Firstly, we need to know what is a VRV system or VRF system?
A VRV or VRF system is an air conditioning system, it consists of two types of units, the first type is the outdoor unit, and the other type is the indoor unit.
Now, let us talk about the two types of units.
The outdoor unit includes a compressor that controls the flow rate and the volume of the refrigerant.
This control depends on the number of indoor units, and this system is recommended to be used in green buildings.
Also, in the area where the water source for the chilled water system is not easy to be provided like desert places.
As identified in its name, this system is a variable system, which means this system its load is variable not fixed like the direct expansion unit (as split AC unit & Window AC unit).
This system has the ability to allow the thermostat which is installed in each separate space to control the temperature inside this space separately from the other spaces.
This is because each space has its own internal unit.
Note: VRF was invented by a Japanese company called “Daikin”.
There are Two types of VRF systems:
- Air-cooled VRF system.
- Water-cooled VRF system.
Pros or Benefits of VRF or VRV system:
- High efficiency.
- Less power consumption because some of the internal units are switched off, so the load, in this case, will be part load, which will lead to a decrease in the total power consumed.
Cons or disadvantages of VRF system:
- It’s a complicated system compared to the direct expansion system.
- It needs a very well trained people to execute the work because the network of the internal units depends on copper pipes which need welding during the installation.
Important notes on these systems:
- The more distance between the internal & external units, the more cost for installation and operation of the system.
- The outdoor unit of the same system can be connected to different indoor unit types like Cassette, ceiling-mounted unit, wall-mounted unit, Split AC, and so on.
- VRF or VRV system can be a combined system to give cooling and heating at the same time.
- VRF usually used with applications with higher load capacity than 6tons. But in this case, the cost of the Heating/cooling VRF system is more expensive than VRF cooling only or heating only.
Types of pipe routings:
Two pipe system: this system is used when all the indoor units work cooling units only or heating units (not mixed).
Three pipe system: this system is used when some of the indoor units work for cooling, while other indoor units work for heating.
During designing the VRF system, it shall be designed considering all internal units work at the same time (the worst case).
Here, some photos of the practical installations of the VRV system on site
In the above photo, you can see the supports of the copper pipes for the indoor units which will be installed above the false ceiling level.
While this photo is for the outdoor VRV unit on the roof.
I hope that you got a good brief about this system. So, if you like it, please share it with your friends.
If you would like to get a digital copy of the VRF system and its components, please register your email in the following to get it for free. http://engalaxy.com/services/
Also, I recommend you to have a look at my practical online courses in the different electromechanical systems, in these courses you will watch many practical installations videos & photos which are being updated regularly, all these courses can be found on the following link: