2. Baxi AquaHeat HIUs

Commercial Solutions

Heat Interface Units

For homes fed with heat from a heat network, the Baxi AquaHeat HI/HWI (Heating Indirect/Hot Water Indirect) is the answer to your apartment’s heating and hot water requirements.


The Baxi AquaHeat HD/HWI (Heating Direct/Hot Water Indirect) provides an alternative highly efficient, low cost solution and the Baxi AquaHeat HI (Heating Indirect) is perfectly suited to supply heat to communal and commercial premises in your development.

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    Features and Benefits

    Multiple outputs

    Range of heating outputs from 4kW to 60kW and domestic hot water outputs from 18kW to 57kW.

    Easy installation

    Optional first fix rail with in-built filling loop and stand-off bracket to allow for installation with various primary and tertiary pipework. Pre-wired with heat meter and Mercurius remote monitoring module.

    Highly efficient

    Ultra-fast acting, fully modulating PICV perfectly matches energy supply to instantaneous demand and high performance insulation providing very low heat losses.

    Remote monitoring and control

    Mercurius platform for remote monitoring to reduce site on time and giving visibility of errors to improve first-time fix rates.

    Reliable

    Water Regulation WRAS and Reg4 approved. BESA 2023 V3 compliant in preparation for HNTAS market regulation. Covered with a 5-year parts and labour warranty.*

    BESA 2023 V3 accredited

    High performing Indirect HIU with 8 best practice passes. The first BESA 2023 certified Direct HIU with best practice Heat Loss performance.
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    Product Literature

    Specification Guides

    Specification Guides

    Technical Specifications

    Technical Specifications

    BIM Files

    BIM Files

    Baxi Aquaheat HIU

    Baxi AquaHeat HIU
    BIM file

    Reports

    Reports

    Baxi AquaHeat HIU - Heat Interface Unit Dimensions

    AquaHeat HI

    Dimensions

    A: HIU width = 540mm 

    B: HIU height = 857mm

    C: HIU depth = 260mm

    D: Side Clearance = 30mm

    E: Upper Clearance =100mm

    F: Lower Clearance = 30mm

    G: Front Clearance (in operation) = 200mm 

     

    Service clearances shown here are the minimum

    recommended dimensions. Greater clearance will 

    aid installation and maintenance.      

    Baxi AquaHeat HI/HWI Heat Interface Unit Dimensions

    AquaHeat HI/HWI

    Dimensions

    A: HIU width = 540mm

    B: HIU height = 750mm

    C: HIU depth = 260mm

    D: Side Clearance = 30mm

    E: Upper Clearance = 100mm

    F: Lower Clearance = 30mm

    G: Front Clearance (in operation) = 200mm 

     

    Service clearances shown here are the minimum

    recommended dimensions. Greater clearance will 

    aid installation and maintenance.      

    aquaheat-hdhwi-dimensions.png

    AquaHeat HD/HWI

    Dimensions

    A: HIU width = 300mm

    B: HIU height = 544mm

    C: HIU depth = 250mm

    D: Side Clearance = 30mm

    E: Upper Clearance = 30mm

    F: Lower Clearance = 100mm

    G: Front Clearance (in operation) = 200mm

     

    Service clearances shown here are the minimum 
    recommended dimensions. Greater clearance will 
    aid installation and maintenance.

    Technical Specification 

    Product ModelAquaHeat HI/HWI - 4/50AquaHeat HI/HWI - 4/50AquaHeat HI/HWI - 14/50AquaHeat HI/HWI - 14/50AquaHeat HI - 50AquaHeat HI - 50AquaHeat HD/HWI - 12/50AquaHeat HD/HWI - 12/50
    with Heat Meter & Mercuriuswith Heat Meter & Mercuriuswith Heat Meter & Mercuriuswith Heat Meter & Mercurius
    Product Code78674707867472786747678674777867474786747578922847892283
    Net Weight (Dry) (kg)2726.52726.7303010.510.5
    Net Weight (Wet) (kg)27.52727.527.231.531.51111
    Gross Weight (packaged) (kg)2726.52726.7303010.510.5
    Height (packaged) (mm)750750750750857857544544
    Width (packaged) (mm)540540540540540540300300
    Depth (packaged) (mm)260260260260260260250250
    Heat Loss in keep warm mode high temp (DH 70°C) (kWh / 24h)0.950.950.950.95--0.610.61
    Heat Loss in keep warm mode low temp (DH 55°C) (kWh / 24h)0.910.910.910.910.690.69
    Primary Side
    Max operating pressure (bar)16161616161666
    Max operating temperature (˚C)9090909090909090
    Maximum primary flow rate (DHW mode) (55 primary / 50 dhw (m3/h)0.90.90.90.9--0.90.9
    Maximum primary flow rate (space heating mode) (55 primary / 45/35 CH) (m3/h)0.260.260.60.6330.50.5
    Maximum primary pressure differential (kPa)600600600600600600
    Min primary pressure drop req. at Maximum primary flow rate (DHW Mode) (kPa)16161616--1616
    Space Heating hydraulics
    Max operating pressure (bar)2.52.52.52.53366
    Max operating temperature (˚C)8585858585859090
    Safety relief valve setting (bar)333333N/AN/A
    Heating temperature setpoint (min - max) (˚C)15 - 8515 - 8515 - 8515 - 8515 - 8515 - 8515 - 9015 - 90
    Heating temperature setpoint (default) (˚C)4545454545455555
    Heating nominal pump head (kPa)70707070--N/AN/A
    DHW hydraulics
    Max operating pressure (bar)10101010--1010
    Min cold water supply pressure (bar)1111--11
    Hot water temperature setpoint (min-max) (˚C)40-6540-6540-6540-65--40 - 6540 - 65
    Hot water temperature setting (default) (˚C)50505050--5050
    Electrical
    Power supply (V / Hz)230V ~50 Hz230V ~50 Hz230V ~50 Hz230V ~50 Hz230V ~50 Hz230V ~50 Hz230V ~50 Hz230V ~50 Hz
    Permanent live required (yes/no)yesyesyesyesyesyesyesyes
    Power consumption (max space heating output) (W)6565656565656565
    Power consumption (standby) (W)33333333
    Power consumption (max space heating output, with Mercurius) (W)7575757575757575
    Power consumption (standby, with Mercurius) (W)1313131313131313
    Minimum external fuse rating (A)55555555
    Internal fuse rating (A)55555555
    Connection Types / Sizes
    Primary network flow3/4 ISO G 228 male3/4 ISO G 228 male3/4 ISO G 228 male3/4 ISO G 228 male1 female1 female3/4 ISO G 228 male3/4 ISO G 228 male
    Primary network return3/4 ISO G 228 male3/4 ISO G 228 male3/4 ISO G 228 male3/4 ISO G 228 male1 female1 female3/4 ISO G 228 male3/4 ISO G 228 male
    Space heating flow3/4 ISO G 228 male3/4 ISO G 228 male3/4 ISO G 228 male3/4 ISO G 228 male1 female1 female3/4 ISO G 228 male3/4 ISO G 228 male
    Space heating return3/4 ISO G 228 male3/4 ISO G 228 male3/4 ISO G 228 male3/4 ISO G 228 male1 female1 female3/4 ISO G 228 male3/4 ISO G 228 male
    Cold water feed3/4 ISO G 228 male3/4 ISO G 228 male3/4 ISO G 228 male3/4 ISO G 228 male1 female1 female3/4 ISO G 228 male3/4 ISO G 228 male
    Domestic hot water flow3/4 ISO G 228 male3/4 ISO G 228 male3/4 ISO G 228 male3/4 ISO G 228 male1 female1 female3/4 ISO G 228 male3/4 ISO G 228 male
    Space heating safety valve discharge (mm)151515151212N/AN/A

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