Start with the room, not the thermostat
If an air conditioner is working too hard, the room usually has a simple problem first. In Clairwood, Durban Central and other busy parts of eThekwini, we see units running flat out because doors are left open, windows leak hot air, or the room is too large for the unit size.
Begin by checking the basics before turning the temperature down lower. Close doors properly, keep curtains shut on the sunny side, and make sure people are not adding extra heat with lights, ovens or computers. A room that stays shaded and sealed needs less cooling, and that cuts the electricity bill without making the space stuffy.
- Keep doors and windows closed when the unit is on
- Close blinds during the hottest part of the day
- Switch off heat making equipment where possible
- Use fans to move cool air around the room
Use settings that save power without making the room uncomfortable
You do not need to set the unit at the lowest possible temperature to feel comfortable. In most homes and offices, a steady setting around 23 to 25 degrees works well. Every degree lower can increase running cost, especially when the weather is humid and the unit has to work harder to remove moisture.
Use the timer rather than leaving the unit on for the full day. If the room is only needed for a few hours, start the unit a little earlier and switch it off before everyone leaves. During load-shedding, allow the room to warm up slowly instead of forcing the aircon to cool a very hot space in one go, that takes more power later.
- Set one comfortable target temperature and leave it there
- Use the timer for offices, shops and bedrooms
- Do not keep changing the setting every few minutes
- Use fan speed to spread cooled air more evenly
A small note: if one room feels hotter than the rest, the cause may be poor airflow rather than the temperature setting. That is worth checking before lowering the thermostat again.
Keep filters, coils and drains clean
Dirty filters make an air conditioner pull harder for the same result. That uses more power and can also lead to weak cooling, bad smells and water dripping inside the room. In coastal areas like Durban, salt and damp air can speed up dirt build up, so cleaning should not be left too long.
For many domestic units, filters should be checked every few weeks and cleaned when they look dusty. Commercial spaces may need more frequent attention if the unit runs for long hours. Drain blockages are another common cause of wasted power because the system struggles while water backs up and airflow drops.
- Check filters every 2 to 4 weeks
- Look for dust on the indoor coil and around the return air area
- Make sure the drain pipe is flowing freely
- Book a deep clean if the unit smells damp or feels weak
If you notice ice on the pipes, warm air from the vents, or water marks on the wall, the unit may need fault finding. Leaving it to work like that usually pushes the power use up, and it can lead to a bigger repair later on.
Do not ignore small faults that waste electricity
A unit can still switch on and quietly waste power for weeks before the fault becomes obvious. A weak capacitor, a tired fan motor, a refrigerant leak or a sticking contactor can all cause the system to run longer than it should. That means higher running cost even when the room never quite feels right.
Watch for these signs: the unit starts slowly, trips often, cools one side of the room better than the other, or keeps running without reaching the set temperature. In Durban’s summer heat, these issues show up fast in offices, salons, shops and homes that use the aircon for long hours.
- Reduced airflow from the indoor unit
- Unusual buzzing or clicking sounds
- Higher bills with no change in use
- Water leaking or repeated tripping at the DB board
When faults are fixed early, the unit does not have to battle against itself. That saves electricity and helps avoid an emergency call-out during a hot spell or over a busy weekend.
Plan maintenance around how the building is used
Air conditioning should match the way the space is occupied. A small office that closes at 5 pm does not need the same schedule as a retail space with long trading hours or a home where the family is in and out all day. Planned maintenance helps keep the system set up for the real load it carries.
We usually advise checking performance before summer starts, then again if the unit is working longer hours or struggling after heavy rain and humidity. For commercial sites, a planned service can reduce breakdowns and keep the unit working at steadier efficiency. That is especially useful in South Durban and other areas where dust, heat and salt air can all affect performance.
- Book a service before the hottest months
- Review run times and room use every season
- Check remote controls, sensors and thermostat settings
- Keep outdoor units clear of leaves, rubbish and tight walls
If a unit is fitted in a cramped yard or near a wall, air flow can be poor and power use climbs. Leaving enough space around the outdoor section helps it breathe better and cool more efficiently.
Simple habits for homes and businesses in eThekwini
Saving power is often about routine. In a home, that might mean cleaning the filter on the first weekend of the month. In a business, it could mean assigning one person to check settings before opening and again at close. Small habits matter because they stop the unit from working harder than needed.
Here is a practical checklist you can use straight away:
- Set a sensible temperature and do not keep changing it
- Close doors fast in high traffic areas
- Use fans to help move cool air
- Keep filters and drains clear
- Watch for weak cooling, strange smells or water leaks
- Book fault finding when the unit is noisy or running too long
If you are comparing rooms, remember that a west facing room in Durban afternoon sun will always need more from the aircon than a shaded room. A little planning around curtains, usage times and servicing can save a fair amount over a month. That is money better kept in the business, or at home for other needs.
Aircon Depot works from Clairwood and supports Durban Central, South Durban, North Durban, West Durban and the wider eThekwini area. For advice on cutting running cost, or for a service, repair or gas check, contact depot@aircondepot.co.za.
