Evaporative Cooling During Bushfire Smoke and Dust in Albury-Wodonga

Every few summers the border gets a run of days when the sky over Albury and Wodonga turns brown. Sometimes it is smoke from fires in the high country or further afield, sometimes it is a dust front rolling in ahead of a change. Either way the same question lands in our inbox: should I keep the evaporative cooler running, and is it pulling all of that into the house?

The honest answer is that it depends on which system you have, how bad the air is, and what you are prepared to put up with. This guide explains what actually happens inside a ducted evaporative system on a smoky day, how a refrigerated ducted system behaves differently, and what to check once the air clears.

How an evaporative cooler handles outside air

A ducted evaporative system works by drawing large volumes of outside air through wet pads, cooling it as the water evaporates, and pushing it through the house and out through open windows. It is a once-through system. There is no recirculation, which is exactly why it performs so well in dry inland heat and costs so little to run.

The flip side is that whatever is in the outside air is coming in. The wet pads do capture a share of coarse dust and some larger particles, but they are not a filter in any engineered sense. Fine smoke particles pass through readily. On a heavy smoke day, running an evaporative cooler flat out will generally bring the smell and the haze indoors.

Should you switch it off?

On a day when smoke is visible but the heat is serious, most households have to weigh air quality against temperature.

Running the cooler on fan-only does not help. Fan-only still moves outside air through the house at full volume; it simply skips the cooling. If the goal is to keep smoke out, the unit needs to be off and the windows shut, and the house relies on its thermal mass until the air improves.

If you must run it, a lower fan speed with fewer windows open reduces the air change rate and therefore the amount of smoke arriving each hour, while still giving some cooling.

Dust fronts are usually short. Smoke events can last for days. For a single dusty afternoon, switching off and waiting is simple. For a prolonged smoke episode in a hot week, the limitations of a once-through system become very real, and this is one of the few situations where the case for refrigerated cooling in Albury-Wodonga is clear-cut rather than a matter of preference.

How refrigerated ducted air conditioning behaves

A refrigerated ducted system recirculates the air already inside the house. The return air grille draws room air back through a filter, across the indoor coil, and out through the outlets again. Apart from normal leakage around doors and windows, it does not pull outside air in to work. On a smoke day you close the house up and the system keeps cooling it, and the return air filter does some work on whatever particles are already inside.

That does not make the house sealed. Standard return air filters protect the coil rather than clean the air to a medical standard, and smoke will still find its way in over a long event. But the difference in indoor air on a bad day is substantial, and homeowners who have lived through a long smoke season with evaporative cooling often raise this as a reason for looking at an evaporative to refrigerated changeover, or at add-on refrigerated cooling where gas ducted heating is already in place.

Our view is unchanged: evaporative remains an excellent choice for most of the border's summer, and smoke days alone rarely justify replacing a sound system. But if you are already weighing up a changeover for other reasons, the way each system handles smoke and dust is a legitimate factor to put on the list.

What smoke and dust do to the cooler itself

A dust front loads the pads with fine grit, which settles into the pad media and the water in the tank. The pump then circulates that dirty water, and over a season it clogs the distribution channels along the top of each pad, so parts of the pad run dry and cooling falls away. Smoke leaves a fine residue that holds dust and encourages the pad to clog sooner.

After a notable dust or smoke event it is worth doing a basic check. Look at the water in the tank through the drain or bleed point. If it is clearly discoloured, drain and refill. Check the pads from outside where you can safely do so: if they are visibly loaded, a gentle rinse with a hose on low pressure helps, but avoid high-pressure washing because it damages the media.

If cooling performance drops noticeably after a dusty stretch, or the unit starts smelling musty when it runs, the pads may need replacing earlier than the usual cycle. Pad condition, pump health and water distribution are the core of our evaporative cooling service and repairs work across Albury, Lavington and Wodonga, and a dusty season is a good reason to bring the service forward rather than wait.

Refrigerated systems need attention too

Dust is not kind to refrigerated systems either. The outdoor condenser sits in the weather and its coil collects grit and grass seed, which reduces its ability to reject heat and pushes running costs up. After a dust storm, a visual check of the outdoor coil and a gentle rinse with a hose if it is plainly coated is worthwhile. Indoors, the return air filter loads up faster during smoke and should be cleaned or replaced sooner than usual, since a blocked filter restricts airflow and is a common reason a ducted system loses capacity on hot days.

Preparing before the season

If smoke-prone summers are a concern, the useful preparation is modest. Know where your cooler's isolation switch is, so it can be shut down quickly. Book servicing early so that pads are fresh going into summer. And if you are planning a new installation in Thurgoona, Baranduda or anywhere else on the border, talk through how you want the house to behave on a smoky day as part of the decision between evaporative and refrigerated, rather than discovering the trade-off in February.

Whichever system you run, we service both and will give you a straight answer about what yours needs after a rough stretch of air.