If the AC has been unused for a while, test it ahead of the hot weather. You have more time to investigate poor cooling or a drainage problem when you aren't already relying on it. Alongside that test, follow the unit's maintenance instructions and be clear about which checks need a professional.
Do the user jobs in the manual
Clean or replace accessible filters as instructed and keep airflow clear. Watch for new smells, noise, water marks or a room that takes much longer to cool. Follow isolation instructions for cleaning; don't spray internal electrics.
Look at the outdoor area for obstructions or visible deterioration, but leave guards and technical parts alone. A pressure washer can cause damage you were trying to prevent.
Ask what a service includes
If you're paying for a professional visit, get the scope: cleaning, drainage, operating checks, electrical observations and outdoor condition as appropriate to the system. A filter rinse alone is something very different from a technical service.
Use a properly enabled maintenance company for regulated work. Follow the manufacturer and applicable maintenance requirements when setting the schedule; the right interval depends on the system and use.
Plan checks for a holiday property
Ask the keyholder to look for leaks or error displays between visits and arrange an operation check ahead of your arrival. If you use the unit for winter heating too, test that mode before the colder season. Keep maintenance reports with the model details so a repair technician can see the history.
Use the system sensibly between services
Shading the room helps reduce cooling demand. Avoid an unnecessarily low temperature setting: setting 16 degrees doesn't make the home reach your desired temperature faster. Clean filters as instructed and report a change in noise, drainage or performance instead of waiting for the next scheduled service.
Before you go ahead
- Manual and model recorded
- Filters checked
- Drainage observed
- Pre-season test completed
- Professional service scope documented
Common questions
How often should it be serviced?
Follow the manufacturer and any applicable installation-maintenance requirements. Usage, environment, system type and condition determine the sensible interval.
Can I pressure-wash the outdoor unit?
Do not improvise cleaning that can damage fins or electrics. Follow manufacturer instructions or use a qualified technician.
Sources and further reading
Official information checked on 12 October 2026. Rules and procedures can change; verify the live source for your exact circumstances.