What role can modular boilers play in improving the energy efficiency of a commercial building?

At Hamworthy we believe modular boiler systems present the most efficient choice for non-domestic buildings and have been pioneering the use of modular boilers since the 1960s. Want to know why? Book on to our Energy saving CPD to see how modular boiler systems reduce gas consumption and lower fuel bills.

What are modular boilers?

Modular boilers are designed as an alternative to large single boilers and offer a very efficient approach to commercial heating. Each module can be a separate boiler installed alongside another in a horizontal arrangement, or as a vertical stack of boiler modules one above another. 

How do modular boilers work?

Modular boilers provide a flexible and secure approach to heating solutions, with each boiler module providing a percentage of the total system load.

Commercial modular boilers

The advantages of modular boiler systems

Easier to install

Smaller modular boilers are physically easier to transport and handle than very large boilers. For retrofit projects they can be installed alongside the existing boiler as they are capable of high outputs from a compact size. Indeed, Hamworthy’s Upton vertically stacking condensing boiler range can provide more than 1MW output from 1 square metre floor space.

This enables a smooth changeover from the old heating system to new with little or no system downtime.  This makes the modular boiler system very popular in schoolshealth sector and hotels where continuous heating is critical to their business.

All Hamworthy modular boiler ranges have lightweight designs and will fit through a single doorway, making them ideal for roof top or basement plant rooms and high rise residential buildings.


Increase system security

In the event of a module breakdown the building can still be heated sufficiently by the other boilers in the system. The servicing of modular boilers is also much more convenient. Access to the boilers is usually easier and one module can be serviced whilst the others continue to meet the system demand for heat without the risk of interruption to services. 


Load matching and control

A benefit of modulating boilers installed in a modular boiler system is their ability to closely match the load profile of the building. A sequence controller installed in a multiple boiler system enables the modulating boilers to be operated in such a way that they modulate together to match the load. By firing the maximum number of boilers needed to match the load with each operating at or near its minimum modulation, each modulating boiler is operating in its most efficient state, i.e. part-load. This maintains very high system operating efficiency. Read more about load matching in a multiple boiler system.


Cost reduction and energy savings 

The ability to accurately control efficiencies of modular condensing boilers will ensure that these are the most sustainable and economic solution for many years to come. They have a significant role to play in carbon reduction and can produce real energy savings. 


Our Energy Saving CPD seminar has an example of a hospital that could achieve savings of more than £1.2 million on their gas bills over a 25 year life by opting for smaller output modular boilers over large output single steel boilers. This impressive cost saving comes mainly from the greater control and larger turndown ratios of the modular boiler system.

Wessex ModuMax mk3 modular boilers installed at listed building Upton House

Upton modular boiler

98-1,047kW output

Up to 15:1 turndown ratio

Packing power and efficiency into small spaces. With this modular boiler you can get 1MW output from 1 squared metre footprint - ideal for city centre projects.

Discover the Upton boiler here.

Wessex modular boiler

97-762kW output

40°C differential temperature and 10 bar working pressure

Built on tradition, designed for modern requirements. Discover the Wessex ModuMax modular boiler here.

Wessex ModuMax mk3 modular condensing boiler have achieved almost 40% gas savings at St Paul's Cathedral.