When temperatures drop, most air conditioners are switched off for months. But without proper preparation, exposure to cold, moisture, and debris can lead to internal damage, rust, or system failure.
If your system sits inactive through winter, small issues often grow unnoticed. Dirt in the outdoor unit traps moisture. Pipes and coils exposed to cold may crack. Filters left unchanged allow dust to settle and clog airflow. These problems reduce cooling performance when summer returns and lead to costly repairs.
Taking a few simple steps before winter protects your investment and keeps the system ready for the next season.
Clean and Inspect the Outdoor Unit
Start with a thorough inspection of the outdoor unit. Power off the system and remove any built-up debris around the base and inside the grille. Leaves, twigs, and dirt trap moisture and restrict airflow. Use a soft brush or low-pressure hose to clean the fins and base. Avoid sharp tools or pressure washers that could bend coil fins.
Look for signs of damage. Cracked panels, rust patches, and loose screws should be addressed before further weather exposure. Damaged fan blades, warped casing, or blocked drain openings reduce performance and may cause the system to fail when restarted.
Cover the Outdoor Unit (If Appropriate)
Once clean and dry, cover the outdoor unit with a breathable protective cover. Avoid plastic tarps or waterproof materials that trap moisture — this creates ideal conditions for mould and corrosion.
Covers should allow air to pass through and prevent snow, leaves, or nesting insects from entering the fan housing. Mark the unit clearly so the cover is removed before switching the system back on in warmer months.
Insulate Any Exposed Pipes and Ducts
Check all visible refrigerant lines and ductwork around the outdoor system. Insulation that has degraded, split, or come loose should be replaced.
Use UV-stable foam pipe insulation for exposed lines. This helps prevent freezing, cracking, or heat loss through the line set. In areas where pipes pass through walls or tight corners, use pre-cut wrap or joiners to prevent air leaks.
Change the Filters
Air filters continue to collect dust even during low-use periods. Replace filters before winter so the system starts clean when used again. Clogged filters trap moisture and restrict airflow, which reduces system efficiency and allows mould to grow.
Check the manufacturer’s recommended filter type. If reusable, clean with warm water and dry fully before reinstalling. Replace disposable filters with the correct size.
Avoid Moisture Build-Up Around the System
Ensure the outdoor unit sits on a stable, level surface with adequate drainage. Pooled water around the base leads to corrosion and electrical risk.
Check for garden runoff, roof downpipes, or blocked drains that direct water near the unit. If needed, install gravel or a raised slab to support the base.
Schedule a Professional Maintenance Check
Even during the off-season, scheduling a system check can prevent damage. A technician can test components under low-load conditions, check refrigerant pressure, clean internal coils, and identify wear before it leads to breakdown.
End-of-season servicing is also a good time to address small faults found during use — such as weak airflow, short cycling, or temperature inconsistencies. Fixing these early avoids longer delays when service demand increases during peak months.
Improve Home Insulation to Reduce System Strain
Reducing indoor heat loss in winter helps the system work more efficiently during both heating and cooling. Sealing gaps in window frames, doors, and vents limits the temperature drop in your home.
Well-insulated homes maintain stable temperatures. This reduces the need for heating during cold snaps and prevents short cycling when the system is used occasionally for heating.
Use a Programmable Thermostat (If Heating is Enabled)
If your system includes a reverse-cycle mode and will be used during winter, install or check a programmable thermostat. Set lower temperatures when away from home, and higher settings during return hours.
Maintaining consistent, moderate temperatures reduces power draw and avoids sudden compressor load spikes.
Hogan Hot Water & Air Conditioning Advice
Winterising your air conditioning system is the best way to protect it when not in use. Simple steps like cleaning, checking parts, and insulating pipes prevent damage that’s often missed until it’s too late.
At Hogan Hot Water & Air Conditioning, we check refrigerant levels, inspect coils, clean filters, and ensure electrical systems are stable before your unit is stored for the off-season. Whether it’s a split system, multi-split, or ducted setup, we’ll make sure it’s ready for long-term performance.Don’t let neglect shorten your system’s life. Book a winter check now and avoid damage while the system rests. Contact us to schedule your off-season service today.