Purchase of meters.
First of all, the counters for hot and cold water have different design elements, although the function is performed the same - count cubic meters of flow. The hot water meter( it has a red strip along the body diameter) can be installed as a cold water meter, however such devices are much more expensive. A "cold" counter( it has a blue belt along the body) can not be used to calculate the cost of hot water, such installation will not even be made in Gorvodokanal. Instruments for measuring the amount of water are of two types:
- mechanical;
- electronic.
Electronic gauges, of course, are very presentable, but chips often fail, which means extra money and bureaucratic wire. Do you want it? The best option in the purchase of the device are reliable turbine counters with an impeller. Each device for monitoring and accounting of consumed water must necessarily have a quality certificate and it must be demanded when purchasing a new device. Also, make sure that the device includes the following components:
- check valve for each product;
- strainer;
- connection nuts and gaskets.
Often you can see on sale only the counter itself, without accessories, and this is not correct. Pay special attention to the presence and integrity of the seal, which means that this device has passed the obligatory test and is suitable for further operation. 
Variety of water meters.
- single-jet water meter-under the influence of pressure water, the impeller rotates and counts the number of these revolutions. That is, the amount of fluid that filled the space is directly proportional to the number of circular motions of the blades.
- multi-jet water meter - there is a division of water under the influence of the wings in the mechanism on several different jets.
- turbine water meters - suitable for both cold and hot water. The quantity of cubic meters is considered by means of rotation of the turbine.
For the accuracy of manufacturing, they are divided into meters installed vertically - class A, and class B - meters mounted in a horizontal position. 
Important recommendations of
Another important element in the purchase of a new water meter in St. Petersburg is the presence of a passport for the product printed in the printer, rather than a scanned copy. The serial number on the product and indicated on the technical passport must match and the manufacturer's stamp must be stamped. The water meter, which does not have documentation, is also subject to mandatory verification, but it will have to pay for it.
And a few technical recommendations:
- if there is a fire drain, then it is installed a valve on which the Lenvodokanal should put a seal;
- water meters should be located in rooms, the temperature of which does not fall below +5 ºС.There are no problems with flats and apartment houses, but it is necessary to look for a solution for meters installed in the basements of St. Petersburg and its region.
The installation of meters for water has become mandatory for all categories of citizens. Many companies are engaged in assembling and processing all necessary documents in St. Petersburg and this is not a problem. 
