Wessex ModuMax modular boiler
Wessex ModuMax mk3 modular boiler with pipekits
Wessex ModuMax modular boilers
Wessex ModuMax mk3 modular boiler
Wessex ModuMax mk3 modular boiler installed at St Paul's Cathedral

Stainless steel high efficiency, fully modulating condensing pre-mix floor standing boiler.

Available in 5 modules with outputs (@80/60°C) of 97, 116, 147, 196 and 254kW. Individual boiler modules can be stacked one, two or three high in 15 combinations up to 762kW output.

Efficiency 95 product icon
Fuel NG LPG product icon
Turndown 15 product icon
Warranty 10 heat exchanger product item
ErP Part L Compliant product icon
BIM objects icon

Product information

    • Fully modulating boiler which benefits from lower fuel usage and closer load matching.
    • Space-saving stacked modular boiler delivering 762kW in less than a square metre footprint.
    • Flexibility in system design with differential temperature (delta T) up to 40°C. Suited to district heating schemes, the lower flow rates associated with wider differential temperature allow smaller diameter pipes and smaller pumps that can lower capital cost and also reduce energy consumption.
    • Compensate for distribution losses in large heating systems with max 90°C flow temperature.
    • 10 bar maximum working pressure allows installation in basement for high rise buildings.
    • Stainless steel heat exchanger backed up by with a 10-year warranty, making the Wessex ModuMax mk3 an extremely robust boiler.
    • High relative velocity within the waterways help to reduce the opportunity for sedimentation.
    • Low water content, rapid response, with minimal standing losses.
    • Built in boiler sequence controls capable of controlling up to 16 boiler modules and hot water circuits.
    • Low environmental impact - NOx <40mg/kWh for maximum BREEAM credits.
    • Easy access to plant room as the lightweight and compact Wessex ModuMax mk3 fits through a standard doorway and can split into modules for limited access or rooftop plant rooms, as well as packaged plant rooms.
    • Buy in confidence from a UK manufacturer with decades of commercial heating and hot water expertise.
    • Back up and support from our team of experienced engineers across the UK.
    • Extensive boiler spare parts service available direct from the manufacturer.
    • BIM objects available to assist in design and management.

Technical data

Units 97/97H
No. of modules 1
Energy
Building regulations Part L seasonal efficiency % gross 94.9
BS EN 15502 seasonal efficiency % gross 95.2
Boiler output 80/60°C, NG & LPG kW 95.7
Boiler output 50/30°C, NG & LPG kW 97.2
Boiler input (gross) - maximum, NG kW 109
Boiler input (gross) - maximum, LPG kW 106.7
Boiler input (net) - maximum, NG & LPG kW 98.2
Boiler output - minimum 80/60°C, NG & LPG kW 19.1
Water
Water content litres 16
System design flow rate @ 40°C ∆T rise l/s 0.6
Water side pressure loss @ 40°C ∆T rise mbar 5
System design flow rate @ 30°C ∆T rise l/s 0.8
Water side pressure loss @ 30°C ∆T rise mbar 9
System design flow rate @ 20°C ∆T rise l/s 1.2
Water side pressure loss @ 20°C ∆T rise mbar 20
System design flow rate @ 11°C ∆T rise l/s 2.2
Water side pressure loss @ 11°C ∆T rise mbar 61
Maximum water pressure barg 10
Maximum flow temperature setting °C 90
Gas
Gas flow rate, NG (G20) - maximum m3/hr 10.4
Gas flow rate, LPG (G31) - maximum m3/hr 4
Nominal inlet pressure, NG (LPG) - maximum mbar 20 (37)
Maximum gas inlet pressure NG (LPG) mbar 25 (45)
Flue
Approx. flue gas volume @ 15°C, 8.75-9.25% CO2 m³/hr 143
Maximum flue gas temperature @ 80/60°C °C 83
Pressure at boiler flue connection Pa mbar 150 1.5
NOx emission (0% excess oxygen, dry air free) - NG mg/kWh 39.8
NOx emission (0% excess oxygen, dry air free) - LPG mg/kWh 42
Connection
Water flow/return connections inches G1½" male
Gas inlet connection pipe thread size inches R1" male
Nominal flue diameter (I/D) mm 100
Condensate trap connection(s) (O/D) mm 32
Electrics
Electrical supply 230 V 1 Ph 50 Hz
Power consumption - maximum boiler modulation W 166
Start current (per module) Amp 1.2
Run current (per module) Amp 0.72
Approx shipping weight kg 180
Noise emission @1m @maximum modulation Max dB (A) 60
Noise emission @1m @minimum modulation Min dB (A) 47

Downloads

Wessex ModuMax mk3 boiler brochure

Product brochures 6125 kb

500001305-B QAA73.210 Programmable Room Unit Guide.pdf

Installers guides 1783 kb

AGU 2.550 Kit instructions

Installers guides 445 kb

LPB Expansion Kit Instructions

Installers guides 2358 kb

Navistem B3000 controller instruction manual

Installers guides 2177 kb

QAA55 room unit programming instructions

Installers guides 153 kb

QAA74 - Technical Manual

Installers guides 1640 kb

QAA74 Quick Reference Guide

Installers guides 178 kb

Siemens room operator units QAA55, QAA75, QAA78, AVS13, AVS14, AVS71

Installers guides 6621 kb

Volt Free Contact (VFC) and switch fitting instructions

Installers guides 1349 kb

Wessex ModuMax mk3 Installers Guide

Installers guides 6887 kb

Wessex ModuMax mk3 user instructions

Installers guides 76 kb

Wessex ModuMax mk3 scheme 1 open vented with low loss header

Hydraulic schematics 78 kb

Wessex ModuMax mk3 scheme 2 sealed primary with open vented second and plate heat exchanger

Hydraulic schematics 71 kb

Wessex ModuMax mk3 scheme 3 single pipe, pump per boiler and LLH

Hydraulic schematics 73 kb

Wessex ModuMax mk3 scheme 4, single pipe with independent DHW

Hydraulic schematics 86 kb

Pump Upgrade Kit Installation Guide (sketch)

CAD 11634 kb

Wessex ModuMax mk3 boiler 97-97H CAD

CAD 2040 kb

Wessex ModuMax mk3 boiler 116-232V CAD

DWG 3233 kb

Wessex ModuMax mk3 boiler 116-348V CAD

DWG 4650 kb

Wessex ModuMax mk3 boiler 116-348V with pipekit CAD

DWG 4818 kb

Wessex ModuMax mk3 boiler 147-147H CAD

DWG 2125 kb

Wessex ModuMax mk3 boiler 147-294V CAD

DWG 3155 kb

Wessex ModuMax mk3 boiler 147-294V with pipekit CAD

DWG 3888 kb

Wessex ModuMax mk3 boiler 147-441V CAD

DWG 4533 kb

Wessex ModuMax mk3 boiler 147-441V with pipekit CAD

DWG 5381 kb

Wessex ModuMax mk3 boiler 196-196H CAD

DWG 2125 kb

Wessex ModuMax mk3 boiler 196-392V CAD

DWG 3155 kb

Wessex ModuMax mk3 boiler 196-392V with pipekit CAD

DWG 3888 kb

Wessex ModuMax mk3 boiler 196-588V CAD

DWG 4533 kb

Wessex ModuMax mk3 boiler 196-588V with pipekit CAD

DWG 5381 kb

Wessex ModuMax mk3 boiler 254-254H CAD

DWG 2125 kb

Wessex ModuMax mk3 boiler 254-508V CAD

DWG 3155 kb

Wessex ModuMax mk3 boiler 254-508V with pipekit CAD

DWG 3888 kb

Wessex ModuMax mk3 boiler 97-194V with pipekit CAD

DWG 3458 kb

Wessex ModuMax mk3 boiler 97-291V CAD

DWG 4650 kb

Wessex ModuMax mk3 boiler 97-291V with pipekit CAD

DWG 4818 kb

Wessex ModuMax mk3 boiler 116-232V with pipekit CAD

CAD,DWG 3458 kb

Wessex ModuMax mk3 boiler 254-762V CAD

CAD,DWG 4533 kb

Wessex ModuMax mk3 boiler 254-762V with pipekit CAD

CAD,DWG 5381 kb

Wessex Pump Kit

5095 kb

Testimonials

Space was tight in the plant room but Wessex ModuMax boilers can cope with the base load for the school with ease: The choice was easy. They also deliver great efficiency.

Philip Johnson, Pick Everard

The Wessex modular boilers were the best product to fit in the available space. I have used them in many previous installations so I know how reliable they are.

Danny Bulch, Cedar Green Projects ltd

We like using the Wessex ModuMax modular boilers as they are a reliable range and simple to service.

Jason Collyer, JCS

We chose the Wessex because it delivers a high output from a small footprint and it’s a tried and tested product with stainless steel heat exchanger. Thanks to its compact size, the Wessex fitted onto the footprint of only one of the old boilers, so we’ve effectively halved the space needed for the heating equipment.

Danny Bulch, Cedar Green Projects ltd

We chose the Wessex ModuMax mk3 boilers due to their slim profile and the 10 bar working pressure. It’s also efficient, streamline, compact, and easy to use. I chose the pipe header because they’re a simple piece of kit with a plug and play installation.

SPIE senior project manaager

I have a really good working relationship with Hamworthy, and chose the Wessex ModuMax product for this installation as I knew it was a product I could rely on. The compact, vertically-stacking, design also means it can easily fit in the available space.

Adrian Lusty, MIH Ltd

We have been really pleased with the outcome of the project. Since having the new boilers and BMS installed we have to date seen a saving of around 22% in our gas bill across the whole site.

Tim Partridge, Regional Buildings & Maintenance Co-Ordinator, Cheltenham Racecourse

The modular boilers solution enables close load matching and using multiple boilers increases system security – a crucial factor for a hotel that can’t be without heating or hot water. With access difficult and space in the plant room tight, the vertically stacking design meant the Wessex ModuMax boilers were best suited.

Steve Collins, Director, Kontrax Management Ltd

The developer wanted to maximise the space available for flats and grounds which meant we had to design the plant rooms to be as compact as possible. Wessex ModuMax boilers were specified as they can be stacked vertically and fit on a very small footprint taking up minimal space in the plant rooms.

Nigel Hawkes, Technical Associate, Mott MacDonald

Ideal uses/applications

  • Energy centres within district heating schemes and larger premises.
  • Housing developments and flats using district heating networks.
  • Hybrid systems alongside combined heat and power (CHP) and/or other renewable technologies such as biomass boilers.
  • Easy fit replacement for refurbishment projects.
  • Roof top and basement plantrooms.
  • Packaged plantrooms.
  • New build projects.
  • Large commercial and public buildings including schools, hospitals and hotels.
  • Medium sized commercial and public buildings including schools, hospitals, offices and hotels.
  • Small industrial and manufacturing premises.
  • Locations with substantial and continuous heating load including hospitals, care homes and hotels.

Optional extras

  • Pipework kits to match the boiler model for ease of installation on site.
  • Flues available through our flue partner Jeremias UK
  • 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.

Single Boiler Controls

  • Outside air temperature sensor QAC34 (Part no. 533901457).
  • Domestic Hot Water sensor kit (sensor and pocket) (Part no. 563605674).
  • Mixing valve heating circuit control kit (clip in control module, temperature sensor and pocket) for 1 zone (Part no. 563605668).
  • Mixing valve heating circuit control kit (clip in control module, temperature sensor and pocket) for 2 zones (Part no. 563605669).
  • Mixing valve heating circuit control kit (clip in control module, temperature sensor and pocket) for 3 zones – Note: cannot be used in conjunction with volt free contact kit (Part no. 563605670).
  • 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).
  • Volt free contact kit for remote status signalling AGU2.550A109 (Part no. 563605666).
  • Heating circuit sensor kit (sensor and pocket) QAZ36 (Part no. 563605673).
  • Merley boiler sequence controller, wall mounted (Part no. 563605672).
  • Merley boiler sequence controller, loose kit for panel mounting (Part no. 563605671).
  • LPB Bus communication module OCI345, one required per boiler module (Part no. 563605667).
  • Programmable room sensor QAA75 (Part no. 533901587).

Often bought with

Chesil pressurisation unit

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Burstock expansion vessel

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Powerstock glass lined calorifier

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Merley boiler sequence controller

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Case studies

The Baglioni Hotel is a 5-star luxury hotel in London.

Baglioni Hotel

Sector: Hotel

Project: The luxury 5-star hotel was in need of a replacement for its old Wessex County boilers and turned to Hamworthy for a replacement. Together with JCS and Midtherm Engineering, Hamworthy delivered a space-saving solution for the tight hotel plant room.

Building: Hotel plant room refurbishment

Application: Space heating 1,176kW, DHW

Learn more
St Paul's Cathedral benefits from Hamworthy's Wessex ModuMax modular boilers' efficiency and quick heat up time.

St Paul's Cathedral, London

Sector: Historic building

Project: The prestigious cathedral on the top of Ludgate Hill benefits from modular boilers and high-performance calorifiers from Hamworthy Heating.

Building: Grade 1 listed refurbishment

Application: Space heating 1,016kW, domestic hot water 1,000L

Learn more
The Welcombe Hotel in Stratford-upon-Avon benefits from a range of Hamworthy products.

Welcombe Hotel

Sector: Hotel

Project: Danny Bulch from Cedar Green selected a variety of Hamworthy products to suit different applications at the Hallmark Welcombe Hotel.

Building: Hotel plant room refurbishment

Application: Space heating 540kW/588kW/154kW; DHW 2,149 L/h

Learn more
The Langham Hotel chose compact modular boilers for their rooftop plant room.

Langham Hotel, London

Sector: Hotel

Project: The prestigious Langham Hotel in London needed a high performance, lightweight hotel boiler for their rooftop plant room. See how Wessex ModuMax modular boilers provide the best solution.

Building: Hotel boiler plant room refurbishment

Application: Space heating 6,750kW, domestic hot water

Learn more
Stanmore Place benefits from an expandable and space-saving modular boiler solution  from Hamworthy.

Stanmore Place, London

Sector: Residential and commercial, community heating

Project: This award-winning development chose Wessex ModuMax boilers to save space and match the requirements of their district heating network.

Building: Flagship development of apartments, houses and offices

Application: Space heating 7900kW, domestic hot water

Learn more
Hamworthy hotel boilers with 10 bar reach the pressures required for the Danubius Hotel

Danubius Hotel

Sector: Hotel and Leisure

Project: A busy hotel in London was looking for a boiler upgrade. Contractor SPIE UK worked with Hamworthy to find a hotel boiler that can deliver the working pressure required for the high-rise building.

Building: Hotel plant room refurbishment

Application: Space heating 3,048kW, DHW

Learn more