Why Dubbo summers are hard on a system
Months of serious heat
At Dubbo Regional Airport AWS, January's mean daily maximum is 33.6 degrees, and the record is 46.1. AdaptNSW says the Dubbo area averages 20 to 30 days a year above 35 degrees.
Bright, dry and sunny
Afternoon humidity at the airport averages just 32% in January, and Dubbo gets 148.6 clear days a year. Outdoor units sit in strong sun through a long season.
Frost in winter too
July's mean minimum is 3.1 degrees, with some early morning frost, so a reverse cycle system here gets a second workout in heating.
What heat does to a system that's overdue
ActronAir says an air conditioner loses cooling capacity above 35 degrees, using the example of a 14kW system dropping to 10kW or 12kW. On a 40 degree afternoon there's no spare capacity left to cover a dirty coil or a clogged filter, which is why a tired system usually shows it in a heatwave rather than in October.
Daikin says blocked filters can reduce efficiency significantly, and recommends cleaning or changing them at least once a month through summer. It also says leaves and debris around the outdoor unit make it work less efficiently. The ACT Government's guide warns against boxing in an outdoor unit, so if you're tempted to shade one from Dubbo's sun, make sure the screen doesn't block its air.
What a pre-summer service in Dubbo should cover
- Filters, coil and indoor fan cleaned on each indoor unit.
- The outdoor coil cleaned, and the space around the unit checked so it can breathe.
- The refrigerant charge checked by a full RAC01 licence holder, with any leak found and repaired rather than topped up.
- On a ducted system: the return air filter, the zones and a look at the ducts, as Daikin's tune-up list includes.
- A heating test too, before the frosts.
Evaporative coolers are a separate service
If you have an evaporative cooler, it needs servicing by someone who works on them every week. It's a different trade from refrigerated air conditioning: no refrigerant, but pads, pumps, water and a roof unit.
Seeley says its evaporative coolers should be serviced after the first year, then every two years, with more frequent servicing in harsh environments. Bleed-system models need seasonal maintenance before and after summer. Our evaporative cooler service page covers pads and parts.
What makes a Dubbo service bigger or smaller
Each indoor unit is cleaned on its own, so the count matters most, and a ducted system adds a roof space and a return air filter. An outdoor coil packed with several summers of grass clippings and dirt takes longer. A unit that's been struggling may turn the visit into a fault-find, quoted separately.
Your part, and the technician's
You can
- Clean or change the filters at least monthly through summer, or as your manual says.
- Keep the area around the outdoor unit clear, and don't screen it in.
- Turn the unit off at the power before taking filters out.
- Note any rooms that won't cool on hot days, and tell the technician.
Leave to a licensed installer
- Cleaning the indoor and outdoor coils.
- Refrigerant checks and any leak repair.
- Electrical connections and controls.
- Anything on the roof, including an evaporative cooler.
Questions to ask a Dubbo technician
- Do you hold an RAC01 licence, and what's your RTA number?
- Will you clean the outdoor coil, or only the indoor filters?
- Is anything near the outdoor unit restricting its airflow?
- Do you also service evaporative coolers, or should I book someone separately?
What we'd do
What we'd do in Dubbo
Book the refrigerated system's service in September or October, ask for the outdoor coil to be cleaned as well as the filters, and keep the filters clean monthly until autumn. If you also run an evaporative cooler, book a specialist for that before the first hot week. The national service guide has more detail, and the Dubbo page helps if you're choosing a new system. Send us the job and licence-checked local technicians who specialise in it can see it, where we have them. If none near Dubbo takes it within 48 hours, technicians elsewhere in NSW may see it too. Only the technician who takes it receives your contact details, and we never sell them on.
