
Integrating VRF systems can be quite challenging, even for professionals. Learning how VRF works and asking the “right” questions can present a lot of hassle during integration.
Below are some tips to help you easily integrate VRF systems into home and building automation:
TIP #1 – UNDERSTAND HVAC SYSTEM COMPONENTS
VRF systems consist of two different but equally important system components: indoor units and one or more outdoor units.
The outdoor unit determines the operating states and modes of the VRF systems.
Indoor units operate to achieve individual temperature setpoints for each room and manage desired fan speeds.
TIP #2 – CHECK FUNCTIONS
Home and Building Automation systems have a set of functions to control for each indoor unit. Many integrators may find these terms confusing.
Below you can find the list of functions of your Air Conditioning system:
Operational Status – Is the unit status on / off
Operation Mode – Unit mode Cooling / Heating / Fan / Dry / Auto mode
Temperature Setpoint – The temperature the unit will attempt to reach
Fan Speed – How fast the fan spins High / Medium / Low / Auto
TIP #3 – DO NOT CONTROL THE UNCONTROLLED
Don’t waste time trying to create controls for the outdoor units, focus on the indoor units as these are the only units you need to integrate into your system.

TIP #4 – CHECK EVERY INDOOR UNIT WITH A UNIQUE ADDRESS
When a VRF system is installed, the outdoor unit will automatically assign a unique system address for each indoor unit.
Before starting your integration process, it is important that you first write down a list of all indoor unit addresses along with its location. Doing this before starting the integration will make the process much faster and easier for you!
TIP 5# – SET EACH INDOOR FUNCTION INDEPENDENTLY
Unlike traditional HVAC systems, all VRF indoor unit functions are managed independently. Most VRF indoor units are not affected by the status of any other unit in the system.
For example, the operating state of the living room air conditioner (on / off), the temperature set point, and sometimes even its operating modes (heating / cooling) will be managed independently of the kitchen and bedrooms.
Therefore, although you are used to integrating functions system-wide, you should make sure to integrate functions for each unit separately.
TIP 6# – GROUP UNITS THAT SIMPLIFY CONTROL
When two or more indoor VRF units are connected to operate as a group, only the master unit can be controlled. You should not add any slaves to the automation system, as all slaves will ignore received commands.
TIP 7# – LOOK AT UNIVERSAL SOLUTIONS
While HVAC systems last for 10 to 15 years on average, Home and Building Automation systems can theoretically last forever because their value is found in the underlying automation software, not the hardware interface device.
Since HVAC systems will often be replaced sooner than Home and Building Automation systems, you should encourage your customers and/or HVAC installers to use universal HVAC Automation systems.
Universal solutions will ensure that when the HVAC needs to be replaced, the new system can be easily reintegrated into your Home and Building Automation system.

TIP 8# – FAULT NOTIFICATIONS
Sometimes, after successfully completing an HVAC integration, the HVAC system does not respond to commands. Before restarting the entire integration process, check the HVAC itself for an error notification.
When an error occurs, the error code notification should appear on the HVAC’s wired remote control. However, many Home and Building Automation systems also display the error code on the main controller.
If your Home and Building Automation system does not allow for errors to be forwarded, it would be a good idea to add this functionality as this information can be used by HVAC installers and customers to quickly resolve any HVAC failure.
TIP 9# – DO NOT USE DIFFERENT SETPOINTS FOR VRF SYSTEMS
Traditional HVAC systems (or more specifically, the Thermostats that control them) often use different setpoints for cooling and heating. Most VRF systems operate slightly differently, where usually a single setpoint is used regardless of operational mode.
Since all you need is one, it’s important to remember this so you don’t waste time trying to set up multiple setpoints.
TIP 10# – DO NOT MAKE HARDER HVAC INTEGRATIONS
Many Home and Building Automation integrators have had a bad experience trying to integrate a VRF HVAC system into their Home or Building Automation system. As a result, they find the VRF integration process to be complex and burdensome.
The truth is, these integrations should be incredibly simple (usually just 2 wire connections). Previous bad experiences are probably a result of trying to integrate with the wrong tools! But by using these tips and tricks, Heating and Air Conditioning integrations will become child’s play regardless of system type (VRF, Mini / Multi Split etc.).
BONUS TIP – DON’T BE AFRAID TO ASK FOR HELP!
If you have any questions about HVAC integration, automation or configuration, Coolautomation products will help you.