HIU compactRAD, with hot water priority circuit, compact residential unit,
hydraulic interface unit for hot water production by continuous flow principle and
transfer of heat to radiator heaters. Installation as flush mounted version with
flush box or as surface-mounted version with cover. The pipe connection to the
residential unit hydraulic interface unit is created using a patented installation system with pre-installation bracket. Option to connect the pre-installation bracket from the floor.
Consisting of:
•Copper-soldered asymmetrical stainless steel plate heat exchanger
•HERZ pressure and temperature controller for central regulation of the hot water
temperature with hot water priority circuit
•Control valve with return temperature limiter for low heating return temperature
•Constant readiness for hot water production even in summer, operating mode
due to temperature-regulated bypass switching, permanently set to 45°C
•Cold water meter adapter 80 mm – G 3/4" made of dezincification-resistant brass,
also suitable for continuous operation
•Heat meter adapter 110 mm – G 3/4" made of dezincification-resistant brass, also
suitable for continuous operation
•Strainer with fine mesh in primary supply line
•Differential pressure controller with integrated control valve, shut off
valve and zone valve in the secondary circuit
•Differential pressure controller (25 - 60 kPa) in the primary circuit
• Empty weight model: 15 kg
• Connection: Male thread 3/4" flat sealing
• Nominal pressure: 16 bar
• Max. supply temp. HIU compactRAD: 70 °C
• Max. supply temp. HIU compactRAD with TSR: 85 °C
• Min. flow pressure mains cold water: 2,8 bar
• Circulation pump space heating: -
• Circulation pump domestic hot water: Wilo Star-Z NOVA or similar

11 l/min
• HIU compactRAD without TSR*: 1 4021 47
• HIU compactRAD with TSR*: 1 4021 44
• HIU compactRAD with TSR*, pipes insulated: 1 4021 50

• HIU compactRAD 55 WW TSR: 1 4025 75
• HIU compactRAD 55 WW TSR, insulated: 1 4025 78
• Domestic hot water circulatiuon set: 1 4024 73
• Flush cabinet short, 90 mm deep: 1 4024 47
• Flush cabinet short, 150 mm deep
(in combination with circulation set): 1 4021 63
• Front frame with door short: 1 4024 48
• Flush cabinet long, stainless steel distributor connection,
150 mm deep: 1 4021 61
• Front frame with door long: 1 4021 62
• Cover HIU compactRAD: 1 4024 09
• Pre-assembly strip HIU compactRAD: 1 4024 49
• Adapter piece for heat meter sensor M 10 x 1 mm: 1 4022 46

15 l/min
• HIU compactRAD without TSR*: 1 4021 48
• HIU compactRAD with TSR*: 1 4021 45
• HIU compactRAD with TSR*, pipes insulated: 1 4021 51

• HIU compactRAD 55 WW TSR: 1 4025 76
• HIU compactRAD 55 WW TSR, insulated: 1 4025 79

18 l/min
• HIU compactRAD ohne TSR*: 1 4024 41
• HIU compactRAD mit TSR*: 1 4024 46
• HIU compactRAD mit TSR*, pipes insulated: 1 4024 91

• HIU compactRAD 55 WW TSR: 1 4025 77
• HIU compactRAD 55 WW TSR, insulated: 1 4025 80

22 l/min
• HIU compactRAD without TSR*: 1 4021 49
• HIU compactRAD with TSR*: 1 4021 46
• HIU compactRAD with TSR*, pipes insulated: 1 4021 52