The unit runs non-stop and never reaches 24 °C – it uses a fortune. Dirty or undersized?
This page explains a situation in an editorial format. It is not an open discussion board or a verified customer review. Contact us on WhatsApp about your own appliance.
Colentina, 28 sqm living room with a south-facing window, 12,000 BTU Gree, 6 years old. At 35 °C outside, set to 24, it runs continuously and the room stays at 27. Last year it seemed to make it. The meter is spinning. Is it dirty, or too small for the room and needs replacing?
What is really happening
This description suggests a possible cause that needs checking at the unit. Age, price or symptoms alone cannot confirm the fault, contamination or work required.
- Average electrical input, in kW.
- Operating time, in hours.
- Estimated energy, in kWh; actual use varies.
BTU describes thermal capacity, not electrical consumption directly.
- Fouling of the outdoor condenser raises pressure drop and condensing pressure, reducing the split unit's capacity and efficiency. [Science and Technology for the Built Env, 2019]
- A typical evaporator fouls enough to double its pressure drop in about 7.5 years, reducing airflow by 5–7% and raising fan power by 1–10%. [Lawrence Berkeley National Laboratory / , 2002]
- Replacing a dirty, clogged filter with a clean one can lower an air conditioner's energy consumption by 5–15% (US DOE). [US Department of Energy – Energy Saver, 2024]
- The evaporator and condenser coils accumulate dirt over time and should be checked every year and cleaned as necessary (US DOE). [US Department of Energy – Energy Saver, 2024]
What we do on site
- We measure the delta T on arrival and photograph the evaporator, roller and condenser.
- Indoor: sealed double cover, alkaline detergent, adjustable pressure wash of the evaporator (front and back), roller, pan and hose; sanitising; filters.
- Outdoor on the balcony: washed in place, from inside out – 6 years on a boulevard yields a thick grey layer.
- Interpret the temperature difference together with airflow, humidity, operating mode and the model documentation. One value cannot establish dirt, low refrigerant or incorrect sizing.
- See current rates on the Prices page.
What you can do yourself
- Blinds/curtains drawn on the south window between 12 and 18 – cuts the load more than any cleaning.
- Set 25–26 °C in a heatwave, fan on 'High', not 'Auto'.
- Filters every two weeks.
What NOT to do
- Do not replace the unit before seeing it clean.
- Do not accept 'low refrigerant' without pressure measurements and a clean unit.
Prevention
Unit at the edge of its sizing: annual clean before the season is a must – it has no margin for dirt.
When to call us
0764 012 943, WhatsApp, Monday–Saturday 08:00–20:00; Colentina is 20 minutes away.
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Sources (4)
The information on this page is educational and based on cited sources; it does not replace medical advice. We do not do repairs, installation or refrigerant circuit work.