Air Con Dusty??

[phippsey]

Recently my air con smells dusty.

Ideas on how to fix if anyone has had this problem.

I had a similar episode on a defender and it sorted itself after a while, but this time it hasn't.

[DanielS]

Hey Phippsay,

Mine smelt dusty to so I removed the whole unit.. I didnt need it anymore. But in removing it I found that the evaperator (spelling??) was full of dust and rubbish, Im not 100% sure how you could remove it without disconnecting it though.

Daniels

[David_S]

Try cleaning the fins of the evaporator unit. They clog up on the air intake side. Usually difficult to get at but an old toothbrush and short bits of wire are handy. Last time I did this I just removed the carpets and used a waterblaster on low power. Worked fine without too much mess, but it is not recommended procedurre on a flash truck! Removing the evaporator unit requires degassing the system which is a right bore and expensive to regas.

David

[phippsey]

ok I'm not keen on removing the unit or pressure cleaning the cab
just yet!

So how do I access these fins with the ole toothbrush??

[David_S]

You find the evaporator unit in the cab usually located under the dash. It is connected directly to the fan unit. In AC mode the fan draws warm air from the cab through the fins of the evaporator unit where it is cooled and then blown by the fan to the outlet. The evaporator unit looks like a small radiator. It is where the refrigerant liquid evaporates and cools the air. So if you can find a small radiator connected to the heater and fan unit this will be the evaporator. There will be two refigerant pipes attached to the evaporator unit. The incoming one will be from the receiver/dryer which is usually mounted close to the condenser (another radiator mounted in front of the real radiator) and the outgoing one (wrapped in black sticky tape in the picture below) will connect with the compressor.

At least that is the system on my old MQ but I can't see that it will have changed much over the years. However whereas my evaporator unit is pretty easy to spot later models will no doubt have concealed it for aesthetic reasons. You might have to remove some cowling for example to get at it.

To show you what I am talking about have a look at the attached pictures. They show the evaporator unit on my Patrol in front of the right seat. If you are wondering where the steering wheel it is on the left on my truck (being left hand drive - it's a long story why I have an LHD Patrol in NZ) You can see the fins which have to be cleaned.

I hope this is not too confusing,

David

[David_S]

The other thing to check is that the pipe which collects any condensate water from the evaporator is not blocked. You can see this pipe at the bottom of the unit in the first picture. It leads through the firewall and discharges to the ground.

David