Feel the Water
HIU compactUFH

4021

HIU compactUFH

HIU compactfloor heating, compact residential unit, hydraulic interface unit for
hot water production by continuous flow principle and transfer of heat to low-
temperature heating. 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
• 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
Fixed value control with setting range 20°C – 50°C consisting of zone valve,
thermostat with contact sensor, safety thermostat and circulating pump
• 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 module: 15 kg
• Connection: Male thread 3/4“ flat sealing
• Nominal pressure: 10 bar
• Max. supply temp. HIU compactUFH: 70 °C
• Max. supply temperature HIU compactUFH with TSR*: 85 °C
• Min. flow pressure mains cold water: 2,8 bar
• Circulation pump space heating: Wilo Para RS 15/6 (SCU) or similar
• Circulation pump domestic hot water circulation: Wilo Star-Z NOVA or similar


11 l/min


• HIU compactUFH without TSR*: 1 4021 29
• HIU compactUFH with TSR*: 1 4021 26
• HIU compactUFH with TSR*, pipes insulated: 1 4021 32

• HIU compactRAD 55 WW TSR: 1 4025 75
• HIU compactRAD 55 WW TSR, insulated: 1 4025 78
• Domestic hot water circulation 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 compactUFH: 1 4024 09
• Pre-assembly strip HIU compactUFH: 1 4024 49
• Adapter piece for heat meter sensor M 10 x 1 mm: 1 4022 46

 

15 l/min

•HIU compactUFH without TSR*: 1 4021 30
• HIU compactUFH with TSR*: 1 4021 27
• HIU compactUFH with TSR*, pipes insulated: 1 4021 33

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

 

18 l/min
• HIU compactUFH without TSR*: 1 4024 42
• HIU compactUFH with TSR*: 1 4024 87
• HIU compactUFH with TSR*, pipes insulated: 1 4024 92

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

 

22 l/min
• HIU compactUFH without TSR*: 1 4021 31
• HIU compactUFH with TSR*: 1 4021 28
• HIU compactUFH with TSR*, pipes insulated: 1 4021 34

 

Product List

Code Description
  • Sales Unit
1 4021 29 HIU compactUFH without TSR, 11 l/min
  • 1
1 4021 26 HIU compactUFH with TSR, 11 l/min
  • 1
1 4021 32 HIU compactUFH with TSR*, pipes insulated, 11 l/min
  • 1
1 4021 30 HIU compactUFH without TSR, 15 l/min
  • 1
1 4021 27 HIU compactUFH with TSR, 15 l/min
  • 1
1 4021 33 HIU compactUFH with TSR*, pipes insulated, 15 l/min
  • 1
1 4024 42 HIU compactUFH without TSR, 18 l/min
  • 1
1 4024 87 HIU compactUFH with TSR, 18 l/min
  • 1
1 4024 92 HIU compactUFH with TSR*, pipes insulated, 18 l/min
  • 1
1 4021 31 HIU compactUFH without TSR, 22 l/min
  • 1
1 4021 28 HIU compactUFH with TSR, 22 l/min
  • 1
1 4021 34 HIU compactUFH with TSR*, pipes insulated, 22 l/min
  • 1
More Description

Accessories for HERZ HIU compact and HIU LEN

HERZ Stainless steel manifold for HIUs With flowmeter (3 l/min), DN 25, consisting of return manifold with thermostatic valves (M 28 x 1.5), flow manifold with flowmeter inserts. Manifold connection with internal thread G 1", manifold outlets with G ¾" Euro cone. For use in 1 4061 21 Flush-mounted cabinet long for HIU compact accessories clamp sets (1 6098 xx) are to be to be ordered separately.

Order number Description Dim.  Sale Unit 
 1 4023 93 HERZ Stainless steel manifold for HIUs  3x  1
 1 4023 94 HERZ Stainless steel manifold for HIUs  4x  1
 1 4023 95 HERZ Stainless steel manifold for HIUs  5x  1
 1 4023 96 HERZ Stainless steel manifold for HIUs  6x  1
 1 4023 93 HERZ Stainless steel manifold for HIUs  7x  1
 1 4023 98 HERZ Stainless steel manifold for HIUs  8x  1
 1 4023 99 HERZ Stainless steel manifold for HIUs  9x  1
 1 4023 90 HERZ Stainless steel manifold for HIUs  10x  1
 

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