Hamworthy Heating

Varmax mk2 floor standing boiler

  • Floor standing, high output condensing boiler with a stainless steel heat exchanger.
  • 6 models in the range with outputs of 180 - 450kW
  • Hamworthy Web Icons JBs base set BLUE Product-icon-efficiency-96
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Basic Varmax images-Layout 1-wider-2
Basic Varmax images-Layout 1 2-wider-2

Product information

  • Improved efficiency on split temperature systems due to high and low temperature return connections.

  • Non-dependent on system flow allowing wide differential temperatures.

  • Easier installation with no requirement for dedicated primary circuit and no minimum flow rates.

  • Touch screen controls for simple, intuitive set up.

  • Quick and easy to disassemble with updated casing access, also meaning easier access for maintenance or service.

  • Tolerant to a wide range of system water conditions with a corrosion resistant stainless steel heat exchanger.

  • Long life backed up by a 5-year heat exchanger warranty.

  • Well insulated for low standby losses.

  • NOx emissions comply with ErP legislation lower than 56mg/kWh.

  • Match heating system loads accurately with outputs up to 450kW from a single boiler and ability to cascade multiple boilers.

  • Simplified flue system design as the flue gas non-return valve is built in to provide effective protection from re-circulation of flue gases through non-firing boilers.

  • Built in boiler sequence controls capable of controlling up to 16 boiler modules, multiple heating circuits and a hot water circuit using the master/slave principle.

  • Quick release access panels for ease of service and maintenance.

  • BIM objects available to assist in design and management.

Ideal uses/applications

Optional extras

  • A large range of off the shelf flue options available

  • Room sealed and open flue solutions

  • Flue header kits

Single Boiler Controls

  • Outside air temperature sensor QAC34 (Part no. 533901457)

  • Domestic Hot Water sensor kit (sensor and pocket) QAZ36 (Part no. 563605674)

  • Mixing valve heating circuit control kit (AVS 75 control module, temperature sensor and pocket) for 1 zone (Part no. 059751)

  • Programmable room sensor QAA75 (Part no. 533901587)

  • Offset adjustable room sensor QAA55 (Part no. 533901589)

Multiple Boiler Controls

  • Outside air temperature sensor QAC34 (Part no. 533901457)

  • Heating circuit sensor kit (sensor and pocket) QAZ36 (Part no. 563605673)

  • Merley boiler sequence controller, wall mounted (Part no. 563605672)

  • LPB Bus communication module OCI345, one required per boiler module (Part no. 563605667)

  • Programmable room sensor QAA75 (Part no. 533901587)

  • Offset adjustable room sensor QAA55 (Part no. 533901589)

  • Choose from a wide range of service contracts to help maintain optimum performance.

  • Book commissioning at the same time as placing your order for improved warranty terms.

  • Energy

    Units

    180

    225

    275

    320

    390

    450

    Building regulations Part L seasonal efficiency

    % gross

    96.3

    96.3

    96.2

    96.2

    96.2

    96.2

    Boiler output - maximum 80/60°C, NG & LPG*

    kW

    175.9

    219.8

    269.5

    313.6

    382.3

    441.9

    Boiler output - maximum 50/30°C, NG & LPG*

    kW

    191

    238

    290

    338

    415

    478

    Boiler output - minimum 80/60°C, Nat Gas.

    kW

    43

    43

    66

    66

    87

    87

    Boiler input (gross) - maximum, NG & LPG*

    kW

    180

    225

    275

    320

    390

    450

    Boiler input (net) - maximum, NG & LPG*

    kW

    162

    203

    248

    288

    351

    405

  • Water

    Units

    180

    225

    275

    320

    390

    450

    Water content

    litres

    151

    151

    239

    239

    287

    287

    System design flow rate @ 30°C ΔT rise

    l/s

    1.4

    1.7

    2.1

    2.5

    3

    3.5

    Water side pressure loss @ 30°C ΔT rise

    mbar

    25

    36

    36

    53

    34

    43

    System design flow rate @ 20°C ΔT rise

    l/s

    2.1

    2.6

    3.2

    3.7

    4.6

    5.3

    Water side pressure loss @ 20°C ΔT rise

    mbar

    49.5

    73.5

    110.6

    127.3

    85

    107

    System design flow rate @ 11°C ΔT rise

    l/s

    3.8

    4.7

    5.8

    6.8

    8.3

    9.5

    Water side pressure loss @ 11°C ΔT rise

    mbar

    188

    268

    271

    393

    255

    321

    Maximum water pressure

    barg

    6

    6

    6

    6

    6

    6

    Maximum flow temperature setting

    °C

    85

    85

    85

    85

    85

    85

  • Gas

    Units

    180

    225

    275

    320

    390

    450

    Gas flow rate, NG (G20) - maximum

    m³/hr

    19.1

    23.8

    29.1

    33.9

    41.3

    47.6

    Maximum gas inlet pressure, Nat Gas

    mbar

    25

    25

    25

    25

    25

    25

    Nominal inlet pressure, Nat Gas

    mbar

    20

    20

    20

    20

    20

    20

  • Flue

    Units

    180

    225

    275

    320

    390

    450

    Maximum flue gas temperature @ 80/60°C Nat Gas

    °C

    61

    62.3

    61.7

    63.4

    62.5

    64.8

    Pressure at boiler flue spigot @ 80/60°C Nat Gas B23P

    Pa

    115

    165

    122

    176

    180

    193

    Dry NOx emission**

    mg/kWh

    27

    27

    36

    36

    32

    35

    NOx Class

    6

    6

    6

    6

    6

    6

  • Electrical

    Units

    180

    225

    275

    320

    390

    450

    Electrical supply

    230V, 1Ph, 50Hz

    230V, 1Ph, 50Hz

    230V, 1Ph, 50Hz

    230V, 1Ph, 50Hz

    230V, 1Ph, 50Hz

    230V, 1Ph, 50Hz

    Power consumption - maximum boiler modulation

    W

    228

    330

    326

    427

    545

    717

    Approx shipping weight

    kg

    393

    393

    502

    502

    592

    592

    Noise emission @1m: @max. modulation

    dB (A)

    76

    76

    77

    77

    84

    89

Partnerships

CIBSE Patron WhiteSoPHE Logo
BESA logo
ICOM

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