The Midea 9kW sits between the entry unit and the 12kW, and it is the size most 8 x 4 metre pools land on. Rated output is 9.15kW in summer conditions, rising to 12.8kW with boost engaged. If your pool is uncovered, treat this as the unit for a 25,000 litre pool rather than a 32,000 litre one – evaporation off an open surface is the single biggest heat loss you are fighting.
Maximum current draw is 11A, so like the 7kW it runs on a standard single phase supply. Running noise is 43dB(A), dropping to 39dB(A) in silent mode at 60 percent capacity.
The inverter compressor varies its speed against demand rather than cycling on and off at full output. Most of the time the unit is holding temperature rather than climbing to it, and that is where an inverter earns its price difference over a fixed-speed pump – part load is where the coefficient of performance peaks, at 12.1 on this model.
Boost mode addresses the problem every pool owner notices in April. Heat pump output falls as ambient air temperature drops, so the unit that coped in midsummer no longer keeps up. Boost mode on the ESG-Inv M Series maintains full capacity down to 15°C ambient – the same output a normal-mode heat pump would only give you at 27°C.
The unit is controlled from the WiFi app or the 86T wired controller. Both give you scheduling, a percentage progress readout toward your set temperature, and energy consumption logged by day, month and year so you can see exactly what the pool is costing to heat.
Installation: plumbed inline on the return from your existing pool circulation pump, with 50mm water connections. The heat pump does not replace your pool pump. Electrical connection at the isolator is done by your own registered electrician.
