Residential Multi-Function Heat Pump Laboratory Testing

Residential Multi-Function Heat Pumps (MFHP) use one efficient compressor to provide space cooling, space heating, and domestic hot water heating. MFHPs have lower peak power consumption compared to the typical two separate heat pumps, for space conditioning and water heating, and may enable retrofit electrificaiton without electrical service panel upgrades reducing cost and installation time. This project laboratory tested a commercially available single-speed MFHP measuring capacity and energy consumption in all operating modes across a range of outdoor conditions that match California climate zones. The measured results were analyzed to develop performance curves that will be used by future projects to estimate annual energy savings in residential buildings across climate zones. At 95℉ outdoor and 80℉ indoor temperatures, the space cooling capacity was 45.3 kBTUh at a COP of 3.57. Waste heat recovery from space cooling for heating hot water saved an average of 38% of electrical energy compared to separate cycles.