The present certification scheme covers Heat Interface Units, defined as a packaged unit including at least one Domestic Hot Water heat exchanger and control elements.
The HIU may contain:
The HIU covered by the scheme are 3 pipes configurations. HIU with DHW capacity level above 70 kW are not covered by the certification scope. Only units for single family dwellings use are covered.
The covered technologies are:
Symbol |
Signification |
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Pump |
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|
Heat Exchanger |
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Mixing valve |
Heat Interface Unit
Packaged unit including one or more heat exchangers, control elements transferring heat from a primary to a secondary system. The primary system may be a district or communal heating scheme. The secondary system is the space heating or domestic hot water system within the dwelling of other space.
Direct Heating
Primary system and secondary system for space heating are directly connected through the HIU without any heat exchanger. Primary and secondary system are supplied with the same water and pressure. Space heating temperature flow isn’t controlled by mixing loop.
Direct Heating Mixed
Primary system and secondary system for space heating are directly connected through the HIU without any heat exchanger. Primary and secondary system are supplied with the same water and pressure. Space heating temperature flow is controlled by a mixing loop.
Indirect Heating
Primary system and secondary system for space heating are indirectly connected through the HIU with a heat exchanger separating both systems. Primary and secondary system are not supplied with the same water and pressure.
The following performance data declared by the applicant/participant are verified by tests:
Certified Performances |
Unit |
Technology type concerned |
Maximal DHW capacity |
kW |
All 4 technologies |
Return temperature during normal DHW tapping |
°C |
|
Minimal DHW flow rate |
l/min |
|
>DHW reaction time |
>s |
|
DHW Standby heat losses |
kW |
|
Capacity on temperature delta of 20 K |
>kW |
DH |
Capacity on temperature delta of 10 K |
kW |
>DHM |
Difference between primary return temperature and secondary return temperature at 4kW |
°C |
>IH |
Heat losses |
kW |
DH, DHM, IH |