Where I live it’s against building code for hot water to be kept below 60C, due to the potential for growth of water-borne pathogens. A hot water tank that allows water to fall to 45C would not be allowed. In practice, the companies who supply water heaters set them much higher than 60C to avoid the risk of water cooling below that temperature during extended power outages.
I don’t know what specific pathogens you are talking about, but the classic risk is Legionella, which gets killed at only 55°C.
The heatpump is aware of this, and has built in additional electric heaters, and combine the electric heaters with the regular heatpump cycle to heat the water up to temperatures beyond 60°C regularly to keep the water pathogen free.
Where I live it’s against building code for hot water to be kept below 60C, due to the potential for growth of water-borne pathogens. A hot water tank that allows water to fall to 45C would not be allowed. In practice, the companies who supply water heaters set them much higher than 60C to avoid the risk of water cooling below that temperature during extended power outages.
I don’t know what specific pathogens you are talking about, but the classic risk is Legionella, which gets killed at only 55°C.
The heatpump is aware of this, and has built in additional electric heaters, and combine the electric heaters with the regular heatpump cycle to heat the water up to temperatures beyond 60°C regularly to keep the water pathogen free.