How to calculate the data of central air conditioning during the renovation of commercial buildings?

There are three calculation methods: time type, accurate energy type and time energy type.

Time-based billing method for central air conditioning

Charging principle: Connect the three-speed switch of the fan coil and the power supply of the electric two-way valve to the current collector. When the collector detects the data of two-way valve and wind speed signal, it uploads it to the computer monitoring system for analysis and processing, accumulates the state time of each gear, converts it into reference time through the given coefficient, and charges according to the approved price.

Advantages: time parameters are easy to measure, easy to manage and calculate, and various operations can be performed on the terminal regularly or in real time.

(1) Solve the problem of heating fee payment for residents in unfavorable positions of buildings (top floor and terminal units). Because the heat is distributed according to the product of heating area and accumulated time, the top and end units will be equipped with more radiators according to the design, so there is no need to share more heat costs.

(2) The installation is convenient, economical and reliable. The integrated intelligent device of heating control and heat distribution metering has less stringent requirements on water quality than heat meters and temperature control valves, and less stringent requirements on radiator types and installation conditions than heat distribution meters. Suitable for various terminal heating systems, with simple structure, convenient installation and high reliability.

(3) It integrates adjustment and metering, with less equipment and low cost, which avoids the disadvantages of complicated reconstruction of the traditional heat metering air conditioning system, a large number of temperature control valves and heat distribution meters and high cost, and is convenient for sharing the heat of users.

In domestic air conditioning metering, most of them are office buildings and office buildings, and these buildings are mostly fan coil units and fresh air systems. Fan coil unit plus fresh air system is a semi-centralized central air conditioning system. When there are many air-conditioned rooms and each room needs independent adjustment, it is more suitable to adopt the time equivalent air-conditioning billing system.

Disadvantages: The changes of chilled water flow, cooling capacity and temperature are not considered, which deviates from the principle of "whoever pays, pays as much as he uses", making customers unwilling to save energy.

Scope of application: suitable for office buildings, senior apartments, senior living quarters, hotels, independent shops, etc.

Accurate energy type central air condition charging method

Charging principle: Install matching high-precision temperature sensors in the inlet and return pipe, and install electromagnetic flowmeter in the return pipe. The flow rate of chilled water is measured by flowmeter, and the energy loss is calculated by the temperature difference between inlet and outlet water. Meanwhile, the temperature signal and the flow signal are connected to the energy integrator. The monitoring system accurately charges according to the energy integrator.

Advantages: Through the instantaneous changes of flow and temperature, the calculation is accurate, the method is transparent and more easily accepted by users. Realize the principle of "whoever uses pays and pays as much as he uses".

Disadvantages: However, the system is complex, the equipment cost is high, and the sensor anti-interference technology needs to be improved.

Time-energy central air-conditioning charging method

It is mainly suitable for comprehensive buildings with the above two charging requirements.

system profiler

The scope of application of the time and energy comprehensive charging method: a comprehensive building that charges by households and floors (or large areas) at the same time.

System characteristics

1. Meet the needs of independent billing in large and small areas at the same time;

2. Diversified functions, with multiple functions of central air conditioning billing system based on time and energy.

Charging mode

Comprehensive pricing method:

1. Determine the energy unit price first, and then determine the time unit price.

2. There are two types of energy: distribution method and fixed unit price method.

3. Time-based reference "two-part" pricing method.