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Someone at work mentioned a couple of days ago that his A/C pump was causing his engine to stall (don't worry, it's only a Mondeo )
I didn't realise that when the A/C systems are set in 'Demist' mode the pump is active.

Does the Dryer section have the heat guided into the cabin as well as the heeat from the engine?

I tried setting the ACC to economy this morning, and the fact that the air is not being dryed by the A/C makes a big difference as to how much misting I get.

I looked at the pump after the drive home from work and pushed the front screen demist button, sure enough the A/C kicked in and stayed on for a while, though it does turn off every now and again, and the pipes to and from the pump both felt cold.

Just a technical query as opposed to a problem.

Skiddins
 

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The A/C simply cools the air on the way in. Cold air cannot hold as much moisture as warm air, so the excess moisture drops out as liquid on the cooling coils, and the drains away via the (blocked?) drains in the aquarium. After it has been cooled and dried, the air passes through the heater matrix and become warm, but still dry, air. I believe that unless you press the ECON button, the compressor will run whenever it needs to, governed only by the system pressure. When you press the defrost button, the fan goes to high speed, so a lot of heat is put into the A/C system (or it has a lot of air to cool, if you prefer), and the compressor has to work hard to remove it, hence you see it engaged most of the time.
 

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Skiddins, firstly you know what they say about assumption and presumption- they're the mother and father of all cock-ups


The aquarium drain exits in a single flexi pipe at the back of the engine compartment in the middle, just in front of the bulkhead. The end of it is formed into a slot, which is designed to allow the condensate out but can get clogged. The best way to check it is to get underneath I'm afraid.
 

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There is a single drain from the air box into the space below the plastic cover. This is a rubber tube with a flattened end. The end tends to get full of stuff and blocks. You can clean it out with a piece of bent wire once you have removed the cover. There are two further drains that drain from behind the bulkhead. They are J shaped rubber things that sit above the steering rack. One faces forward and the other back. They have rubber flaps overs the end, but you can get a finger in to remove leaves, twigs etc. It's easiest from below.

In my experience, it's the single flat ended drain from the heater box that is most likely to be clogged up.

It is unlikely that these would be checked during a service.
 
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