The Midea 7kW is the smallest unit in the ESG-Inv M Series and the right starting point for a standard 6 x 3 metre pool or a large spa. It carries a rated heating output of 7.16kW under summer conditions and lifts to 10.3kW when boost mode is called, which is what gets a cold pool up to swimming temperature at the start of the season rather than just holding it there.
At 10.5A maximum current it runs off a standard single phase supply without any board upgrade, and at 41dB(A) it is quiet enough to sit near a patio. Silent mode drops that to 39dB(A) at 60 percent capacity, which is the setting most owners leave it on overnight.
Being a full inverter, the unit ramps its output to match what the pool actually needs instead of switching hard on and off. That is where the running cost saving comes from – the compressor spends most of its life at part load, where the coefficient of performance is highest. At low demand this unit reaches a COP of 12.1, meaning roughly twelve units of heat into the water for every one unit of electricity drawn.
Boost mode is worth understanding properly. Ordinary pool heat pumps lose output as the air gets colder, so the unit that heated your pool in December struggles in April. Boost mode on this series holds the same capacity at 15°C ambient that a normal-mode unit only manages at 27°C. In practical terms it extends your usable swimming season on both ends.
Control is through the WiFi app or the 86T wired controller. You get scheduling, a progress bar showing how far the water is from your target temperature, and an energy consumption readout by day, month or year. The controller also stores a service contact number and generates a scannable error code if the unit ever faults, which makes a callout faster and cheaper.
Installation: the heat pump is plumbed inline on the return leg from your existing pool pump – it does not replace your circulation pump and does not need its own. Water connections are 50mm. Electrical connection to the isolator must be done by your own registered electrician.
