BS EN 1717:2000 standard applies to water installations and connected appliances inside private and commercial premises.
The EN1717 standard details the type of protection device (if any), required to be used to prevent contamination of potable water in accordance with the potential hazard to human health.
Heat exchangers utilising refrigeration waste heat energy will contain both refrigerant gasses and mineral oil lubricants and so a high level of protecting is required to guarantee food safety.
All types of heat exchangers in direct contact with potable water for drinking and food processing must be manufactured having a twin wall construction with an additional facility to detect possible malfunctions of the heat exchanger such as a crack in the refrigerant pipe.
The DK heat recovery system offers the highest level of protection being twin walled manufacture and with a device that will allow detection of a leak.
It is worth noting that plate heat exchangers do not comply with EN1717 due their inherent design with plates bolted together which can allow water contamination when they fail.
