【 Weak current College 】 household air-conditioning system design elementary

1 Introduction

From 2000 to 2010-10 years, China's average annual residential building, of which 10 million m2 of construction area of urban housing 2.5 million to 3 million m2. Sales in Shanghai in 2001, for example, the new residential 17 million m2, second-hand market trading 1480 million m2, about 55 million users by 50%, air-conditioning consumption meter, 22.5 million sets, a huge market space. Experts predict that, with the improvement of living standards, the development of housing construction, central air conditioner the miniaturization, the commercial, home air conditioning will be the future of air conditioning.

2 household characteristics of central air conditioning with

A) has the advantage of a single room air conditioner. If the quality is reliable, low failure rate, use a flexible, easy installation, easy maintenance, etc.

B) have a central air conditioner's strengths, such as room temperature distribution, do not occupy the room area, and better cope with decoration, indoor and low noise.

C) has better personalized to reflect in the household personal purchases, personal use, on the other hand arrangement of indoor air conditioners can be flexible, depending on the room layout, personal preferences there are several options to choose from.

D) domestic central air-conditioning consumption groups not only for high consumer groups, and mainly against ordinary wage-earners. As the air conditioning manufacturers to mass production, development, its price will gradually decline, so that household air-conditioning can settle for ordinary people families.

3 several household central analysis and comparison of air conditioning

3.1 community central cooling heating supply system

Centrally located in the community and heat source station, outdoor network will be hot and cold water to each household. The system has the advantage of the central air-conditioning, such as room temperature distribution, do not occupy the room area, indoor and low noise. But one-time investment, you need effective property management, usually running costs, billing accurate measurement difficulties, use the original planned economy. With the abolition of welfare, housing subsidies, centralized supply of privatization of housing and heating system of billing, charging more and more difficult, this system also shrinking market share.

3.2 household small air-cooled heat pump air conditioning system

By air-source heat pump unit, indoor unit and air conditioning pipes and accessories. Outdoor unit located on the terrace, the outdoor noise barrier. Air-cooled heat pump units built-in small pressure expansion tank, circulating pumps and automatic water valve. Fan-coil air conditioning Terminal comes in many forms, depending on the owners preferences, features used, interior decoration, etc.

The system of compact structure, convenient in installation, and full air system is less than the total building space, easy to tie in with the decor. Unit is equipped with built-in expansion water tank allows the installation, operation, maintenance and more simple and non-destructive beauty of architectural appearance. Air source heat pump unit adopts microcomputer automatic control, easy to operate, each room independent control, and centralized control, convenience and practical, easy-to-electricity-saving. If fresh air needed to set up a new unit, increasing the cost.

The shortcomings of the system are: catchment tray easy dust, bacteria, leakage vulnerability exists, but easily finds leak, ease of maintenance. Air source heat pump unit for three-phase power supply, additional distribution, electricity metering etc.

3.3 multi-split air conditioner system (often known as household frequency conversion air conditioning system)

The indoor and outdoor machine, refrigerant pipes, condensed water pipes. Same with 3.2 programmes, outdoor unit is placed on the terrace, indoor variety to choose from, but between indoor and outdoor machine adopts copper pipe connection, refrigerant without circulation pump and expansion tank,. Optional single phase electric current, without organising three households, saves the lines for metering and billing.

The system advantages: as refrigerant direct evaporation, energy efficiency is high; have all household air-conditioning performance, such as: ion dust filters, Photocatalyst, luminous remote control, low noise, etc. Indoor air automatic swing, vanes; model specifications, options, according to different properties, select the functional requirements; a drag more than one, according to the number you are running indoor unit and each room a different load conditions, frequency circuit adjustment compressor speed to adapt each time the amount of the total charge, so that each has indoor machine efficiency, compared with traditional air conditioning energy saving 40%, reduce operating costs, energy saving and economy; outdoor machine compact, convenient and flexible installation, saving outdoor space, beautify the home environment, reduce the number of outdoor machine; with automatic failure detection, easy maintenance; automatically convert heating/cooling mode, automatic wind transform, timing, night setting mode, you can simultaneously realize centralized management and separate control.

The drawback: the supply peak differential, power generators in low load run-time efficiency, greater energy consumption; greenhouse gas emissions greatly increases; no fresh air supply, installation requirements; in the event of a refrigerant pipe leak, it is difficult to find leak, it is difficult to maintain, its higher price. At present, domestic air-conditioning Haier, beauty and the promotion of such models, prices are expected to be further reduced.

Drag a wind 3.4 tube air conditioning system

The outdoor unit, ducted air conditioning tank, air supply and air valve, air outlet. Refrigeration principle is similar with split air conditioning, a direct evaporative refrigerant, simply 3.3 Festival programmes, indoor unit change in the air handling unit for pipe type. The pipeline is an all-air conditioning-box system, no water system and its ancillary equipment, significantly reducing the initial investment; indoor unit is placed in the interior ceiling, saving room area and investment in infrastructure; the wind system is simple, without hand management, simply check regularly, and 3.2 Festival programmes concern than no leakage, relative prices low; can take full account of the fresh air, improve indoor air quality, keep the air clean; direct evaporative cooling air, obviate the chilled water cycle due to energy loss and evaporation temperature relative to water chillers, thus increasing the efficiency of refrigeration systems.

Ducted air conditioning tank outlet, wind pressure is high, usually 80 ~ 150Pa, available through the duct to guarantee each outlet of cold and hot air has some range, make roomAirflow and temperature field remain evenly; or you can configure the muffler, fully meet the requirements of the indoor noise. In place of large air-conditioned malls using multiple pipeline machine, which narrows the indoor load changes, start stop part pipe machine for energy regulation; but used in residential air conditioning, room cannot be independently controlled use, centralized air, affecting the privacy of a room; wind pipes accounted for a large architectural space. In addition to poor air filter, air enthalpy drop small, dehumidifying capacity is not strong.

More than four residential central air conditioning methods that each has its own characteristic way, depending on the project, a comparative analysis of economic, technical, and determine the final best for air conditioning. But at present, the author believes multi-split air conditioning system and a drag-and-a wind pipe air conditioning system is more suitable for now house air conditioning. The former causes due to price, promotion up there is a certain difficulties, it is estimated that over the next few years, with a large number of household air-conditioning manufacturers, involved in commercial air conditioning price decline in market share will continue to rise; the latter should now have good market potential.

4 in domestic central air-conditioning system design and construction of

4.1 air-conditioner can be just the right amount of zoom

Press in most people's lifestyle, home, quickly open air conditioning, and hope to reach air conditioning effects; the other due to the non-insulated enclosure structure, not the upper, lower neighbours, air conditioner, cold loss due to enlarge the capacity of the air-conditioner, guarantees that the air conditioning effect. At the indoor unit is equipped with the adjusting device, you can adjust the volume, the cooling capacity.

4.2 outdoor host capacity may be appropriate to reduce the

By now most of the families of three or five family lifestyle, air-conditioning end cannot simultaneously full-load operation, when the living room, dining room air conditioner, bedroom, study room and almost no or less open. Visual concrete circumstances, reduce host capacity, reducing the initial investment and operating costs.

Quality assurance 4.3 installs

Pipe installation should be strict, air leakage, water leakage cannot, in particular, refrigerant pipe leak, it is difficult to find the leak, maintenance difficulties, but also easy to produce. Air conditioning pipes, refrigerant pipes may consider wearing beams, walls, etc., to save space

4.4 condensate discharge, pipe insulation to do

Water is households often encounter problems, decoration is more difficult to solve. On the air conditioning system, the condensate discharge most overlooked potential leakage risks arising. Condensation water yishe independent vertical tube set emission, horizontal pipe should not be too long, and make not less than 0.008 slope vertical tube. Air pipe, air-conditioning condensation water in particular pipes and refrigerant pipes, because the temperature is low, such as thermal insulation, exterior condensation dripping water easily.

5 conclusion

Residential central air conditioning industry in China is a very new industry, since the reform and opening up later evolved, after more than ten years of efforts to establish a higher level of the enterprise, has led the domestic central air-conditioning industry to take off, I believe that in the next few years, with the rapid progress of science and technology, the market further specification, household central air-conditioning industry will enter a new era.

Reference documents:

[1] GBJ-87, heating ventilation and air conditioning design specification [S]

[2] luyao Kyung, etc. Practical heating and air-conditioning Design Manual [M]. Beijing: the Chinese construction industry press, 1993.

[3] Gu Hing Ying, etc. Civil building HVAC design technical measures [M]. Beijing: the Chinese construction industry press, 1996.

Photographer: Ambrose China Jiangxi building design Research Institute, Jiangxi Nanchang 330046

Liu Hua (1964-), male, Bachelor, senior engineer, Chief Engineer.