Frost Coils

If you’re in charge of managing a facility or you own a building, there’s a critical scenario you absolutely want to avoid – the freezing and bursting of your HVAC coils. This unfortunate event doesn’t just result in decreased productivity; it could potentially lead to costly repairs or even the complete replacement of the coils. The good news is that there are things you can do to prevent the freezing of these important HVAC components. Within this blog, we’ll delve into the different reasons for coil freeze protection and explain the advantages and disadvantages of each approach. So, let’s dive in and ensure a cosy environment!

Crucial for maintaining a comfortable indoor environment, fluid and steam HVAC coils are susceptible to severe damage when exposed to freezing temperatures. The consequences of a ruptured coil can be extensive. As the coil thaws and tries to return to its system pressure, it could trigger flooding, thereby inviting equipment damage and necessitating mould and mildew remediation. Repairing or replacing the coil adds to the expenditure of both time and money. Facility operations coming to a halt can lead to financial losses and reduced productivity, all while leaving occupants dissatisfied. Additionally, should an insurance claim be initiated due to the aftermath of a ruptured coil, it could result in future premium increases. The combination of these factors underscores the importance for facility managers and building owners to proactively shield their HVAC coils from the perils of freezing temperatures.

Reasons why coils Freeze

The freezing of HVAC coils can be attributed to several underlying factors:

  1. Outdoor Air Damper Stuck Open: A malfunctioning outdoor air damper that remains open can permit cold outside air to enter, cooling the coil and paving the way for freezing.
  1. Stratification: When there’s an imbalance between return and outdoor air mixing, stratification may occur. This uneven mixture can cause certain sections of the coil to cool more than others, potentially resulting in freezing.
  1. Controls Malfunction: Faulty controls or incorrect settings can trigger coil freezing. This might arise from an inaccurate setpoint temperature, a malfunctioning economizer cycle, or glitches in the system’s control logic.
  1. Power Failure: During a power outage, the circulation pumps and air handling units (AHUs) cease operation, leaving coils exposed to frigid air and leading to freezing.
  1. Improperly Drained Coil: Even a small residual amount of fluid within a coil holds the potential to freeze. This can generate sufficient pressure to rupture the return bends of an HVAC coil.
  1. Human Error: Adjusting settings or operational modes intended for one season but not suitable for another can inadvertently result in frozen coils.

Understanding these factors and their potential consequences is paramount for effective HVAC coil maintenance.

Your HVAC system is a complex and valuable investment that plays a vital role in maintaining a comfortable indoor environment. Neglecting its maintenance can lead to a range of problems, with frost coil seizure being one of the most serious. By prioritizing regular HVAC servicing, you can prevent the nightmare scenario of burst coils and the subsequent damage it can cause to your property. Remember, a little maintenance today can save you from significant expenses and headaches down the road.

At Gibbons we carry out free inspections of HVAC systems, so you can replace any deteriorating equipment before it fails. Discover more about our range of HVAC services for commercial buildings by calling 01621 868 138 or email

2023-08-30T10:33:33+01:00HVAC Services|
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