Objective:

  • Block diagram of VRV/VRF system.
  • Refrigeration cycle of VRV/VRF system.

History:

  • 1982 VRV – Daikin developed VRV, the world’s first multi-split type air conditioner for commercial buildings.
  • VRV and VRF are two different terms for the same technology . Because VRV is a trademark of Daikin Industries, Ltd., all other companies that copy this technology refer to it as a VRF system.

Block diagram of VRV/VRF

Type of compressor used in VRV/VRF system

  • Inverter scroll compressor
  • Digital scroll compressor

Refrigerant used in VRF/VRV system

  • R-410A -RF systems use R-410A refrigerant as the heat-transfer fluid and the working fluid, achieving a very high energy efficiency ratio (EER) of 15 to 20 and integrated energy efficiency ratio (IEER) of 17 to 25.
  • R-410 C -One benefit of using R-407C at high-ambient conditions is that it operates at relatively low pressure.

VRV/VRF Refrigeration cycle

Working Of Inverter Compressor

Inverter compressor uses a variable frequency drive – also known as inverter drive– to slow down or speed up the motor that rotates the compressor. This method varies refrigerant flow by actually changing the speed of the compressor. The turndown ratio depends on the system configuration and manufacturer.

Split Air conditioning system

A split air conditioner consists of an outdoor unit and an indoor unit. The outdoor unit is installed on or near the exterior wall of the room that you wish to cool. This unit houses the compressor, condenser coil and the expansion coil or capillary tubing. The sleek-looking indoor unit contains the cooling coil, a long blower and an air filter.

Advantage of VRF/VRV system

  • Consistent comfort.
  • Quiet operation.
  • Energy efficiency.
  • Installation flexibility for small spaces.
  • Heat & cool simultaneously for zoned comfort.
  • State of the art controls & smart technology.
  • Fewer breakdowns and less downtime.

The disadvantages of VRF systems include:

  • The need for a dedicated ventilation system to deliver the outside air to various zones.
  • Long refrigerant lines and a large number of branch connections could result in refrigerant leakage.
  • The need for condensate drain lines for each VRF indoor unit.

Applications for a VRF system include:

  • Large retail spaces
  • Hotels, motels, and  other lodgings
  • Office structures
  • Apartment buildings
  • Assisted living
  • Condominium complexes
  • Universities
  • Dormitories
  • Data centers
  • Hospitals Manufacturing plants
  • Lab facilities
  • Restaurants
  • Anywhere that requires simultaneous heating and cooling over multiple zones

Types of Indoor units connected to VRF system

  • Wall mounted split system
  • In-ceiling cassette System
  • Ceiling mounted cassette round flow
  • Ceiling mounted cassette double flow type
  • 4- way ceiling suspended type
  • Ceiling mounted cassette corner type
  • Ceiling mounted duct type ac