commercial gas boilers; commercial lpg boiler; wall hung gas commercial boilers; commercial boilers in cascade; Worcester; price; vat; job;Flexiheat UK

Commercial gas boilers – 50kW to 960kW

commercial gas boilers; commercial lpg boiler; wall hung gas commercial boiler; commercial boiler in cascade; Worcester; price; vat; job;


Commercial Gas Boilers – Available from 50kW to 120kW as single Boilers or up to 960kW in a cascade configuration. Commercial boilers work in exactly the same way as domestic boilers, but are designed and manufactured to efficiently cope with the higher hot water and heating demands of a commercial premises or business.

Energy efficient commercial boilers

These highly efficient commercial boilers are available in both Natural Gas and LPG, and with various models with an output range from 50 kW to 120 kW, in a wall hung or floor mounted when mounted on our free standing frame kits configuration. Making them the ideal boilers for any commercial premises or commercial business.

These commercial boilers work in a fully modulating range, which provides energy saving through 1:10 modulating operation for 50kW and 60kW models

50kW and 60kW gas condensing boiler; lodge; vaillant;vat;collect;vat;job;price

50kW and 60kW gas condensing boiler from Flexiheat UK


and 1:20 for models 75kW, 100kW and 120kW. As the larger units have 2 heat exchangers within the one casing, should one unit fail, you have 50% of your heat requirement still operational. You can also service one of the units when the other is still operational- so your heating system is never down .This is an important feature and benefit for these units.

75kW to 120kW output gas condensing boiler from Flexiheat UK; vat; job; price;

75kW-120kW gas condensing boilers from Flexiheat UK


These gas condensing boilers can be installed directly on the wall thanks to their reduced size and low weight, freeing up valuable space inside the boiler house of your commercial property or business.

These are modular boilers, and can be coupled together in a commercial gas boiler cascade configuration which you can think of as multiple boilers within “One Total Boiler” as such, this give this range of commercial boilers , a few distinct advantages when compared to others, in that – If one system boiler goes down or malfunctions, you still having the remaining modules to provide you with heat, thus increasing reliability , which can be vital in applications like nursing homes, hospitals etc.

Furthermore, multiple boilers, when in a cascaded configuration have power control boards that communicate between them and handle the power output of every module in a uniform and coordinated way in order to guarantee the maximum efficiency, matched to the heating requirement of the installation.

The performance of this commercial boiler range with a wide range of power outputs makes it one of the best gas condensing boilers to use in any commercial boiler installations, be it feeding radiators, radiant panels, fan-coils, underfloor heating etc and to install in any boiler house, in either new or when replacing existing units in any buildings, houses, hotels, schools, factories, or any other industry etc.

With low class leading NOx Class 6 levels for all this brand ensuring maximum BREEAM points, which is important for any UK business interest, and something to be expected from leading manufacturers at this date


  • INNOVATIVE DESIGN, COMPACT, POWERFUL, & LIGHTWEIGHT – The devices have been developed and manufactured to be “space-saving”; thanks to their vertical structure they allow space savings in both new installs and to upgrade or replace older failed units or replacing an oil fired system boiler ( or even steam). Due to their light weight they are easy to carry , place and mount. Thus easy to install.
  • Stainless Steel condensing boilers that optimizes the output according to real thermal needs of the installation and business, ensuring maximum efficiency with a working pressure of up to 3 Bar
  • WIDE MODULATION OR TURN DOWN RATIO -wide modulation or turn-down ratio of 1:10 for the 50kW and 60kW and 1:20 for the 75kW, 100kW and 120kW units and up to an incredible 1:160 in cascaded configuration installation of 960 kW for example.
  • STAINLESS STEEL HEAT EXCHANGERS -Each heat exchanger is made without weld joints and is 28mm diameter in size with a industry standard working pressure of 3 bar.
  • ECOLOGIC PREMIX BURNER -The whole range of boilers is equipped with ecologic premix burners made of Fecralloy metal fibre.
  • This range of condensing commercial boilers are suitable for use on sealed systems and open vented installations ( with a minimum of 0.3 Bar Head) and perfect for both new and retrofit installations.
  • We also do a combi version, which is listed here on our website here-

Commercial combi boilers up to 100kW or a dedicated webpage for our most popular 50kW combi boiler

Why choose our Commercial Natural Gas Boilers –

High efficiency and fuel savings at the right price solution for your business

Condensing Boiler Technology

Total flame modulation

Certified efficiency up to 109%

Cascaded sequence control and heat exchangers in rotation – a solution for industrial applications


Quiet in operation

Easy installation and maintenance – in the rare occurrence of a breakdown – access to all essential system components

Reduced size and weight

Construction Quality

Modern, innovative and attractive design to keep your customers happy

large water ways the range benefit from a stainless steel heat exchanger, with industry leading dimensions

Turn down ratio up to 1:20

Ecology / Ecological

Fecralloy fibre premix burner

Reduced gas emissions in the atmosphere

Low CO and NOx levels – Class 6 -industry leading

Wall Hung Gas Boilers – Commercial / Industrial

The 50kw to 120kW Output Commercial Boilers. The R1K Range of commercial boilers , which benefit from high efficiency with premix condensing technology. The technical details of these units are –

50kW to 75kW units

50kw to 75kW gas fired boiler technical data from Flexiheat UK; job;

50kw to 75kW gas fired boiler technical data from Flexiheat UK; job;

100kW & 120kW units

100kw and 120kw boiler technical data from Flexiheat UK

100kw and 120kw boiler technical data 2 from Flexiheat UK



For the complete technical data on our range to suit your site services, be it Natural Gas or LPG , Please click on the following –

Download Flexiheat R1K Internal 50-120kw gas fired condensing commercial boiler manual

Boiler Control Options

All units can be controlled by an “OpenTherm” compatible controller or we can supply a 0-10 Volt connection kit suitable for BMS connection.

Commercial boiler installations in cascade natural gas or LPG

These commercial Gas Boilers can be used in a cascade configuration of up to 8 boilers , with the potential of 960 kW of heat output  , making them the ideal boilers for Schools , Hospitals , Hotels, or any Commercial or Industrial site that requires heating via a hot water system. With a turn-down ratio of up to 1:160, these commercial boilers are the best option when you want to match your heating load, at the very best efficiency levels , giving you the lowest gas costs / gas usage for your business.

commercial and industrial gas boiler; commercial boiler in a cascade;commercial boiler installations

Commercial gas fired boilers in cascade from Flexiheat UK up to 960kW of output

Commercial Boilers for sale UK and Ireland

To ensure you get the correct commercial gas boiler in either natural gas or LPG, that is right for your business or application, our sales team are here to provide information and advice to help you make an informed decision for your project factors . With high operational reliability that you would expect from a leading brand that you as a customer can rely on, please 01202 822221 to be transferred or connect to our sales team or use our website contact form, to get the latest offers and price.