Inverter Geothermal Water Source Heat Pump COP 5.6~9.5 Modbus protocol is built inside to be controlled by any other external modbus controller. Support central control. Underground water, lake water even sea water heat source. Work well even minus -45°C air temp. Enery Class A+++ with R32 and R290 refrigerant European standard inverter heat pump With Wifi control function [...]