How Often Should You Service Your Air Conditioner?

Once a year is the industry recommendation and it's genuinely correct. Skip a year and your energy bill goes up 5–15%; skip five years and you're 20–30% less efficient and much more likely to have a breakdown.

The exception is if you use the system very lightly — a spare-room split that runs 50 hours a year can stretch to every second year without harm. Anything running more than 300 hours a year needs annual attention.

Autumn (April–May) — before winter heating starts. Or early spring (September) — before summer cooling. Book early: our diaries fill up 3–4 weeks out at those times.

The worst times to book are the first cold snap in June and the first heatwave in December. That's when everyone remembers their AC exists, we're triaging emergency repairs, and routine services get pushed out.

Twice a year for typical office/retail; quarterly for kitchens, medical, and heavy-use environments.

Kitchen exhaust and make-up air needs quarterly minimum by AS 1668 — non-negotiable for compliance and insurance.

Medical settings with clinical filtration usually run on a documented preventative maintenance program with monthly checks and quarterly deep services. We provide the paperwork for accreditation audits.

Check and clean indoor filter. Wash indoor coil. Clean drain pan and flush drain line. Check refrigerant pressures against manufacturer spec. Check electrical connections and current draw on compressor and fans. Inspect outdoor coil and wash if fouled. Test heating and cooling cycles. Report on any deterioration and expected life of key components.

A service that skips the drain line and the coil wash isn't a service — it's a visual inspection. Ask what's included and get it in writing.

Most manufacturer warranties (Daikin, Mitsubishi Electric, Fujitsu) require documented annual servicing to remain valid. That doesn't mean you have to use the manufacturer's own service network, but you do need dated invoices from an ARCtick-licensed installer.

Homes that skip services often discover this the hard way at year 5 or 6 when a claim gets rejected. Keep every service invoice in a folder with your original install paperwork.

Single split, standard service: $180–$240 in Canberra.

Multi-split (per outdoor + heads): $240–$380.

Ducted (single indoor fan coil, zoned): $260–$400.

Deep clean with blower-wheel removal (as opposed to standard service): add $150–$220 per indoor head.

Wash the filter every 6–8 weeks. Keep the outdoor unit clear on all four sides. Run fan-only for 10 minutes after heavy cooling. Take photos of the outdoor unit once a year so you notice progressive fouling or damage. Log any strange noises the day they start — 'started clunking last October' is much more useful information to a technician than 'I think it's been noisy for a while'.

Refrigerant pressures at commissioning conditions.

Compressor current draw compared with nameplate.

Indoor and outdoor coil temperatures across the coil.

Filter and coil cleanliness rating (photograph before/after).

Drain pan and drain line status.

Any deteriorating components flagged with estimated remaining life.

Recommendations for the coming season.

Filter clean every 6–8 weeks in normal households; 4–6 weeks with pets or high dust. Slide out, rinse under running water, dry fully before refitting.

Outdoor unit clearance check monthly during peak use — leaves, spider webs and grass clippings all reduce heat rejection.

Drain line check — a garden hose flush at the outlet clears many partial blockages before they back up indoors.

Remote and controller battery replacement annually — flaky remotes make setpoints unreliable.

Filter cleaned, coil wiped, invoice raised. Nothing else touched. Charge $120–$150.

No refrigerant check. No electrical draw check. No drain flush. No coil wash. No report.

This is a visual inspection, not a service. It doesn't protect your warranty and it doesn't restore efficiency. Pay $80 more for a real service.

Very light (spare-room split, <100 hours/year): every 2 years, or annually if it's under manufacturer warranty.

Standard residential (300–800 hours/year): annually.

Heavy residential (open-plan living or ducted running 8+ hours/day): annually with a mid-season filter check.

Light commercial (office, retail): 6-monthly.

Heavy commercial (kitchen, medical, warehouse office): quarterly.

Annual service contracts in Canberra typically cost $250–$380 for one split, with priority booking and a modest parts discount.

Pay-as-you-go often works out slightly cheaper if you're organised enough to book in shoulder season.

Contracts are worth it for multi-unit homes, commercial premises, or anyone who forgets to book and ends up paying peak-season premiums.

Invoice under $100 for a full 'service' — that's a filter clean, not a service.

No refrigerant pressure readings on the invoice.

No electrical current draw noted.

No before/after photos of the coil or drain pan.

Ten-minute site visit. A proper split service takes 45–75 minutes.

Clear a 1-metre working zone around the indoor and outdoor units.

Put pets in another room.

Have the remote and any Wi-Fi app credentials handy.

Note down any faults, smells or unusual noises before the visit — details fade fast once the system is off.

January: mid-summer filter check. Wash if it's grey or clogged.

February: outdoor unit clearance check — grass grows fast at this time of year.

March: last hot-day cooling. Run fan-only for 20 minutes at the end to dry coils before winter.

April: book pre-winter service. Filter clean, coil wash, refrigerant check.

May: first cold nights. Test heating mode; run for 30 minutes to spot early faults.

June: mid-winter filter clean.

July: outdoor unit ice check on frost mornings. Make sure defrost is running normally.

August: filter clean, especially in homes with pets.

September: book pre-summer service if you didn't in autumn.

October: switch to cooling for first warm days. Check for water leaks from drain lines.

November: filter clean.

December: peak-season prep — outdoor unit clearance, drain line flush, remote batteries.

Manufacturer warranties on major brands require 'reasonable maintenance'. In practice, that means documented annual servicing by an ARCtick-licensed installer.

Skip years and your warranty claim on a compressor or board may be rejected. That's a $1,500–$3,500 out-of-pocket cost that a $250 annual service would have prevented.

Keep every invoice. Warranty claims in year 6 depend on year 2 paperwork.

Year 1: everything pristine. Filter check, cosmetic inspection.

Year 2–3: first signs of coil dust in bushfire regions or high-pollen suburbs. Wash restores efficiency.

Year 4–5: drain pan starts to show biofilm. First deep clean recommended.

Year 6–7: outdoor unit coating showing UV wear. Fins may need combing.

Year 8–10: efficiency loss starting to be measurable. Refrigerant top-up sometimes needed (with leak repair).

Year 10+: budget for eventual replacement; keep the unit running well in the meantime.

A recent service invoice adds credibility to a home sale. Buyers ask about AC condition; a folder with three years of service records answers the question with paperwork instead of promises.

For rental property owners, servicing between tenancies is much cheaper than fielding maintenance requests once a new tenant is in.

Offices with 20–50 staff and a ducted VRF system: quarterly service on the ductwork and filters, annual deep clean of coils and drainage. Budget $1,200–$2,400/year.

Restaurants: quarterly HVAC plus quarterly kitchen extract deep clean. Grease loading is severe; skipping quarters costs coils.

Retail tenancies inside shopping centres: monthly filter and drainage checks (often lease-mandated), quarterly full service. Landlord audits happen unannounced — keep paperwork current.

Medical clinics: monthly filter checks (part of infection-control compliance), quarterly deep service, annual air-quality audit if accredited.

Childcare: quarterly filter changes to a hospital-grade standard, quarterly deep service, plus documentation for accreditation.

Warehouses and industrial: 6-monthly minimum on refrigerated staff-area units; annual on evaporative coolers with belt and pad inspection.

Most services focus on the mechanical side. A more advanced service also tunes the controller: setpoint schedule, fan speed, defrost strategy, and app connectivity.

Good tuning can save 5–15% of running cost without hardware changes. It's part of what a premium service brings and often isn't quoted on cheap service.

Ask specifically whether the service includes controls review. If not, ask for it as an add-on — it's usually 20–30 minutes of extra time.

Written scope of work.

Fixed price, not 'from $X'.

ARCtick licence number on the invoice.

Written report at end of service with photos.

Priority booking for existing customers during peak season.

Same technician returning where possible — continuity spots faults earlier.

Local — a Canberra technician who can get to you in an hour beats a national franchise that dispatches out of Queanbeyan or Goulburn on a busy day.

'Do I really need it annually if the unit seems fine?' Yes — efficiency drift is invisible until it's severe. An annual service catches it while it's cheap to fix.

'Can I do it myself?' Filter and outdoor clearance yes; refrigerant, electrical and coil work no. ARCtick licensing applies to anything touching refrigerant.

'How long does a service take?' 45–75 minutes for a single split, 60–90 minutes for a ducted fan coil, longer for multi-splits with several heads.

'Will you find things wrong on purpose to upsell?' Reputable installers don't. Ask for photographs of any deteriorating component so you can see the evidence.

'What time of day is best?' Mid-morning is easiest — outdoor units aren't sun-baked, and technicians are fresh. Late-afternoon summer visits are hot and tiring for everyone.

Book at least 3–4 weeks ahead for autumn and spring — that's when everyone remembers their AC exists.

Bundle multiple units into one visit — the call-out is fixed regardless of unit count, so the marginal cost per extra unit is lower.

Ask for the same technician year on year — continuity of records is worth real money at year 5+.

Keep a physical or digital folder with all service invoices, install paperwork, and warranty certificates. It's the single most useful thing to have when a fault develops.