Craftsman replacing a ventilation system hose

How do I clean a VMC duct?

In theory, the cleaning of a ventilation duct should be carried out every 5 years. The duct is difficult to access and fragile in design, yet it is rarely maintained. Whether you have a Controlled Mechanical Ventilation If you want to carry out the maintenance yourself, it is best to follow a few precautions.

What are the risks associated with a blocked or damaged ventilation duct?

A real lung of your house, the VMC duct is the main element of your ventilation system allowing the air to circulate in your home. In the presence of a blocked duct, stale air and moisture cannot be expelled to the outside, while a damaged duct will only release dust particles and polluted air into your home. A defective duct means risks to your health Asthma, rhinitis and chronic coughing are the main respiratory diseases that you are exposed to if you have a poorly maintained ductwork.

In addition to the risks to your health, a blocked duct can lead to over-consumption of electricity. As the air flow becomes more difficult to evacuate, the motor of your CMV may overheat and consume more energy. Finally, in rare cases, this overheating can lead to a short circuit and a fire, as a result of the fatty material in the motor catching fire.

How do I maintain a single flow CMV?

Single-flow CMV is the most common ventilation system in a house. Before carrying out any maintenance, you must first switch off the power supply to your CMV. If the CMV ductwork has been correctly installed, your ductwork should have a technical path and casing that allows access to the duct clamps, so that they can be easily removed and reinstalled. In this case :

  • Wear a mask to avoid inhaling the dust,
  • Starting from the motor block of your VMC, unscrew the clamps of the ducts,
  • Then pull them out and clean the ducts with a ventilation brush while sucking up the dust clumps with the hose of your hoover,
  • Then reassemble the ducts to your VMC. | Maintenance of single flow air conditioning.

If the ducts have been installed under the insulation or without an easy access point, it will be impossible to clean them. In this case, we advise you to consider installing an access path and access boxes before proceeding with the complete replacement of your ducts.

Attention : In addition to cleaning your ventilation ducts every 5 years, it is advisable to :

  • Clean the air inlets and outlets about every 3 months. Do not use any detergents for this: soapy water or white vinegar is sufficient to remove greasy stains.
  • Dust the blades inside the unit with a cloth once a year.

Be aware that even with maximum care, it is very difficult not to tear a flexible PVC duct when cleaning it. Most of the time they have to be replaced. That is why we suggest that you call in a professional.

How to maintain a double-flux ventilation system?

Double-flow ventilation uses two separate networks of ventilation ducts: the first one brings the air into your home, while the second one exhausts it. This ventilation system requires more regular maintenance to operate efficiently.

The cleaning is very similar to that of a single flow CMV, except for a few details. In addition to the elements seen above, you must :

  • Clean or replace the filters at the air inlets every 3 to 6 months,
  • Drain the condensed water in the heat exchanger siphon approximately every 6 months (in addition to dust removal),
  • Check twice a year that the air inlets are not blocked (by leaves or other).