目次
- Variable Refrigerant Flow (VRF) heat recovery systems use a single refrigerant loop with branch selector boxes to deliver simultaneous heating and cooling to different zones. Recovered heat from cooling zones is redirected to zones calling for heat, reducing the building net energy use.
- Two-pipe heat-pump VRF can only heat or cool at one time; three-pipe heat-recovery VRF does both simultaneously. The latter is ideal for mixed-use buildings such as offices, hotels and clinics, where perimeter zones need heat while interior cores need cooling.
- VRF recovers thermal energy between zones, but it does not bring in fresh outdoor air. Pairing VRF with a dedicated outdoor-air unit fitted with a 26YC air-to-air plate exchanger delivers code-compliant ventilation without reheating the entire supply stream.
- Size branch circuitry for worst-case simultaneous load, verify refrigerant line lengths against manufacturer limits, and plan for heat-recovery-mode defrost cycles in cold climates.
Variable Refrigerant Flow (VRF) heat recovery systems use a single refrigerant loop with branch selector boxes to deliver simultaneous heating and cooling to different zones. Recovered heat from cooling zones is redirected to zones calling for heat, reducing the building net energy use.
Two-pipe heat-pump VRF can only heat or cool at one time; three-pipe heat-recovery VRF does both simultaneously. The latter is ideal for mixed-use buildings such as offices, hotels and clinics, where perimeter zones need heat while interior cores need cooling.
VRF recovers thermal energy between zones, but it does not bring in fresh outdoor air. Pairing VRF with a dedicated outdoor-air unit fitted with a 26YC air-to-air plate exchanger delivers code-compliant ventilation without reheating the entire supply stream.
Size branch circuitry for worst-case simultaneous load, verify refrigerant line lengths against manufacturer limits, and plan for heat-recovery-mode defrost cycles in cold climates.