With so many different types of commercial boilers to choose from, it’s important you understand what a modular boiler is and what benefits a cascade boiler installation may bring. In this blog, Ideal Commercial offers advice on when and why to choose a modular boiler.
With environmental and financial demands on heating and hot water systems ever increasing, Building Services Engineers are turning more and more to modular boilers as a solution. This is especially true in buildings where demand can vary widely every day.
What Is a Modular Boiler?
Essentially comprising of a number of separate boilers working together, modular boilers can provide great power with great efficiency. This is achieved by sharing modulation across all modules, preventing the inefficiencies of on/off cycling often found in singular boilers.
Modular boilers offer optimum performance, efficiency and reliability - ideal for commercial properties.
What Is Modulation?
Modulation is the boiler’s ability to reduce its output depending on the heating needs of the building. The rate of modulation is determined by the ratio between a boiler’s maximum and minimum output; the bigger the modulation rate the better, because there’s less likelihood the boiler will need to stop and start to provide the right level of heat required.
Modulation prevents boilers from cycling on and off, helping to improve fuel efficiency and boiler longevity. By matching the output power to the thermal load of the system, a modulating burner can manage the return flow temperature, which is key to boiler efficiency. A higher modulation ratio means the system won’t constantly switch on and off when the required level of heat is achieved; it will be able to modulate down to a lower output instead.
What Are The Main Benefits of a Commercial Modular Boiler?
Modular boilers offer a number of advantages when it comes to heating commercial premises.
1. Improved Boiler Efficiency
Many factors combine to create the impressive efficiencies today’s modern condensing boilers are capable of delivering, but modulation plays a crucial role in helping the boiler meet the demand placed on it at any given time as efficiently as possible.
Cascade boiler systems allow each boiler to modulate up until the demand requires output from a further unit, and so on until the demand is met. Work is shared equally between the units in operation, meaning each boiler can operate at its optimum efficiency.
When a single appliance is trying to provide heat to a large area it may regularly cycle on and off as demand changes, placing unnecessary stress on the heating system. A modular system allows multiple appliances to share the workload, thus reducing the reliance and wear and tear on one single boiler - making a modular system more reliable, efficient and long-lasting.
Put in simple terms - with separate boilers working together, you’re able to get the most out of all of them.
2. Greater Modulation Rate
According to the EUA, modulation refers to a boiler’s ability ‘to reduce its maximum output to its minimum output, in line with system demand’. In a commercial scenario, we all know that demand can vary dramatically and unpredictably.
Commercial boilers usually offer a modulation rate that provides increased control over the supply of heat that’s needed to meet demand, offering system benefits in terms of efficiency and longevity.
A modular setup of five 100kW boilers arranged in a cascade will provide the same output as a single 500kW unit - however it will provide an even greater modulation rate because there’s a greater maximum collective output, meaning the modulation ratio is increased. A greater modulation rate means there’s less need for each individual boiler to cycle on and off, which saves energy and reduces wear and tear over time.
3. Reduced Downtime
Another consideration in a commercial application is downtime. No one enjoys being without heat and hot water for any period of time, but in many commercial applications, downtime – whether for routine maintenance or due to mechanical breakdown – can be disruptive, expensive, and even damaging to reputation or health.
In the unlikely event of one of the boilers in the system failing, a modular boiler will ensure the system as a whole remains in operation. When it comes to routine maintenance, each boiler can also be taken offline independently of the others, again allowing for continuation of supply. This makes modular boilers perfect for commercial applications as it dramatically reduces the risk of your commercial building being without heart or hot water.
Why Choose a Commercial Modular Boiler?
While the benefits of a modular boiler apply to both commercial and domestic boilers, modulation can be particularly beneficial to commercial installations.
Commercial systems typically have to cope with a far greater spread of demand than the average domestic system. Domestic systems typically only require an ability to adjust outputs according to the external temperature and comparatively predictable demands from a handful of users. Lower modulation rates of up to 5:1 are almost always adequate for domestic systems, so a modular boiler is not always necessary.
In commercial applications, where demand can fluctuate dramatically, a higher modulation rate allows efficiency to be maintained. In many commercial scenarios, modular boilers provide the best solution.
Modular Boiler Case Study: Hitard Court Introduces the Ideal Commercial Evomod
About Hitard Court
Hitard Court in Southwark, London, was built in 2012 as part of the first phase of the Aylesbury Estate regeneration. The building has a District Heat Network with boilers in the basement plant room generating hot water which is then pumped around the building. Heat Interface Units are used to provide hot water and heating to each apartment.
About The New Installation
Unfortunately, the original boilers failed, so the capital plant boilers needed to be replaced… and quickly. With over 400 residents at risk of having no heating and no hot water, East West Connect Ltd turned to Ideal Commercial to help provide a solution quickly to make sure hot water kept flowing.
Why Did Hitard Court Choose Evomod?
The choice of boiler depended on two main factors:
- The boiler solution needed to have a high rate of modulation, as the demand from residents varies widely throughout the day. The boiler system also needed to have a high enough output to cope with peak times.
- The physical size of the boiler had to be considered. Not only did the boiler chosen have to fit in the available space in the plant room, there were also stairs to negotiate to get into the plant room.
Following site visits with his local Ideal Commercial contact, Ross Carroll, Projects Director for East West Connect, decided on an Evomod 1MW boiler as the answer for Hitard Court. The Evomod modular boiler is comprised of stackable modules each offering a 250kW output, making it a scalable commercial heating solution which can be increased to meet specifications of up to 1MW.
The Evomod hit every requirement of the brief. Each module has a modulation rate of 5:1, meaning that four combined gives a 20:1 modulation rate. This in turn allows the boiler to modulate down to just 46.7kW from its high maximum output.
The Evomod provides flexibility in not only performance, but installation too. Four separate modules were easy to transport into the plant room and, when bolted together, the boiler has a footprint of less than 2m2. This meant the Evomod could comfortably fit into the space available.
A Satisfied Commercial Customer
East West Connect site manager Peter Cowan, who was responsible for the installation, said: “The installation of the Evomod boiler was a quick and easy process. We were able to run our own pipework away from the boiler easily as it came supplied with a manifold and the right pipe connections.”
Ross Carroll, Projects Director for East West Connect, was more than happy with the end result. He said: “I would recommend Ideal Commercial to the industry as they are always with you from conception to completion, from sales through to technical, through to commissioning.”
Modular Boiler Case Study: New Build Installation at Newton Mearns, Glasgow
A Modular Boiler Choice For A New Build Project
Faith Schools' Joint Campus in Newton Mearns, Glasgow, replaced an existing Jewish school and provided additional primary school provision for the local Catholic community. The building boasts a shared amphitheatre and outdoor obstacle trails, as well as sports pitches, first-class ICT facilities, modern teaching spaces, an impressive library and state of the art science laboratories. The large, complex new building was part of a £18.2million project, and it was important the campus had a suitable heating system to meet its needs.
Why Did Newton Mearns Choose Ideal Commercial?
Ideal Commercial was selected from a tender panel of manufacturers to provide a high output boiler solution capable of delivering 1.5MW in an unusually small footprint. Boasting stainless steel heat exchangers, two 3-module Evomod boilers were installed using a combined flue header for all three modules of each boiler. Each provides an output of 750kW, and comes complete with flow return pipework for quick installation.
Achieving Great Results With Evomax
Christopher McCall, Operations Director of Marmac Services Ltd, who carried out the installation, said: “Working closely with main contractor Heron Bros we were able to install the Evomod system quickly and efficiently, with no delays caused to other onsite trades. Being of modular design, the boiler was easier to install in the tight spaces available during the later stages of the project.”
“Like all Ideal Commercial boiler systems, costing the specified products was straightforward, with the merchant able to assist in the specification process. I have worked with Ideal Commercial in the past and had nothing but positive results.”
Boost Your Commercial Boiler’s Efficiency
A boiler’s modulation rate has a significant influence on its ability to operate at its most efficient point. As modular boilers offer the opportunity to provide the same output and the potential for a greater modulation rate than boilers that are working independently, a cascade system could be the way to go for your next installation.
Get in touch with our Ideal Commercial experts to find out if a modular boiler would best suit your needs.
Notes: versions of this article first appeared in HVR magazine, March 2017, BSEE magazine, April 2019 and MBS magazine, April 2019.
