Chiller Maintenance Tips for Winter Operation.

Low temperatures and harsh winter conditions put your chillers and HVAC equipment under added pressure, particularly if they’re located outdoors as many large commercial chillers are.

When the ambient temperature drops, the water in your chilled water system can contract by up to 9% in volume. This potentially can cause a breakdown with a significant amount of damage to components and pipework.

With so many commercial businesses entering their busiest time of the year, we’ve created some chiller maintenance tips for winter operation that you can take to help keep your chillers and cooling equipment running efficiently so you can avoid downtime and keep your business operating smoothly through the winter!

Have you maintained the correct Glycol levels?

By dosing your system with the correct level of glycol and maintaining this, you will prevent the water from freezing and causing damage to your system which minimises the risk of downtime and cost to your operation.

Glycol chillers are industrial refrigeration systems that use a type of antifreeze called glycol, mixed with water, to lower the freezing point in the application of the chilling system.

Glycol is a class of organic compounds that belong to the alcohol family. When mixed with water and pumped through the pipes of a chilling system, glycol serves to slow the rate of freezing. It helps maintain temperature consistency in the application.

Most glycols these days also contain biocides and inhibitors that are essential for your systems continued health. Drops in this can cause bacterial blooms or electrolytic action which can strip aluminium and copper from your system.

Rapid temperature drops can cause the water in your chilled water circuit to freeze quickly if it has not been dosed correctly with glycol. This can result in expansion which can lead to fractured pipework or at worst, burst pipes.

To learn more about how a glycol chiller works or to find out if this system is right for your application, contact the team today!

Have you checked the trace heating?

In simple terms, a heat trace system is where electrical cables or other heating elements are wrapped around the pipes or vessels supplying heat energy that is used to maintain or raise the temperature wherever required. Not only freezing, but heat trace also prevents heat loss from the pipe and helps maintain the temperature wherever required.

Your chiller pipework may be protected from freezing with trace heating tape. If so, visually check the tape for any corrosion or damage, including any connections, to ensure it continues to protect your pipework.

Due to the nature of this task, it would be advisable to get our Service Engineers to carry out more in-depth checks and analysis, so that any fixes can be made safely, with the correct equipment to hand.


Check for blocked strainers.

Your chiller’s strainer protects the pumps, heat exchangers and all other vital components from particles or contaminants.

Strainers can easily become blocked by scale, corrosion, biofilm, weld slag, dirt, iron oxides, and suspended solids. When the strainer is blocked, it can lead to pipe blockages, failed pumps and then potentially make them susceptible to freezing issues.

Try cleaning coils and condenser fans.

Winter conditions can cause condenser coils and fans to work even harder!

By keeping them free from debris such as autumn leaves and dirt, you will help to increase the efficiency of your chiller system and thereby reducing your operating costs. A blocked condenser will inhibit the rejection of heat, and a dirty coil can reduce airflow drastically.

For each 10% reduction in airflow, the efficiency of the chiller drops by about 20%. If your chiller is fitted with a free cooling system, this will reduce the performance and therefore increase your energy costs.

Energy costs, especially for commercial buildings, are essential to be on top of and anything little things such as keeping systems clean and clear of dirt is vital.

Our Planned and Preventative Maintenance.

Not only are chiller maintenance tips for winter operation important to understand but chilled water systems require regular maintenance checks and servicing to keep them running smoothly and efficiently.

Mid-Tech Services provide award-winning Planned and Preventative Maintenance programs, tailored to your business and operation. Our highly qualified, dedicated engineers get to know you, your business and facilities inside out, enabling them to provide a personal, consistent and exceptional standard of service.

We have been supporting well-known commercial sites such as Iceland Foods and the Tate Galleries with maintenance and have massively impacted their energy operation.

To discuss how we can help improve the efficiency and maintenance of your chilled water systems, please get in touch with our team!

Or if you are searching for a renewable system to heat and cool your commercial space this winter, check out our specialised team at for all the information.