VRF and VRV systems
Variable refrigerant flow systems, sold by Daikin under the VRV name, use one outdoor unit to serve many indoor units and vary refrigerant flow to each. They are common in commercial buildings and report faults with both a code and the address of the unit that raised it.
Also called VRF, VRV, variable refrigerant flow
What is a VRF system?
VRF, or variable refrigerant flow, is a commercial system where one outdoor unit serves many indoor units and modulates the refrigerant sent to each one according to its individual demand.
VRF and VRV systems: how it works
An inverter compressor and electronic expansion valves at each indoor unit let the system deliver a different amount of refrigerant to each space at the same time. A heat recovery arrangement adds branch controllers that let one zone reject heat while another absorbs it, moving heat around the building instead of dumping it outside.
Where you meet the term
- On a commercial fault log, where the code and the unit address together identify what needs attention.
- In a building handover pack, where the addressing scheme maps unit numbers to rooms.
- In refrigerant records, where a large charge and long pipe runs bring leak detection and reporting duties.
How to check it
- Record the code with its address. A VRF code without the unit address is not actionable. Both are shown on the central controller or the outdoor unit display. Technician
- Check whether other units on the same branch are affected. Branch controllers and shared pipework mean a group of units failing together points somewhere different from a single unit failing alone. Technician
VRF and VRV systems: what it is not
- VRV is not a different technology from VRF. It is Daikin's trade name, and the two words describe the same approach.
- A large system charge is not only a performance matter. It sets the leak checking frequency and the record keeping the site owes under F-Gas rules.
VRF and VRV systems questions
What is the difference between VRF heat pump and heat recovery?
A heat pump VRF runs the whole system in one mode at a time. A heat recovery VRF adds branch controllers so some zones can cool while others heat, moving rejected heat to where it is wanted.
Why does a VRF code include a number after it?
The number is the address of the indoor unit or branch that raised the fault. Without it, the same code could point at any one of dozens of units on the system.
Is VRF used in homes?
Occasionally in large properties, but it is designed for commercial buildings with many separately controlled spaces. Residential multi-zone mini-splits cover the smaller version of the same idea.
Where this definition comes from
Written from service manual material held in the HVAC Bench evidence record. Where a document limits a definition to certain models, that limit is repeated here rather than generalised across a brand.
- RZR-P and RZQ-P(9) Series Service ManualSkyAir RZR-P and RZQ-P(9) series equipment listed by Daikin.