As buildings restart after the Christmas and New Year break, HVAC systems are pushed to perform at their best during the coldest part of the year. While attention often focuses on heating demand and energy use, the condition of the water inside these systems is easily overlooked. Reduced operation during the holiday period can leave lasting water-side issues that impact efficiency, reliability, and comfort just when systems are needed most. This article explores why water treatment matters in January and how the right approach can protect performance throughout winter and beyond.
Don’t Let the Cold Outside Lead to System Trouble Inside
As buildings come back to life after the Christmas and New Year break, the pressure is on HVAC systems as they ramp up to meet the requirements of the winter heating season. January is typically one of the coldest months of the year, and heating systems are expected to operate at full capacity – just as facilities teams return to a backlog of reactive tasks and maintenance priorities. But while many commercial buildings will now be ramping up their HVAC operations as occupants return to the office, school or university, the quieter holiday period that preceded it may have left systems more vulnerable than expected.
With occupancy reduced, heating loads lowered, and plant running in setback modes or reduced schedules to save energy, water circulation will have dropped off. This increases the risk of sediment build-up and the potential for corrosion and bacterial growth in lower flow areas and stagnating pockets. In systems already experiencing poorer water qualities, even relatively short periods of reduced system activity can have lasting effects.
When building systems are brought back to full operation in the New Year, any water-side issues that developed during the break can quickly translate into flow restrictions, inefficient heat transfer or unexpected and unwanted plant failures. That means increased call-outs, discomfort for returning occupants, and higher energy use at exactly the time when budgets and operators are under strain.
These risks make January a key moment for reviewing your options for water treatment, not just as an immediate step to protect heating performance when buildings need it most, but also as a long-term energy efficiency measure. With FM teams busier than ever, having an automated water treatment system really makes sense, since they can operate in the background with minimal interaction required.
Chemical Free Water Treatment
Enwa’s EnwaMatic side stream units have been designed with exactly this issue in mind. Our units work continuously, removing suspended solids, regulating key water parameters such as pH, alkalinity and hardness in your heating systems, providing effective corrosion inhibition and scale control with minimal manual input.
Unlike chemical-based systems, EnwaMatic units don’t require on-site storage of treatment agents or manual dosing of chemical inhibitors. Many of our clients tell us that being greener and chemical free is one of the key benefits of Enwa’s technology.
What’s more, the fully-automated backwash cycle reduces the risk of human error and keeps maintenance demands low. As soon as the unit is installed, it quietly and consistently improves water quality, allowing HVAC systems to run more smoothly, efficiently and reliably.
Immediate Results, Long-Term Impact
For buildings with immediate water quality problems, Enwa’s side stream filtration starts making a difference from day one. As soon as it’s connected to the system, it begins to remove contaminants and improve water quality. That’s particularly valuable for systems showing signs of water-side degradation, such as elevated suspended solids, blockages or underperforming heating zones.
It’s also a highly adaptable approach. EnwaMatic side stream units can be retrofitted easily into existing systems, even while they remain operational. Utilising existing connection points where possible, or units can be ‘hot tapped’ for quick non-invasive installation. This makes it possible to upgrade water treatment without shutting down plant or disrupting service – a critical advantage during peak heating season.
Time to Rethink Water Treatment for 2026
With the coldest weeks still ahead, January is a smart time to act, both to secure short-term performance and to lay the groundwork for better building efficiency over the year ahead. Facilities and estates teams reviewing performance targets for 2026 should consider whether existing water treatment regimes are easy to manage and really delivering the results needed.
Enwa’s side stream filtration and water treatment units offer a low-disruption, high-return upgrade that help systems bounce back from seasonal downtime and operate at their best throughout winter. It also supports decarbonisation goals by ensuring energy isn’t wasted through poor heat transfer or overworked equipment.
Act Now
In the months ahead, many building operators will be watching energy use, heating reliability and tenant comfort more closely than ever. Investing in better water quality now can make a measurable difference in all three.
With its automated operation, ease of installation and proven performance, the EnwaMatic side stream filtration system is a practical, preventative solution that supports facilities teams when they need it most. Whether your heating system has returned from the break at full throttle, or is showing signs of strain, this is the moment to act.
Get in touch with us to learn more about EnwaMatic and our approach to water treatment and this important issue.
Hampus Mattsson
Sales EnwaMatic
+46 (0)76 139 04 33
hampus.mattsson@enwa.com
