Air Conditioning Relay Unit With Heat-Medium Start-Up Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In multi-air conditioning systems for buildings, the circulation of refrigerant can lead to leaks and inefficient energy use due to long circulation paths, complex constructions, and reduced heat-exchanging performance with non-azeotropic refrigerant mixtures, resulting in prolonged wait times for cooling or heating operations and compromised user comfort.
Innovation Solution
An air-conditioning apparatus with a relay unit that exchanges heat between refrigerant and a heat medium, using two pipes for refrigerant and two pipes for heat medium transport, allowing for efficient energy transfer and reduced energy consumption by minimizing the length of the heat medium circulation path and simplifying construction, while supporting both cooling and heating operations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If refrigerant is circulated directly to indoor units, then cooling or heating can be provided, but refrigerant may leak into rooms and safety is compromised
Solution Approach 1:
The patent introduces a heat medium (water or antifreeze) as an intermediary substance that carries thermal energy between the outdoor heat source device and indoor units. This heat medium circulates through dedicated pipes rather than using refrigerant, thereby eliminating the safety hazard of refrigerant leakage into occupied spaces while maintaining the heat transfer function. The heat medium acts as a safe mediator that decouples the refrigerant circulation system from the indoor environment.
2Reliability
If heat medium is used to transport heat, then safety is improved, but the circulation path becomes longer and transport power consumption increases
Solution Approach 1:
The patent segments the heat transfer system into two distinct circulation loops: a refrigerant circulation loop confined to the outdoor heat source device, and a heat medium circulation loop that serves both outdoor and indoor units. This segmentation allows the heat medium to be transported only to locations where heat exchange is needed, rather than circulating refrigerant through entire building spaces. The segmented approach optimizes the heat medium circulation path length and reduces unnecessary transport power consumption.
3Adaptability or versatility
If four pipes are connected for cooling and heating selection, then operational flexibility is improved, but construction complexity increases
Solution Approach 1:
The patent implements a universal two-pipe system where the same pair of pipes (supply and return) is used for both cooling and heating operations. By incorporating a four-way valve in the outdoor heat source device, the system can reversibly switch the direction of heat medium flow through the same physical infrastructure. This multi-functional approach eliminates the need for separate four-pipe installations for cooling and heating, thereby reducing construction complexity while maintaining full operational flexibility.
4Productivity
If refrigerant is used for heat transfer, then heat-exchanging performance is maintained, but wait time for operation activation increases with non-azeotropic refrigerant mixtures
Solution Approach 1:
The patent changes the physical parameter of the heat transfer medium from refrigerant (which requires phase change and has temperature glide issues with non-azeotropic mixtures) to liquid heat medium (water or antifreeze). This parameter change eliminates the temperature glide phenomenon during heat exchange, allowing for more efficient and faster thermal energy transfer. The liquid heat medium can be rapidly heated or cooled in the outdoor heat source device and quickly delivered to indoor units, reducing wait time for operation activation while maintaining or improving heat-exchanging performance.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration reduces wait times for cooling and heating operations, enhances user comfort by providing efficient energy transfer, and simplifies construction, thereby addressing the inefficiencies and complexities of existing systems.
Implementation Method 1
a relay unit 2 that exchanges heat between the refrigerant and the heat medium
Data Source
Figure 1
Figure 2
Figure 3
AI summary
When starting a cooling operation mode from a non-operating mode, the blower device of the indoor unit from which the start command is originated is operated. When starting a heating operation mode from a non-operating mode, the blower device of the indoor unit from which the start command is originated is operated after the heat medium temperature becomes equal to or greater than a preconfigured temperature.