【 Weak current College 】 commercial building energy-saving strategies of central air conditioner selection---Power By 【 China power house network 】

Commercial building, power consumption statistics air conditioning electricity accounted for 40% or more, so how to choose the correct use of air conditioning equipment, air-conditioning system and do maintenance work, is today an important topic of saving energy. (A) how to choose a central air conditioning system 1. Please choose the high energy efficiency ratio of air-conditioning cooling EER, host Government Notice minimum standards of the EER value. 2. choose the higher the EER value host in cold water, the more energy saving chillers, in General, EER values, each improving 0.1 can save 4% chillers using electricity. Chiller of capacity per hour can be removed from the Interior heat that 1 frozen tons per hour from 3 indoor heat removal, 024kcal (equivalent 12,000 BTU), according to this projection, per square metre room about 0.15 refrigeration tonnes (equivalent to 450kcal/h), selection of air conditioning refrigeration ton capacity is too large, will make the compressor running long light, or frequent start, power consumption, and derogating from the compressor life. Note:
1. the chiller energy efficiency ratio (EER) kcal/h-W = cooling capacity (kcal/h) divided by the test of cooling consumption required power (W), 2. the coefficient of performance (COP) = cooling capacity (W)/consumption electric power (W) = 1.163EER. 1 RT (refrigeration ton) = 3, 024kcal/h. (Ii) how to install a central air conditioning system 1. chiller should be placed in the concrete foundation, plate or base, leverage and bolted and keep the level to cement flat supplement. Cold water host should be left around the appropriate maintenance space, so that future pumping heat exchanger or cleaning copper tube, and other maintenance work. 2. the pump should be installed gauges and export pipeline to better understand the actual operating conditions. 3. cooling towers around should be well ventilated, must not be blocked, so as not to affect the cooling capacity. Avoid installing theheat, so as not to affect the cooling towers of cooling effect. 4. small cooler installed, water plate must maintain a certain degree of inclination for condensate drain; air conditioning tank air duct on the air outlet shall adjust the allocation of appropriate, so as to avoid a regional air flow shortage. Outlet and return air outlet not too close, so as to avoid the short-cycle influence the effect of cold room. 5. pipe diameter 65mm following ' use of threaded connections, use the above 80mm welded or flange connection. Drain each meter shall maintain 1 cm of tilt. Cold water pipes high point or other the necessary, should be installed with an automatic discharge valve; hoses should be loaded low point drain valve for system cleaning.

6. air duct in the differences, the differences should be equipment with a view to adjusting air door and lock. Air tube and return air pipe should be thermal insulation, thermal insulation materials should conform to national standards specifications. (Iii) how to operate the central air conditioning system 1. air temperature setting range with 26-28 ° c, suitable, and automatic temperature control equipment should be installed so as to avoid the waste of energy supercooled. For regular access to the rooms, the indoor temperature not lower than the outdoor temperature 5 ° c above, so as not to affect their health. 2. daily scheduled record cold water temperature of the host (s) are running, oil pressure, temperature, pressure, temperature, refrigerant pressure refrigerant, current and voltage, in order to understand the real situation. 3. without prejudice to refrigeration, moderately improve chilled water outlet temperature, improve the cold water outlet temperature of 1 ° c, about the power consumption can be reduced by 2% water host. 4. should reduce the cooling water temperature setting, each lower cooling water temperature 1 ° c, could save the power consumption of cold water host 2%. 5. in the first half hour off from work, use cold water and cooling water circulation pump to continue operating. 6. the night to a small number of units to work overtime, you should partition only the supply of air conditioning, additional space to save energy. 7. cooling system if they belong to the water separation system, and air conditioners use 2-way valve to control the amount of cold water, the pump can be equipped with inverter and number control systems to conserve energy. 8. underground car park of exhaust air to an additional controller, in non-vehicular peak times setting hourly running for about 15 minutes to conserve energy. 9. air conditioning use period closed Windows and doors to prevent cold energy leaking or hot air infiltration, air box back to the Tuyere Department not to pile up incidentals, so as not to affect air quality. (Iv) how the maintenance of the central air-conditioning system

1. water-cooled condenser copper tube is vulnerable to the effects of poor water quality, production scale, at least one must be clean. 2. refrigeration oil oil color black or impurities, you should replace it immediately. 3. compressor Motors annually recurring implementation of insulation testing. 4. keep refrigerant quantity is normal, if any, should the leak after filling. 5. regularly check the water pump bearings, and Tim note lubricants, water pump shaft seal Department if there is leakage phenomenon, should fix; import and export pressure gauge damage, should be replaced. 6. cooling towers to clean once a month. 7. always check the cooling tower water, floating ball switch and sprinkler heads correctly. 8. the cooling towers in a outlet of protection network who has fallen off, you should immediately install, so as to avoid significant loss of cooling water and debris falling into the impact of cooling. 9. small cooler and air handling unit of the filter should be cleaned regularly every month, and monthly check transmission belt tight and control system is working properly. 10.motor should be periodic maintenance (lubrication), reduces the friction loss of the motor. (V) the efficiency of central air conditioning system, central air conditioning system efficiency in addition to choosing high EER value or high COP value of cold water to host regardless of water systems, air systems and energy-saving control to do the effectiveness of energy saving, briefly described as follows: 1. the pump head and flow rate must be compatible with the host of freezing cold tonnage, each frozen tonnage of cooling water needed is 13 lpm (liter per minute), cold water volume is 10 lpm and use 70% efficiency pump and high-efficiency motors. 2. air handling unit system fan, 1, 000L/s air power consumption should be below 1.7kW. 3. cooling towers tonnage to cold water host tonnage of 1.25 times. You can use multiple parallel combination products, combined with temperature control, turn on the operating table. 4. Select the appropriate capacity of motor, General load rate 75 ~ 100% maximum efficiency. 5. air conditioning Division and controlRegard, each space or air conditioning use similar (for example: temperature and air-time) of multiple space groups, should be set temperature sensor for automatic temperature control, as follows: (1). the auto-stop: can be used by the personnel of sensors, you can program using the program controller for air conditioning or manual of timer for automatic shutdown. (2) independent air conditioning area: each independent air conditioning area provide automatic shutdown or control air conditioning, fresh air and exhaust of independent control unit. Each independent air conditioning is not greater than 2 region, 000m2 air-conditioned floor area and a floor. (3) confined parking blower: air is greater than 14, 000L/s, you can design according to the parking space of carbon monoxide concentration (ppm) value, a fan and stopping control or adjust the ventilation rate, while at the same time when parking lot controller uses strengthdecreases, the fan will stop functioning or adjust the ventilation rates. (Vi) air conditioning system and energy-saving design 1. comprehensive province can design: basically, the comprehensiveness of the province can design should include at least five part of energy saving measures, as follows: (1). the application of energy-saving green building daily. (2). choosing high efficiency air conditioning equipment. (3). the rational design of the air-conditioning system for energy consumption. (4). the management practices of saving air conditioning energy consumption. (5). the correct maintenance of the system in the State of the most energy-efficient. 2. air conditioning load: a building, the air conditioning load characteristics as follows: (1). the Office hours and number of the more fixed, easy to estimate air conditioning load. (2). the night overtime should avoid air-conditioning full open for use supplied to the minority. (3). the least part of the 24-hour operations space, such as room, computer room, etc., should be independent of air conditioning more energy saving effect. (4); General personnel density design reference values for the space of 7 to 19m2, take the intermediate value is 13m2/person, room personnel density up to each person 2m2. (5). the peripheral zone (from within the exterior 5m) of air conditioning load changes is large, air-conditioned design appropriate capacity control you want to avoid the sometimes too cold and uncomfortable and waste energy. 3. air conditioning system and energy-saving control design: (1)-Vav (VAV) design to some load controller save energy, to control the wind tube static pressure and airflow fan speed, suitable for static pressure set point at about one-third of the total design of static pressure (a downstream service), when the air is the design of air volume, 50% less power consumption design blower power consumption by 30%. (2). the air conditioning pump system should be designed to variable flow (VWV) control, flow control to the original design flow of 50% or below. In 50% of design capacity, shall have control and device (for example to change the motor speed motor inverter), so that the water pump power consumption not more than 30% of the total load. Variable flow control or equipment required to control with flow requirements or minimum differential pressure control, differential pressure measurement point is located in the most remote of heat exchangers or heat exchanger maximum differential pressure requirements. Contains more than one chiller air conditioning cold water system, when the part number chiller is closed, the reduction must be relatively cold water flow to save sent water consumption. (VII) system testing and acceptance considerations for air conditioning system in the completion of performance testing should be conducted, the respective amount of wind and water adjusted to balance the system to the design point, except for design features, more energy-efficient operation of the effect, following some notes for this: 1. the system of acceptance of documents: the system acceptance should have actually installed an illustration of the construction documents, on the record should include each device location and performance data, wind pipes and plumbing system of General plane configurations, including size and Terminal air or design of water flow. Except that the operation and maintenance manual for at least contain the following: (1). each device requires maintenance of the data on the device and select accessories. (2). each device shall require operation and maintenance manuals, and the need for routine maintenance tomorrow. (3). at least one maintenance agent's name and address. (4). the air-conditioning control system maintenance and calibration information, contains the route map, schematic description of the control order, set point, and so on, need a permanent record in the control device of control charts or digital control system is designedin a comment. (5). the future for each system and suggestions for how to set up a complete narrative of. 2. the system balance test; (1). the air conditioning system completion acceptance is required in accordance with the relevant standards for measurement, balance and adjust the air flow and air duct flow and design values of the differences of less than 10%. (2). the balance of air system, the need to first open the door to minimize the damage, then in addition to the variable flow distribution system of adjusting device does not need to balance out (for example, calibrate the VAV terminal box), and the remaining are to be adjusted to the design of flow value. (3). the water system of balance required to first open the throttle to minimize losses, then finished with a water pump impeller or adjust the pump speed to design flow. Each system should have measured the pump function of the differential pressure or the water pump on each side were left to test.