How to Clean Your Air Conditioning Unit

Coil Clean Services
Call: 0447 112 952

How to Clean Your Air conditioning Unit


How to Clean Your Air Conditioning Unit.  License HVAC&R tradesman Daniel shares detailed instructions on how to clean your air conditioner. The accompanying youtube video shows highlights of cleaning a ducted residential fan coil unit.


Steps used in cleaning an air conditioning unit:

  • Electrically isolate and lock out the air conditioning power. Always test and prove isolation

  • To allow for easier access to FCU's [Fan Coil Units] in the ceiling void, remove the return air filter grill and box and reposition with the attached duct in the ceiling void.

  • Disassemble the FCU:

  • Remove the return and supply air plenums from the FCU.

  • Remove the FCU top panel.

  • Disconnect and remove the blower fan.

  • Cover or remove all electricals and protect against spray and water spills to the ceiling space.

  • Vacuum the coils 'upstream' face and FCU internal pannels. 

  • Wipe down and treat mould on FCU panel faces. 

  • Flush condensate drains and pan clean and ensure drainage.

  • Apply the cleaning solution to the FCU coil and alow standing time for the cleaning solution to act. Work from the bottom up and apply from the coils 'downstream' face. 

  • Use a cold water pressure cleaner, clean the coil working from the downstream face. Start at the top of the coil and slowly traverse back and forth across the face working your way to the bottom. Backwash contaminates out through the coil fins and to the condensate pan.

  • Flush and remove contaminate from the drain pan. Wipe down any overspill from pressure cleaning.

  • Dry clean or pressure clean the blower fan. Clean or replace filters.

  • Inspect and verify the cleaning by visual and/or lab test of surface lift samples. 

  • Reassemble FCU and confirm safe operation before reinstating equipment.


How to Clean Your Air conditioning Unit: Points to consider

Cleaning air conditioning equipment hazards include pressurised and electrical systems and refrigerants with a global warming potential. Protect yourself and the environment. Trade qualified and licenced contractor is required to complete electrical and air conditioning work. 


Use a HEPA rated filter on the vacuum to eliminate the spread of mould spores, insulation fibres, and dust particles.
Ensure all chemicals and cleaning agents are non-reactive with the coil and FCU's materials and not harmful to building occupants. Use food-grade cleaning solutions.
Use pressure cleaner adjustment and control spray to eliminate bending of the coil fins. Effective cleaning of the coil without damage to the fins is a skill that takes time and patience to develop. Eliminate overspray and wipe down, treat, and dry any spillover.
Inspect the coil by shining a light through the coil fins. Some cleaning technics result in a clean coil face but with clogging of the internal fin space with contaminants or bent fins. A clean coil is one that has clean faces and thoroughly cleaned fins and tube within the depth of the coil.
Wear full PPE suitable for working with mould and mist type spray.