Aircon Service Checklist: When to Call a Pro vs DIY
The honest split: filter cleaning and a basic visual inspection are fine to DIY every 1-3 months in heavy-use season. Anything involving refrigerant, electrical work, chemical coil cleaning, or the inside of the outdoor compressor needs an ARC-licensed technician — both because it’s the only way to do the work safely and legally, and because manufacturer warranties typically require professional servicing to remain valid. For most Adelaide installs, a $200 annual service performed by a qualified pro plus 1-3 monthly filter cleans by you is the right balance.
This guide walks through what each side actually involves, what kit you need for the DIY parts, what the pro does that you can’t, and when to skip the maintenance and call a repair specialist instead.
The five-second answer
| Task | DIY? | Frequency |
|---|---|---|
| Filter clean | Yes | Every 1-3 months in season |
| Outdoor unit leaf/debris clear | Yes | Every 3 months |
| Visual inspection (drips, sounds, smells) | Yes | Ongoing |
| Indoor coil chemical clean | No — pro | Annual |
| Refrigerant check | No — pro, ARC | Annual |
| Drain line clear | Pro recommended | Annual |
| Electrical inspection | No — pro | Annual |
| Performance test against spec | No — pro | Annual |
What you can DIY safely
Filter cleaning (every 1-3 months in heavy-use season)
The single most important DIY maintenance task. A blocked filter is the #1 cause of poor cooling performance, accelerated coil contamination, and (eventually) premature compressor failure. The good news: cleaning is genuinely easy and you only need 5 minutes per indoor head.
How to do it:
- Switch the unit OFF at the wall (not just at the remote — kill the actual power)
- Open the front panel of the indoor head (usually two clips at the top, hinges at the bottom)
- Remove the filter (slides out, no tools required)
- Wash with warm soapy water — gentle scrubbing with a soft brush is fine
- Rinse thoroughly under running water
- Pat dry with a tea towel; let air-dry for 30 minutes
- Refit and close the unit
Replace filters that are damaged or won’t clean to white — typically every 12-18 months for budget filters, longer for premium types.
Frequency in Adelaide:
- Heavy-use season (Nov-Feb, Jun-Aug): every 4-6 weeks
- Shoulder season (Mar-May, Sep-Oct): every 8-10 weeks
- Off-season: every 12 weeks
- Coastal suburbs (Glenelg, Henley Beach): double the frequency — salt and marine particulate load filters faster
Outdoor unit leaf and debris clearing (every 3 months)
The outdoor compressor needs unobstructed airflow to work efficiently. Eucalyptus leaf litter, gum bark, dust and the occasional small twig or bird debris accumulate against the fins and inside the unit casing.
How to do it:
- Switch the system OFF at the wall
- Wait 5 minutes for the fan to stop fully
- Clear all leaves, bark and visible debris from around the unit (within 1m)
- Use a soft brush or hand to clear any debris stuck in the bottom intake grille
- Look at the fin face — if there’s visible dust or fine debris, a gentle hose-down (low-pressure spray, not pressure-washer) is fine. Avoid soaking the electrical compartment.
- Don’t open the unit. The cover comes off only for licensed technicians.
- Clear a 1m radius around the unit of any plants, mulch or stored items
For substantial overhanging-branch issues affecting the unit, you’re looking at tree work — Tree Fox tree services covers tree pruning across the Adelaide eastern suburbs and the Hills.
Visual inspection (ongoing)
Things to keep an eye on:
- Water dripping from the indoor unit — almost always a blocked condensate drain. Switch the unit off to prevent ceiling/wall damage and call.
- Loud bangs, rattles, grinding — failing fan motor bearings or loose mounting bracket. Don’t run the unit; call.
- Smell of burning, electrical, or hot plastic — switch off at the breaker immediately. Don’t restart. Call urgently.
- Cooling has weakened slowly over weeks — likely refrigerant leak. Book a service.
- Outdoor unit is iced over (visible white ice) — refrigerant low or fault. Switch off and call.
- Unit short-cycles (turns on and off rapidly) — likely controller fault, capacitor wearing, or thermostat issue. Book a service.
What needs a pro
Indoor coil chemical clean (annual)
Indoor evaporator coils accumulate dust, cooking film, biofilm and (in coastal installs) salt residue. Filters catch most of the gross particulate but the fine layer that gets through builds on the coil over time, reducing heat-transfer efficiency by 10-25% and providing a substrate for mould growth.
A chemical clean involves:
- Removing the indoor unit casing (specialised access)
- Spraying coil-cleaning chemical (alkaline foam, manufacturer-approved)
- Allowing dwell time
- Rinsing with controlled water flow
- Catching and disposing of the wash-off
DIY this with a hardware-store coil cleaner and you’ll either damage the coil, void the warranty, or end up with a wash-off that floods your ceiling. Professional pricing is $80-$160 on top of standard service — it’s worth it.
Refrigerant pressure check and top-up (annual)
The refrigerant circuit is sealed under pressure. Any work on it requires an ARC Authorisation — the licence verifiable at arctick.org. Refrigerant work without an ARC licence is illegal under federal Ozone Protection law, and the work involves:
- Connecting manifold gauges to the service ports
- Reading suction and discharge pressures against manufacturer specs
- Identifying leaks (usually with electronic detector or UV dye)
- Recovering refrigerant where required (mandatory under Refrigerant Reclaim Australia rules)
- Adding refrigerant to spec
DIY refrigerant work is illegal, dangerous (refrigerants under pressure cause serious injury and skin burns), and immediately voids any manufacturer warranty. This is the hardest line in the DIY/pro split.
Drain line clear (annual)
Indoor unit condensate drains accumulate algal growth and debris. A blocked drain causes water to back up into the indoor unit and drip onto the wall or ceiling.
A pro clears the drain by:
- Using compressed air or a wet/dry vacuum to clear the line
- Flushing with manufacturer-approved cleaner
- Confirming flow at the outlet
DIY: you can usually flush a partially-blocked drain with a cup of warm water at the indoor unit’s drain outlet — but if water backs up rather than flowing, you need professional clearance.
Electrical inspection (annual)
The electrical side of an aircon involves the supply circuit, the outdoor compressor wiring, the capacitor, contactor, fan motor connections, and the indoor unit power circuit. A pro inspects:
- Visual condition of all connections
- Capacitor reading (microfarad spec against nameplate)
- Contactor wear
- Insulation resistance check
- Earth continuity
DIY electrical work on aircon requires a state electrical licence. Without it, you’re not insured and you’re voiding the unit warranty.
Performance test against spec (annual)
The pro measures temperature differential at the indoor head against manufacturer-rated performance, confirms the system delivers nameplate kW, and identifies any underperformance before it becomes a fault. This is the diagnostic step that catches slowly-developing problems.
Annual service — what’s actually in it
A standard 60-90 minute split-system annual service covers:
- Filter clean or replacement
- Indoor coil clean (chemical if needed)
- Outdoor coil clean
- Drain line clear
- Refrigerant pressure check
- Electrical check
- Performance test
- Brief written report
Indicative pricing:
| Service | Cost |
|---|---|
| Single split-system service | $180-$280 |
| Multi-head split (3 heads) | $280-$420 |
| Ducted reverse-cycle service (4 zones) | $280-$450 |
| Ducted gas heater service | $220-$340 |
| Evaporative cooler service (incl. pads) | $280-$420 |
For full pricing and scope, see the aircon service page.
Service frequency rules
| System | Inland Adelaide | Coastal (Glenelg, Henley) |
|---|---|---|
| Standard split | Annual | Every 6 months |
| Multi-head split | Annual | Every 6 months |
| Ducted reverse-cycle | Annual | Every 6 months |
| Ducted gas heating | Annual (before winter) | Annual |
| Evaporative cooler | Annual (before summer) | Annual |
| Commercial / heavy-use | Every 6 months | Every 4 months |
The coastal 6-month rule is real — salt-aerosol loading on outdoor coils accelerates corrosion if left for 12 months. Salt washing every 6 months extends unit life from 8-10 years to the full 15-20 expected.
When to skip service and call repair
If you’ve already got an active fault, skip the service and book a repair callout instead:
- No cooling or weak cooling — diagnostic visit, then repair
- No power / not turning on — diagnostic visit, then repair
- Loud bangs, grinding or burning smells — emergency callout, don’t run the unit
- Dripping water inside — switch off, call repair
- Outdoor unit iced over — switch off, call repair
A standard service won’t fix a fault — it’s preventative. A diagnostic visit ($120-$220) is the right starting point for any active problem.
Frequently asked questions
Can I DIY the filter clean? Yes — it’s the standard homeowner maintenance task. Switch off, remove filter, wash, dry, refit. 5 minutes per indoor head every 4-6 weeks in season.
Why can’t I just spray garden coil cleaner on the indoor unit myself? Three reasons: most hardware-store coil cleaners aren’t manufacturer-approved (will void warranty), the rinse-off floods ceilings if uncontrolled, and removing the unit casing without proper access procedures can damage components. Pros use the right chemicals and the right access.
How do I know if my unit needs more than a standard service? Three flags: cooling has weakened over weeks, water dripping inside, or unit is making new sounds. Any of these and you need a repair diagnostic rather than a standard service.
Will service void my warranty if a third party does it? No — provided the service tech holds the right licences (ARC, electrical) and uses approved chemicals. Most manufacturer warranties simply require “regular professional servicing” — the specific tech is up to you. We hold all the required licences.
How often should I service in coastal Glenelg or Henley Beach? Every 6 months. Salt-aerosol loading accelerates corrosion if the outdoor coil isn’t cleaned twice per year. The Glenelg location page and Henley Beach location page cover the coastal service interval.
What if I haven’t serviced my unit in 5 years? Book a service. Costs $200-$400 (standard service plus likely chemical coil clean), often catches developing problems, and gets the unit back to spec. The alternative — keep running unserviced — typically results in a $1,500+ repair within 2-3 years.
Do you offer annual service plans? Yes — we offer 12-month or 24-month service plans with 15-20% off rack rates for multiple units (multiple properties, commercial premises). Flag in the form notes when you submit.
Ready to book a service or get a service quote?
Submit the quote form or call us — we’ll be in touch within 24–48 hours.