What do we mean by heat recovery & heat pump in VRV residential central air conditioning systems?

October 05, 2020 | 07:15 AM

Two formats dominate VRV residential central air conditioning systems — heat recovery and heat pump.

Heat recovery system VRVs:

• Heat recovery VRVs can be either two pipe or three pipe systems and have the ability to heat certain zones while cooling others
• They use a two-pipe system featuring a branch circuit controller to the individual indoor evaporator zones. The heat extracted from zones needing cooling is then applied to zones needing heating. Other manufacturers use a three-pipe system to accomplish the same function
• Heat recovery VRF systems allow for additional performance efficiency by providing the capability of capturing heat from a zone that requires cooling and reusing it in a zone the requires heating. This allows multiple diverse zones to be connected to a single set of central compressors, possibly resulting in a lower installed overall nominal tonnage when compared to using multiple independent systems
• They allow for extended refrigerant line lengths for increased installation flexibility and inverter duty compressors for improved operational resiliency with the ability to operate the unit at lower outdoor ambient conditions

Heat pump VRV systems:

• Heat pump VRVs typically are two-pipe systems that operate similarly to the heat-recovery system, but lack the flexibility of meeting both cooling and heating needs. All zones must be either cooling or heating
• While this increases overall energy consumption of the facility, the installed cost is lower, and the system and its control valves are less complex, resulting in lower maintenance costs long term

VRV systems are capable enough to reuse heat from various rooms through the refrigerant pipe using heat recovery technology. They can reuse heat from places like the server and offices for providing heat to other areas according to the user’s needs. Moreover, the importance of an HVAC system or a VRF HVAC system in commercial and residential buildings cannot be overemphasized. This technology circulates only the minimum amount of refrigerant needed at any one time and thus enables individual climate control of air conditioning zones.