The features of the VRF system that can be considered at first glance can be listed as advantages and disadvantages below:
Advantages and Disadvantages of Vrf System
Advantages
• No need for a separate mechanical room in the building
• The size of the outdoor unit is smaller than alternative systems (chiller, etc.)
• Transport and assembly convenience of outdoor units as they consist of modules
• Ease of sharing operating expenses compared to central systems
• High energy efficiency (COP and EER values) and low operating costs
• Up to 40% energy savings can be achieved in projects where thermal loads are very variable during the day, such as hotels and hospitals.
• No need to store fuel
• Long economic life of the system
• Reduction in land and construction costs
• Independent control of the areas
• The indoor unit models used in the system have more than 10 model options and their locations can be easily changed later compared to aqueous systems
• Ability to connect different types of indoor units to the same line
• Easy capacity increase
• Since the coils in the indoor units are smaller than the fan-coil system indoor units, and therefore the fans are smaller, the indoor units can operate more silently.
• Ability to heat and cool at the same time through zoning and heat recovery
• Ease of connecting to all kinds of automation (advanced central control options)
• Environmental features (low CO2 emission and in compliance with the Kyoto protocol)
• Pipe cross-sections are much smaller due to the fact that R407C and R410A refrigerants have more heat carrying ability than water
• Providing flexibility and speed in seasonal transitions as the refrigerant can be controlled more rapidly
• A better distribution of heating and cooling by means of remotely adjustable culvert blades of the indoor units
• Precise control of the room temperature (+-0.5 C) by means of electronic expansion valves
• No need for expert technical staff for operation • No need for backup
• Easy and fast workmanship and installation of copper pipes used in the system
• Ease of maintenance
• Temperature control in the rooms, authorization, programming for energy saving, reporting, specifying the location of the fault, calculating the energy cost of each location, weekly operating programs etc. can be made through the Building Management System.
• Compressors can be operated sequentially on an equal distribution basis in equal time
• In case of failure of one of the compressors in the outdoor unit, only the failed compressor can be disabled and the system can continue to operate.
• Likewise, the failure of one of the indoor units does not affect the others
disadvantages
• Limited fresh air facilities and the need for additional systems
• Relatively high initial investment value
• Special team required for service
• The need for drainage (especially in ceiling types) may be a problem.
• High cost of refrigerant flux
• Hot or cold blowing from one point may adversely affect comfort in places
• The need to consider additional ventilation systems when humidification is required (primary air)
• Limited dehumidification
• Standard and limited types of indoor unit filters
• Sound in indoor units according to the selected brand
• Problems may arise in very hot or very cold regions if good design is not done.
• It may be necessary to increase the fan speed in order to bring the hot air down in heating mode in ceiling type units (the sound will also increase)
• Restriction on pipe lengths
• Difficulties as the service is on site; especially the troublesome service of the units inside the suspended ceiling
• If there is an indoor unit in a suspended ceiling, the need for fire detection-extinguishing
• The limited slope of the drainage pipes in the suspended ceiling, drainage difficulties
• Obligation to draw drainage pipes and electrical connections to each indoor unit in the subordinate volumes
• In some projects, the difficulty of acceptance due to the limitations of production countries and