How to avoid and remove bad smells in the air conditioner

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How can we avoid and remove bad smells in our air conditioner?

Some time ago we explained the most frequent causes  that can produce bad smells in our air conditioning equipments. Today, we go one step forward and we are going to see the way to avoid them, and in case we already have them, how to remove these smells once and for all.

If you don’t know why you can have this bad smells in your air conditioner, we recommend to read the article where we explain the most common reasons why these smells are produced.

Why does an air conditioner smell bad?

How to avoid bad smells in the air conditioner

If we remember what we mentioned in the article where we explained the reasons of this bad smell and making a brief summary, we can see that bad smells are caused by these three reasons:

1. Dirtiness in the internal unit -exchanger, drainage tray, fan or filters-.
2. Drainage, the smells isn’t produced by the machine itself but because of the drainage.
3. Movimiento de aire, la máquina no huele, solo mueve un aire viciado con mal olor “incorporado”.

Once we have these three points clear, we are going to see these three points one by one.

Dirty internal unit

A dirty internal unit, that is, filters, fan, exchanger or the condensate tray itself, produces a bad smell due to the amount of dirtiness and moisture which end up creating a sort of mud where fungi appear which are responsible of these smells. So in order to avoid that we have to keep our conditioning unit clean and dry as much as we can.

We already explained the proper way to clean filters of an air conditioner so you better check this article if you have any doubt about it:

How to clean air conditioner filters

In order to clean the exchanger of the internal unit, fan and drainage tray you can see this other article:

Cleaning an air conditioner

Once we know the biggest problem we face is to keep our air conditioner clean and seeing how can we do it, let’s talk about moisture.

Moisture helps a lot in the apparition of fungi so in order to remove them we have to remove also this moisture.

But the air conditioner doesn’t remove moisture? Yes, of course it does! The air conditioner removes moisture because this condensates in the internal exchanger, but the problem appears when the water gets stuck in the machine itself and in the drainage tray.

So how can we remove this water?

In order to remove this water we must ‘dry’ the machine. Some modern machines already have self-cleaning functions, others even have plasma filters which remove the 99% of virus and bacteria. But not everyone can afford one of these, so in order to remove fungi from our machines we must do this:

When summer is over and we stop using our air conditioner, we have two options:

1. Put the unit in ventilation mode for a couple of hours in order to dry the machine. This will remove most part of the water stuck and will prevent fungi to appear in our air conditioner.
2. If we are in a hurry or fungi have already appeared, put the equipment in heat or heat pump mode.

We advise to do this every time the cold season ends, either the machine smells or not, because this will prevent these smells to appear the following year.

The air conditioner has smells from the drainage

If the air conditioner has smells from the drainage, these are the two causes which appear together why this happens:

1. The drainage of the internal unit is connected to the main drainage of the house.
2. This drainage which goes from the internal unit to the main one doesn’t have a trap or it is very small.

This video belongs to the image above.

What to do in these cases:

• Make a trap in the drainage or if it already exists, make it bigger so it can have more water and it can’t dry and therefore not having bad smells.
• Place a water pump in the drainage of the internal unit. Water pumps have check valves so they won’t let anything to pass to the internal unit.
• Place a stopcock in the drainage of the internal unit. This is risky because we don’t have to forget to close it in winter.
• Change the drainage place to a place where it can’t catch smells, like a bottle, bucket, shower, etc.

Foul air flow

This is a complicated one and it only appears in piping units which don’t have return pipes because they can absorb plenty of smells from the ceiling, kitchen, our neighbours, etc.

As mentioned, only by removing the seat of the bad smell we can solve this problem which, in any case, it isn’t a problem of the equipment itself but something external.