How to choose a gas meter: guidelines for choosing a device for a private house and apartment
The price of energy resources is steadily increasing and is not going to decline in the foreseeable future. The efficient owner tries to use them as efficiently as possible. Metering devices will help him in this. They should be installed in all private houses, and according to innovations in the legislation, and in apartments.
We will tell you how to choose a gas meter, introduce you to models of devices used in domestic conditions. Here you will learn by what criteria you should choose a flow meter that records the supply of main gas to the consumer. Based on our recommendations, you can choose the best model and the place to install it.
The content of the article:
- Why do I need a gas meter?
- Types of metering devices
- Criteria for choosing the optimal counter
- Conclusions and useful video on the topic
Why do I need a gas meter?
Some consumers of gas in the old manner pay for it according to the standards, motivating this by the fact that the cost of the meter with installation is prohibitive.
Indeed, they have such a right, but economically it is very disadvantageous. Why is this happening?
Firstly, the board is initially overpriced. It is calculated by the maximum gas consumption, which in real life is extremely rare, or even not at all.
Payment according to the standards takes into account the maximum of all possible options for gas consumption by everyone living in an apartment or house. If there are two, three, or even more tenants, the sums obtained are not small.
In addition, the state is interested in the fact that the consumed resources are recorded by metering devices, therefore, the current legislation provides for increasing coefficients that increase the gas payment according to the standards. Over the course of several years, this coefficient gradually increases until it reaches a maximum.
Whereas installation of the meter involves payment only for the actually consumed amount of gas. Practice shows that it differs significantly from that calculated by standards. Accordingly, the board is significantly reduced.
The real difference in payment allows you to quickly pay back the purchase price and installation of the meter, and subsequently receive significant benefits from this.
For those who have autonomous gas heating, installing a meter provides another advantage. They can use their heating equipment regardless of the start or end of the heating season.
Consumers who do not have metering devices are automatically disconnected from the gas supply after the end of the heating season until its beginning. Counter setting solves this problem.
Before contacting gas workers with an application for installation and sealing of a gas flow meter, you must select and buy a device. And this is not easy, because there are now an impressive number of them on the market. According to the principle of operation, all gas consumption meters are divided into the following groups:
Types of metering devices
Gas metering equipment is diverse. There are several types of such devices that differ in the principle of operation. Let's consider each in more detail.
Option # 1 - Rotary or Rotary
It is a chamber metering device with eight-shaped rotors that are used as converting elements.
Structurally, the device consists of a housing, counting and transmission mechanisms. Inside the casing are two identical-sized rotating rotors in the shape of a figure eight. One of them is connected to the transmission and counting mechanisms.
The casing is equipped with an inlet or top and outlet or bottom nozzle for gas. When the latter begins to enter the body, a pressure difference occurs, which causes the rotors to rotate.
They do this synchronously, for which the gears fixed in the end boxes are responsible. During rotation, the rotors touch each other with their side surfaces, which is necessary for the counting process.
The volume of gas that is displaced by one rotor in half its revolution is equal to the volume corresponding to the amount of gas bounded by the inside of the housing and the surface of the rotor in a vertical position. For each complete revolution of two rotors four such volumes are forced out of the housing. Accordingly, the flow rate through the gas meter is easily taken into account.
The advantages of such devices include a significant measurement range and high throughput. Moreover, they are quite compact.
In addition, the devices are durable, non-volatile, not sensitive to short-term overloads. The level of noise they produce is considered average, it is almost imperceptible. Of the shortcomings, it is worth noting the short verification period. He is only 5 years old.
Option # 2 - diaphragm or membrane
It is a chamber-type counter used to account for small gas flows. The body of the device is divided into two parts. At the top are the gas inlet and outlet pipes.
Both fragments of the body are securely fastened together. Between them, special gaskets are installed and paste-like sealant is placed. Also inside the case is a diaphragm measuring mechanism.
It consists of two chambers resembling blacksmith furs. Each of these chambers is connected via levers and cranks to a common valve spool mechanism. Gas supply channels pass through it.
The number of cameras can be different, the accuracy and class of the measuring device depends on their number. The spool mechanism by means of a shaft is connected to a counting device fixed to the housing.
When gas enters the device, it is alternately displaced from the bellows. This leads to alternate movement of the diaphragm walls. As soon as one chamber is filled, the spool mechanism switches and it starts to release gas.
This cycle is repeated many times. It is accompanied by the movement of the diaphragms. This movement launches a counting mechanism that takes into account the amount of gas that has left the chamber for a certain unit of time.
Membrane counters are distinguished by high measurement accuracy. Simplicity of design gives them a significant operational resource, which is at least 20 years. Such devices are extremely easy to maintain and economical.
However, if necessary, masking the membrane counter is very difficult. Another disadvantage is the rather high cost of equipment. The verification period for diaphragm-type devices is 10 years.
Option # 3 - Turbine Meter
The device got its name because of the presence of a small turbine in it, the wheel of which rotates under the pressure of the gas flow entering the device.
Structurally, the equipment is a fragment of a pipe equipped with flanges.The following mechanisms are placed sequentially in the device case, starting from the inlet pipe: a jet rectifier and a turbine proper with rotation bearings and a shaft.
For smooth operation of the bearings, lubrication is necessary, therefore, a pump assembly is mounted on the meter housing. With its help, oil is supplied to the rotating elements through special tubes.
The principle of operation of the measuring device is quite simple. The number of revolutions of a rotating turbine by means of a reduction gear is transmitted to a special counting mechanism fixed outside the gas cavity.
Turbine meters can be equipped with additional detectors for measuring pulses, temperature or pressure. In addition, the measurement process can have three degrees of automation. The lack of automation assumes that the user independently reads the instrument.
Semi-automatic measurements suggest that the control is performed by a computing device, but manual correction of indicators, settings, etc. is possible. Full automation of the measurements assumes that the readings of the measuring device arrive at the computing device, which processes them and transmits them to the metering center.
The advantages of turbine meters are non-volatility, reliable design and ease of maintenance. The device can work with gas of not the highest degree of purification. The noise level emitted by the device can be characterized as low. Manufacturers produce turbine meters in a large number of sizes.
The disadvantages of the equipment should include measurement errors. If the device operates continuously, the error is minimal, if in pulsed mode, the measurement distortion increases significantly. Verification period is 8 years.
You can check the main gas meter without removing the device from its original location. How such testing is performed is described in detail in featured article.
In order to get the most accurate meter readings that take into account gas consumption, devices are now being produced that focus on a specific type of consumer:
Criteria for choosing the optimal counter
Having become acquainted with various types of gas meters, you can decide which one to choose for your home. However, in addition to the type of device, there are several important parameters that must be considered when choosing. We will consider each of them one by one.
Throughput should be understood as the maximum amount of gas mixture that equipment can measure per unit of time. Usually this is one hour of work. This value must be compared with the maximum gas consumption in the house or apartment.
To do this, you need to calculate the total gas flow.To do this, add up the average consumption of all devices using it.
It will be much easier to do this if you find the technical documentation for each device and take the desired value from there. The manufacturer must indicate in the equipment certificate the maximum gas volume consumed.
The total consumption is calculated for all gas appliances located in the apartment, even if some of them, according to the owner, is used extremely rarely.
Moreover, if you plan to purchase and install additional gas equipment, its consumption also needs to be added to the total. Then you will not have to buy and install a new counter later.
Determining the maximum gas flow, you need to choose a flowmeter with a throughput greater than the obtained value. It will be very simple to do this, if you read the label of the device correctly. It is a letter G, near which there are numbers.
So, a meter labeled G1.6 has a throughput of 1.6-2.5 cubic meters per hour, G2.5, respectively, can pass 2.5-4 cubic meters per hour, G4 - from 4 to 6 cubic meters, G6 - from 6 to 10 and G10 - from 10 to 16 cubic meters. m per hour. Based on this marking, a suitable measuring device is selected.
Instrument Design Features
A variety of installation sites for gas meters determines their design features. The first thing you need to pay attention to is the direction of gas movement. It can be served left or right.
Depending on this, the devices are divided into left and right. It is necessary to clearly present the connection diagram of the meter, since it is physically impossible to install left-hand equipment on the right side and vice versa.
The direction of gas movement must be indicated by an arrow on the instrument body. It must be strictly observed.
Another important point is the diameter of the thread of the connecting pipe of the device. It must exactly match the size of the pipe through which the gas is supplied, and on which the meter will be installed. For apartment buildings, the pipe diameter is standard and ½ inch.
In buildings erected on an individual project, these sizes can vary. Most often, supply pipes with a diameter of ½, ¾ or 1 inch are found. Depending on the diameter of the thread, cap nuts are selected for mounting the device. They must exactly match the installation dimensions.
It is also important that the interaxal distances of the threaded joints coincide, they also are different. For top-mounted devices mounted on a horizontal pipe, this distance varies from 110 to 250 mm.
High throughput devices that are installed where the number of consumers is more than two can have an interaxial distance of more than 250 mm.
The presence or absence of a temperature corrector
A standard gas meter can operate in the temperature range from -40 to +40 ° C. However, the correctness of the measurements made by him under such conditions may raise doubts.
This is due to the fact that the gas mixture tends to expand or contract when the temperature rises and falls. The role and pressure in the system plays. Therefore, it is possible to talk about the correct operation of the measuring device only under normal pressure and temperature of 20 ° C.
It is clear that such conditions do not always exist. Especially if the gas meter is installed on the street, which is not prohibited by law. In the cold season, gas services can suffer serious losses, since the actual volume of gas consumed increases, and its consumption by the meter remains practically unchanged.
In the hot season, economic losses are already borne by consumers who have to pay for increased gas consumption, although the actual volume of gas supplied has not changed. To avoid this, a special device called a thermal corrector is used. It does not allow changes in temperature and pressure to affect gas consumption.
Thus, in any conditions, the measurements made by the meter are the most correct. You need to know that gas meters equipped with a temperature corrector cost much more than standard ones. Therefore, they should be installed only where complex operating conditions are expected.
For example, in the kitchen of a city apartment, where a stable comfortable temperature is maintained, this device will be clearly superfluous. While the installation of such equipment on the street is justified and necessary.
The importance of the date of manufacture
The current federal law regulates the regular verification of metering devices. Moreover, the first of them is carried out at the factory immediately after the release of the product. Information about it is entered in the technical passport of the device.
Thus, it turns out that the date of the next periodic verification is counted from the date indicated in the documents. Therefore, when buying a new device, you need to carefully study the technical documentation and clarify the date of the first verification.
It happens that the device "stays" in the warehouse and goes on sale in two, three, or even five years from the date of manufacture. Therefore, its calibration interval is automatically reduced by this period. And it turns out that the recently installed meter is already subject to verification or replacement. This can be an extremely unpleasant surprise for an inattentive owner.
The contract concluded with the gas service must indicate the date of the first calibration of the measuring device. Gas workers closely monitor the timing of verification, but they are not required to inform users about them.
Therefore, if a consumer, due to inattention, lack of knowledge, or for any other reason, misses the deadline for checking his flow meter, he will be issued an invoice calculated according to the standards.
The calibration interval for gas meters of different types is significantly different. But in any case, it is less than the life of the device.
For verification, the equipment is dismantled and sent to a specialized workshop, where specialists will check it and issue a conclusion on the possibility of further use.If the device is deemed fit for use, a special mark must be made in its technical passport.
You can choose a gas meter in your apartment or house yourself, but it is better to entrust this responsible business to specialists from the gas service. They will competently analyze the operating conditions of the device and offer models of devices suitable for a particular apartment.
However, if you want to do everything yourself, when choosing a device, you should consider the following significant points:
- The maximum amount of gas consumed by residents. It depends on the required bandwidth of the model. It is calculated taking into account all operating gas appliances.
- The location of the meter. You must choose immediately to determine the design features of the meter.
- Noise level equipment. It is advisable to purchase the least noisy model.
- Intertesting interval. The longer it is, the better.
- Service life and reliability of the model.
Important Notice. For an apartment, you should not buy a meter with a temperature corrector, no matter how hard sellers try to advertise it. This is a waste of money.
Actually, the choice of a gas meter for a private house is practically no different from the choice of a device for an apartment. But there is a slight nuance. Building codes stipulate the installation of gas meters not on the premises, but on the street.
The owner of gasified private property should know about the rules for the location of the meter regarding equipment and structures:
Many owners of private homes, connected to the main gasdo just that. They set the counter on the street. In this case, you should choose only equipment with a temperature corrector, otherwise there may be problems with paying for gas.
In addition, care must be taken to protect the equipment case, otherwise adverse weather conditions will quickly disable the meter. The easiest way is to purchase a special installation cabinet similar to box for automatic machines. It is convenient for use and the device is placed safely for itself.
Conclusions and useful video on the topic
Video # 1. How the membrane gas meter works and works:
Video # 2. How to choose a gas meter:
Video # 3. Gas meters for home and apartment:
A gas meter is required in every home. It helps to maximize the use of energy and, ultimately, significantly save money from the family budget. In order for the device to work correctly and for a long time, it is important to choose it as competently as possible.
Do not completely trust the sales consultants who are interested in selling their product. It is better to carefully study the technical documentation and make an informed choice on your own.
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