on the market measuring instruments
Now installation of the heat meter becomes really important.But the range of devices on the market is very large, so consider the features of several popular models:
- Heat Elf.These devices make it possible to remotely read information and to connect additional devices, equipped with pulse outputs (for example, gas and water meters).But they relate to the mechanical type, and means sensitive to impurities in the coolant, and must be replaced after 4-5 years.Their cost ranges between 160-190 dollars.
- Heat CT-10.Designed to accommodate not only the heat, but also electricity, as well as the volume of consumption of hot and cold water.The device is able to work with both electromagnetic and mechanical water meters.However, not all models of the series has a built-in controller.The prices for these start at $ 250.
- Heat ENKONT (RF) can handle up to four lines and take into account the heat exchange in two independent circuits.It refers to an ultrasonic type, so the accuracy of his statements greatly affects water pollution in pipes.Such a device will cost depending on the complexity of dollars in 1500-3200.
- Heat Magica (RF).The device is classified as electromagnetic devices, supplemented by a digital interface allows you to connect several flow meters and thermocouples.Also, it requires very good quality installation and costs from $ 600.
the best choice in terms of quality of work and the price can be called a device for recording heat ST-10.