AIR CONDITIONING • SERVICES & GUIDESBucurești & Ilfov · 0764 012 943
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Is a spray enough to sanitise an air conditioner?

Editorial guide · Revised 8 October 2026

In short Short answer: no, you paid for an air freshener applied onto biofilm – exactly what the EPA describes as a practice with no demonstrated effectiveness. Real sanitising starts with physically removing the layer (pressure washing, with a cover, black water in the bucket) and only then applies the solution; if no water came out of the unit, nothing was sanitised.

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.

Situation discussed

Aviației, flat, 12,000 BTU Samsung, 4 years old. I called a company from the internet for sanitising. The mouldy smell was back after three days. Is that sanitising? See current rates on the Prices page.

Editorial explanation · Revizie AC

What is really happening

Spray on a dirty evaporator cannot penetrate: biofilm is a protective polysaccharide matrix in which bacteria and fungi sit shielded from disinfectant; the surface gets perfumed, the layer stays. The reference study on split units cut contamination by over 99% through detergent, brushing and pressure rinsing – not spraying. One more detail: 'killed' mould stays allergenic; even a biocide that worked would leave the allergen in place unless washed off. So 'it came back after three days' is not a return – it never left.

Explanatory diagramFour services, different purposes
Four services, different purposes
  1. Inspection: assessing condition and symptoms.
  2. Service check: checks and measurements appropriate to the unit.
  3. Cleaning: removing deposits.
  4. Sanitising: suitable treatment of cleaned surfaces.

The actual scope is confirmed before the visit.

What the studies say
  • EPA warns that the effectiveness of biocides sprayed into air systems has not been demonstrated and their health effects are uncertain. [US EPA, 2024]
  • EPA principle: mould must be physically removed, not merely 'killed'; biocides are not recommended as routine practice. [US EPA, 2024]
  • Mould remains allergenic even when dead, so merely 'killing' it with a spray does not solve the problem – it must be physically removed. [US EPA, 2024]
  • Washing with alkaline detergent, brushing and high-pressure rinsing reduces fungi inside the unit by more than 99%. [Indoor Air, 2023]

What we do on site

  1. We show you the roller and the back of the evaporator with a torch – you will see the layer is intact under the perfume.
  2. Sealed double cover, 2 m hose to the white bucket, foil.
  3. Alkaline detergent, contact time, adjustable pressure wash in place; roller blade by blade; pan and hose until clear.
  4. Only now the sanitising solution, on clean surfaces; filters washed; outdoor unit washed in place.
  5. Start-up test together and the bucket of clear water at the end. See current rates on the Prices page.

What you can do yourself

  • See current rates on the Prices page.
  • In future, ask on the phone: 'is it washed with pressure water and is a cover used?'

What NOT to do

  • See current rates on the Prices page.
  • Do not accept a 'leave-on, no-rinse solution' on a dirty unit.

Prevention

One real sanitising a year; with spray, however many, it stays dirty.

When to call us

0764 012 943, WhatsApp, Monday–Saturday 08:00–20:00; Aviației is close.

Spraying the cleaning solution on the indoor coil inside the cover, wearing a mask
Spraying the cleaning solution on the indoor coil inside the cover, wearing a mask
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Sources (6)

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.