Get peak performance from your hydronic boiler

Thursday, 17th June 2021

Set up your boiler for success from the start to avoid a myriad of costly replacements down the line and to ensure the best possible long-term performance. 

If you’re considering installing a hydronic heating boiler into your latest development project, there are a few factors you’ll want to take into account to maximise its lifespan and efficiency. Ultimately, the keys to getting the highest level of functionality from your boiler are:

  • protection
  • separation
  • treatment.

The team at Hunt Heating Commercial can help you determine the best approach for your project, but here’s an overview of the key factors to consider.

Prioritise Protection and Separation

When planning and preparing for any hydronic boiler installation, it’s important to consider the overall system you will be installing it within. For example, it would be entirely counterproductive to install the best hydronic heating boiler into an old system with accumulated sludge and dirt. More times than not, older systems will have a build-up of debris, often as a result of oxygenation.

Contamination such as limescale, system dirt and magnetite within the boiler heat exchanger waterways can result in residue on the heat exchange surfaces, which can then reduce the capacity for heat exchange. Anything that creates resistance to system flow is likely to affect the boiler performance. 

Fundamentally you want to protect the internal elements of the boiler from corrosion and to prevent the growth and build-up of any pollutants so the boiler can effectively and efficiently do its job.

Hydronic heating boilers have been used across Europe for years, but as they are relatively new to the Australian market, there is less chance that you will be doing a retrofit of a new boiler to an older open vented system. Regardless, you still want to avoid pollutants accumulating in your water-based heating system. 

This challenge can be solved by using separation equipment. Air, dirt or combined air and dirt separators divide the smallest dirt particles or micro air bubbles. 

Methods of protection and separation

commercial hydronic boiler, hydronic boiler supplierBy using appropriate system protection and separation methods for your hydronic boiler you will be able to increase the longevity of the overall set up. 

There are a number of approaches and methods that you can use to protect the boiler from pollutant build up including:

  • Filters or strainers
  • Air and dirt separators
  • Low loss headers
  • Magnetic low loss headers
  • Plate heat exchangers

Below is a high level overview of two common approaches:

Air and dirt separators

Both solid particles and air can be separated from your boiler system water using a combination of:

  • coalescence
  • reduction of the flow speed
  • pressure reduction.


Under the influence of coalescence, micro bubbles attach themselves to metal and other surfaces; lowering the flow speed of system water allows air bubbles to rise and a drop in pressure releases gas dissolved in fluid. The combination of these three technologies alongside optimal system flow guarantee the best possible performance from your system set-up. 

Plate heat exchangers

First produced in the 1920s, plate heat exchangers are another popular option for system separation. This method works by transferring heat from the boiler circuit to the system circuit without the two coming into direct contact.

A series of plates placed one against the other create channels for the water to run between them, while the heat is simultaneously being transferred through the plates. There are two varieties of exchangers – gasketed and brazed - the first is a series of plates fitted with elastomeric gasket within a frame, while the brazed exchanger doesn’t include gasketed joints and enables higher temperatures and design pressures. 

Water treatment – a vital factor

Once you have established which options you will choose for boiler protection and separation, it is important that you consider your approach to the treatment and ongoing maintenance of the quality of water that will run through the boiler and system circuits. 

The system is initially filled with fresh, untreated water. This water can contain oxygen and other compounds, which needs to be treated to minimise corrosion of the internal boiler and system parts and prevent mineral scale forming and building up and hold off the growth of microbiological organisms. 

Regardless of whether you are installing the best hydronic heating boiler into a brand-new system, or you are doing a retrofit of a new boiler into an older system, a water-treatment program is required. Neglecting this step in the set up and maintenance can result in cutting the estimated life cycle of your boiler in half - a significant reduction in efficiency and unit lifespan and a waste of time and money. Ensure the correct water treatment is implemented from the beginning. 

heating boiler, commercial boiler

The type of water treatment program you will need for your boiler and system will vary depending on the components you are working with. This is due to the variety of materials your boiler and system are comprised of and the chemicals needed to address the specific circumstances of your set up.

Getting in touch with a qualified water treatment expert is advised so you can be assured that the appropriate chemicals in the correct concentrations are used for your system.

Contact our team of experts to discuss which options meet your project needs

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