Commercial heating and hot water knowledge articles
Here you can explore our articles about some of the key topics in commercial heating, hot water, legislation and energy efficiency.
You can use the filter below to find out more about a specific topic.
Hydrogen - one gas grid, many products
Managing the risk of legionella in domestic hot water systems
This Hamworthy article and video shows how legionella protection cycle works with a commercial direct fired water heater.
UK Hydrogen Strategy: What does it tell us?
The Government’s long awaited UK Hydrogen Strategy was released in August 2021 and is very much a top-level strategy addressing infrastructure and development of a hydrogen economy in the UK. We take a look at what it did tell us.
No flow boilers – application and installation
No flow boilers don’t depend on the system circuit flow for safe operation. But how does a no flow boiler work? Understand the application and installation of no flow boilers for cost effective heating system design.
Primary circuit or boiler shunt pumps in commercial heating
A question we get asked a lot at our CPD seminars is: ‘Which is best - a boiler shunt pump or primary circulation pump?’ There's no correct method, as long as the minimum flow is always maintained. And it will always depend on the project. In this article, we’ll look at the different pump options and their pros and cons.
Hydrogen as a fuel source explained
Hydrogen gas as a low carbon fuel source is currently a hot topic that will continue to be so for the coming decade. We take a look at what Hydrogen is, how it’s produced, and when it may be used to heat our homes and buildings in the future.
Refurb or replace – what to consider when upgrading your commercial heating system
What to consider when you are refurbishing your plant room. Understand your heating and hot water replacement options.
What are expansion vessels for unvented kits?
Understand expansion vessels for unvented kits, for use in an unvented hot water system, including flow jet valves. More about the benefits, including legionella prevention.
What is an Unvented Kit?
Understand unvented hot water systems, closed systems and discover what is included in an unvented kit
How to size a low loss header
Understand how to size a low loss header to maximise efficiency in residential and commercial heating systems
What is a low loss header? And when to use one.
Understand low loss headers and hydraulic separation, when to use a low loss header, and their benefits and disadvantages.
Indirect Hot Water Cylinders and Storage Tanks
What is an indirect water cylinder or tank? Exploring calorifiers and indirect fired hot water cylinders and tanks, their features and benefits.
Direct Hot Water Systems
What is a direct fired hot water system, how does it work and what is it used for? Exploring direct fired water heaters and integral gas or oil burners, and their features and benefits.
How does a calorifier work?
Find out how a calorifier, or indirect fired hot water cylinder, works as part of an indirect fired hot water system.
Temporary boiler plant rooms
Temporary boiler plant rooms can overcome issues when refurbishing old plant to guarantee an uninterrupted heating and hot water supply.
Stratification in water heaters
Stratification in water heaters can be problematic. We explain what causes it and how it can be avoided to prevent the growth of Legionella bacteria.
Hydraulic separation in heating systems
When it comes to refurbishments, it is important to protect new equipment. This can be done by hydraulically separating the primary and secondary circuit. We look at different methods to achieve this.
Medium Combustion Plant Directive in commercial heating
The Medium Combustion Plant Directive came into force in 2018 and regulates sulphur oxide and nitrogen oxide emissisions as well as dust into the air from combustion plants. In this article, we look at the MCPD specifically in reference to commercial boiler plants.
NOx emissions from commercial boilers
NOx emissions are the 'hot topic' of the industry. In this article, we investigate why they are a reason for concern, how they are generated and what we can do to reduce them.
Efficient heating system design with built-in boiler controls
An often overlooked aspect of energy efficiency is correct monitoring of external factors which influence the temperature in a building, understanding the usage of premises and how to set up boiler controls correctly. We look how these can assist to set up an efficient heating system.
Cleaner Heat Cashback
The Government has introduced a commercial boiler scrappage scheme for London to cut carbon and NOx emissions in the capital to improve air quality and energy efficiency in non-domestic buildings. We take a look at the criteria for a replacement, how the application works and how you can become a Hamworthy-approved installer.
Driving condensing boiler efficiency
In 2015, we saw the introduction of the Energy-related Products Directive. What is the aim of this legislation and what impact does it have on the commercial heating and hot water market?
ErP Energy Labelling
Energy labels indicating energy efficiency were introduced in 2015 to be applied to consumer products. A part of our product range is also affected.
ErP Directive for water heaters
The ErP Directive does not only affect boilers but also water heaters. The requirements are not limited to energy efficiency and noise levels. Read our article to find out more.
The Energy-related Products Directive was one of the major legislations which has almost eradicated atmospheric boilers from the market. Learn more about the directive and its requirements here.
Corrosion protection for water tanks water heaters
Protecting your water heater is essential to ensure a continous hot water supply without breakdown. What are the available means to protect water heaters from corrosion? We've compiled information for you in this article.
What is a calorifier?
Ever wondered what exactly a calorifier is? We explain how a calorifier works and what it's used for in heating and hot water systems.
Sizing hot water systems for sports facilities
Sizing hot water systems is a science in itself. Getting it right means you have a sufficient hot water supply without the risk of paying more for hot water you don't need. Find out more in our article.
Condition Improvement Fund
Looking to fund your school boiler refurbishment? The Condition Improvement Fund could be right for you. Learn more about how it works, who is eligible and what projects can be funded.
Minimum Energy Efficiency Standards
Non-domestic private rented properties are required to meet a minimum threshold when it comes to energy efficiency. This is regulated in the Minimum Energy Efficiency Standards which were enforced in the Energy Act in 2011. We have put together some information on this for you.
Over the last few years, the government has introduced legislation to achieve carbon savings targets. Do you know which legislation exists? Have a look at this page to learn about it and what's behind the acronyms.
Load matching in multiple boiler installations
The use of several small boilers compared to one big boiler can make your heating system a lot more efficient. How it works - learn more about the benefits of large turndown ratios and improved system efficiencies.
Energy Technology List
You can benefit from tax deductions if you decide to invest in energy saving heating equipment. The Energy Technology List tells you which products are eligible. Learn more about it and which products are eligible for Enhanced Capital Allowances.
Minimising heating plant size
Plant room space in the city is limited and expensive. What if you could minimise the size of your heating plant? We look at how modular boilers can achieve this.
Commercial boiler flue systems
How much do you know about different flue types? We have compiled this page for you to find out more about available flues and what they look like.
ErP-compliant cast iron boiler
Think the Energy-related Products Directive saw the end of cast iron boilers? Our cast iron boilers changed this, they can not only condense but are also ErP compliant. Find out how we've achieved this.
Open vented heating systems compared with sealed systems
Open vented boiler systems have been traditionally used. In modern times, sealed heating systems are the favourite choice. We look at differences between both and how to deal with them when refurbishing your heating system.
Modular boilers load matching in heat networks
How do you design a heat network to efficiently match peak and low heat loads? Find out how to create a high boiler turndown ratio for your modular boiler system
Modular boilers for heat networks
Modular boilers are a compact and flexible solution. In heat networks, they can provide an excellent back up and top up solution to support other equipment such as CHP. Learn more about why modular boilers are being used in district heating schemes.
Low loss headers explained
Why should you use a low loss header in your commercial heating system? We explain how it works and what benefits it can have for your heating system.
Life cycle costs of a heating system
When purchasing new equipment, there is always the question concerning upfront costs and running costs. In this article, we compare both of them and explain the advantages of looking at the long-term costs of heating equipment.
What are district heating networks
One of the Government's carbon-saving initiatives is the use of heat networks. What do they consist of and what benefits do they have?
Changing heating system design with wide temperature differentials
Wider temperature differentials are increasingly used to design commercial heating systems. We investigate how this affects heating system performance and what you need to understand when designing these systems.
Commissioning commercial boilers
Commissioning is an essential procedure to ensure your commercial boilers and/or water heaters have been correctly installed and setup. What does it involve and what other benefits does it offer?
Cast iron boilers
Cast iron is a material that has been used for a long time in commercial boilers. Learn how it has developed over time and why it is still a material of choice in the heat exchanger of our boilers.
Comparing direct and indirect fired water heaters
What is the difference between direct and indirect fired hot water systems? What does it depend on and whether I should choose one over the other? We shed light on this topic in this article.
Boiler heat exchanger for commercial heating
A wide variety of metal alloys are used in commercial boiler heat exchangers. Not every metal is suited for every application, that’s why we’re taking a look at the benefits of each material and for which kind of projects they are a popular choice.
Changing boilers from atmospheric to condensing
Refurbishing a commercial heating system can bring many challenges. In this article, we're looking at older heating systems and what needs to be considered when preparing them for a change from atmospheric boilers to condensing boilers.