Last month, we discussed the role of buffer tanks in combination with air-to-water and water-to-water heat pumps that operate as “on/off” devices. The buffer tank allows the heat pump to operate with reasonably long cycles (e.g., it prevents short cycling) when the hydronic distribution system is heavily zoned, and thus subject to “micro-loading” at times. We also discussed how some buffer tanks can do double duty as both buffers for space heating loads and domestic water heaters. The key concept was to turn the heat pump on and off based on changes in the buffer tank temperatures and not based on thermostats calling for heat.

The new Midea EVOX central inverter heat pump system is one of the most compatible inverter products available and is competitively priced despite some of the highest energy ratings, the company states.