VRF vs Split System Which is Best for You

VRF or Variable Refrigerant Flow is one of the most common types of commercial air conditioner in the United States but has a lot to offer to the residential air conditioning market in Australia. VRF or VRV (VRV is a trademark of Daikin the original creators of the technology) systems are the newer more advanced form of split or multi-split air conditioning perfect for homes that can't fit ducts for a ducted system but still want efficient whole-home climate control. But what is a VRF system and how does it work?

How a VRF Air Conditioner Works

Air conditioner systems require the refrigerant to be at certain pressures at different stages of the system to ensure the maximum efficiency and longevity of the system. Over the years they have been manufactured in a way that when under load the system works exactly as it should be however problems start arising when the load reduces on the system. As the load reduces the pressures in the system begin to shift which can lead to catastrophic failure of the condenser. The condenser is the heart of the unit it sits in the outside unit and compresses and pumps the refrigerant around the system. The compressor intakes low-pressure cool refrigerant vapour and compresses it to make a high-pressure hot vapour that is sent to the condenser. The condenser requires the intake to be 100% vapour with no liquid in it, as the liquid refrigerant cannot be compressed and can cause serious damage if it were to make its way into the compressor. As the system load decreases the pressures in the system change leading to the inflowing refrigerant gas condensing into a liquid as it enters the condenser. To combat this problem HVAC designers have utilised two main systems to prevent this from happening.

1. Circulation: As the pressure and temperature change in the inflow the system will open a solenoid valve that will then circulate the inflowing refrigerant through a looping pipe until it is at the correct pressure and temperature at which stage it will flow into the condenser. A downside of this system is that the condenser is required to continually run while the refrigerant loops, this wastes energy and puts more wear and tear on the condenser.
2. Cut-Out: When the load decreases on the air conditioner say your home has gotten to the desired temperature the compressor will cut out or shut off then as the load increases it will turn on. This ensures that it’s only running when it is at the optimal load for the system to work as it should. A major downside of this is that switching itself off and on constantly creates extensive wear and tear reducing the longevity of the system. On top of this it is also inefficient and less effective when controlling the temperature of your home as it turns off and on the system will only intermittently cool or heat leading to constant fluctuation in room temperature.

To try and mitigate the downsides of both these control measures HVAC designers from Daikin developed VRF technology. A VRF module on the compressor controls the rate at which the compressor works depending on the load the system is under to ensure the system pressures stay at optimal levels. VRF also opens up a world of opportunities that conventional Circulation and cut-out systems couldn't achieve.

Benefits of VRF

VRF technology allowed HVAC designers to get creative with the possibilities of air conditioning. Probably the biggest benefit of VRF systems is that one outdoor unit can both heat and cool different indoor units simultaneously. This sort of thing was impossible to do with a conventional multi-split aircon they would only allow the system to either all heat or all cool. This made VRF systems highly desirable for hotels and large office buildings as it meant they would only need a handful of outdoor units whereas using a split or multi-split system they would need a different outdoor unit for each room or office. The benefits don't stop there however as this system allows for heat recovery. Heat recovery summed up means if a VRF system fed two rooms and one wanted to be heated but the other cool it could take the heat from the cool room and use it to heat the next room allowing the outdoor condenser to turn off, greatly reducing running costs. This is one of the leading reasons it has become so big in the commercial space but you may be thinking why would this be any good in my residential home? Well let's hypothesise here it's a hot summer day and your home faces north with the sun bearing down on the eastern side of your home heating up those rooms while the rooms at the back of the house are cool from the night before. A heat recovery system will take the heat from the front of the house and distribute it to the back to help offset the outdoor condenser. This will reduce the running costs of your air conditioning system. Vrf systems also put far less wear and tear on the system than a cut-out or a circulation system. VRF systems work other than these technological improvements VRF systems operate as conventional multi-split systems they can be centrally controlled or controlled at each indoor unit. The indoor units can be anything from a wall-mounted split system head, cassettes, and ducted systems to fit your needs and requirements of your home. This gives them far greater flexibility than a split or multi-split system as they allow greater individual temperature control and efficiency.

VRF or Split System

VRF heat recovery systems are some of the most efficient air conditioning systems on the market however they are also some of the most expensive air conditioners on the market. So how do you decide on which is best for your home? Here are some scenarios we find suit each aircon best:

1. If the following sounds like you then a split or multi-split system might be for you:
   • You only want to heat or cool two rooms and they will both either be on heat or cool
   • You are on a tight budget
   • You only have a small home
2. If the next few sound like you then a VRF system might be for you:
   • You have a large multi-room home
   • You require different rooms to be heated or cooled simultaneously
   • You have a bigger budget and are looking for the most efficient system possible
   • You are looking for air conditioning in a large commercial building or office building

If you are still unsure about which system will be right for you don't fret contact our team and we can help point you in the right direction. With extensive residential air conditioning know how our team will be able to work with you to get an air conditioner that will meet your needs and expectations. In conclusion, VRF systems offer superior efficiency, flexibility, and control compared to traditional split systems, making them ideal for large commercial buildings, offices, and large multi-room homes where individual temperature control and energy savings are critical.