Engineering overview

• Project Name: Dexinyuan Hot Spring Hotel
• Project address: Hebei Province
• Total construction area: 10000 ㎡.
• House type: Residential building with swimming hall
• Heating use area: 9000㎡ 
• wall body: Steel structure and brick-concrete structure 
• Refrigeration Area: 9000㎡ 
• Heat source equipment: ultra-low temperature air source heat pump 
• Indoor system equipment: horizontal concealed fan coil units 
• Functional requirements: cooling in summer and heating in winter

Design ideas

The hot spring hotel is divided into dining area, swimming hot spring area, hotel area, which is open 24 hours a day. The horizontal concealed fan coil units in each room can independently adjust and control the temperature according to individual needs; The space height of swimming hot spring area is 11 meters, and the space is large, which requires high comfort, so the required air volume is large; The dining area is only open at a fixed meal time, and each district has different requirements for central air-conditioning system, so it needs to operate independently to meet the cooling and heating requirements of different districts. In addition, according to the adjustment of national energy policy and the requirements for environmental protection, using clean, energy-saving and efficient new energy is the main policy of the country for a long time in the future. Therefore, engineers independently match the air-conditioning system scheme for each district, which is distributed by each district. The heat source is air source heat pump, and the end is horizontal concealed fan coil units and ceiling units. Each district is controlled independently without affecting each other, which can fully meet the refrigeration and heating needs of each district.

In this scheme, electric power is used as the clean energy source for cooling and heating. By consuming a small amount of electric energy, the low-grade heat energy in the atmosphere is converted to high-grade heat energy, and the ultra-low temperature air source heat pump unit is used to prepare cold water and hot water for cooling and heating of buildings. The utilization of this new energy can completely replace the municipal central heating and any heating methods such as coal, fuel, gas and electric heating, and can also refrigerate in summer, which greatly reduces the investment, and can still run normally and efficiently in the ultra-low temperature environment of -25℃ without auxiliary electric heating. The system has strong stability, high reliability, good heating effect, environmental protection and no pollution, and no special person is needed to manage it. Under the normal working condition of fan coil unit (cooling device), the indoor temperature reaches or exceeds the standard specified in Hebei Province’s Measures for Heating.

Calculation parameters

Form 1 Calculation parameters of outdoor design in summer in Hebei Province

Form 1 Calculation parameters of outdoor design in winter in Hebei Province

Colding and heating load calculation

According to the Design Manual of Heating, Ventilation and Air Conditioning, the cooling and heating heat loads are composed of basic cooling/heat consumption and additional cooling/heat consumption of outer envelope and inner envelope and cold air infiltration cooling/heat consumption. According to outdoor temperature parameters in Hebei, the unit cooling load index is designed to be 120W/㎡, the unit heat load index is 80W/㎡ in hotel area and 150/㎡ in swimming hot spring area. Considering the use habit of summer refrigeration in this project, the comprehensive utilization rate is 80%, which can reduce the investment cost. Each room can independently control the temperature according to the use situation, and the use is more flexible. The operating cost is independently calculated, and there is a large space for saving the operating cost.

Determination of cooling load

   Q1=9000×120×80%=864kw

According to the characteristics of buildings and climatic conditions, the rated refrigerating capacity of ultra-low temperature air source heat pump should be ≥864kw to meet the use requirements

Determination of heating load

  Q2=5000×80+4000×140=960kw

According to the characteristics of buildings and climatic conditions, the output heat of ultra-low temperature air source heat pump with average minimum temperature of -7℃ should be ≥960kw to meet the use requirements.

System Principle

Air-source heat pump absorbs a large amount of low-temperature heat energy in the air through very little electric energy, which is compressed by the compressor and changed into high-temperature heat energy, and the water is transferred to heat the water. The hot water is used for heating through the fan coil, and can provide summer refrigeration.

Environmental protection and energy saving

The power of heating is free air heat energy, which only needs to consume a little power when absorbing air heat energy, and the thermal efficiency is as high as 270%-430%. Compared with traditional energy sources, it not only has high thermal efficiency, but also avoids the pollutant emission caused by the use of chemical energy, thus achieving the dual effects of energy conservation and environmental protection. Indoor rooms are cooled and heated by fan coil units, which operate independently and automatically adjust the temperature, making the operation more stable and energy-saving.

Safe and reliable

By adopting physical working method, no toxic gas will be produced during the whole heating process, and no leakage accident will occur during the separation of water and electricity.

cold operation

Not affected by the environment, it can be used all the year round. Whether in rainy days or cold winter, the intelligent control of heat pump unit can save manpower investment and ensure all-weather synthesis of high-temperature heat source.