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VRF Diversity Calculator
Calculate the VRF/VRV diversity factor and connection ratio. Check whether your outdoor unit is correctly sized for the total indoor unit capacity.
Understanding VRF Diversity
The connection ratio (indoor/outdoor capacity) indicates how much the outdoor unit is 'overloaded' relative to the indoor units. Most VRF manufacturers allow up to 130% connection ratio.
A higher connection ratio means the outdoor unit is smaller relative to the indoor units, which is acceptable because not all zones peak simultaneously. However, if all zones call for full capacity, the outdoor unit can't keep up.
Frequently Asked Questions
What is a good VRF connection ratio?
80–130% is typical. Most manufacturers allow up to 130%. Going above 130% risks insufficient capacity when all zones peak simultaneously.
What happens if the connection ratio is too high?
If all zones call for full capacity simultaneously, the outdoor unit can't deliver enough refrigerant, and some indoor units will underperform. The BMS or controller prioritises zones.
VRF Diversity Calculator
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