On our car I recogneized , can also use the aircon on a lower level without running the motor, and the key is still inserted?

How long I can use aircon when not drive, until battery is emty?

I am not sure, but when you turn off the engine, the aircon doesn't work any more (cq doesn't blow cold air), however the fans still work, so you will get the same effect as a Padlom (or Fan).

But I could be wrong.

Not every car same!

On our car aircon works also when engine off this why I ask this question

Do you have a hybrid than, as I've never heard of a car with an electric AC compressor as that is what you would need to keep it still cooling without the motor running.

Not every car same! On our car aircon works also when engine off this why I ask this question

Which model car do you have?

If your car really does have an electric compressor then the equivalent of a 3000BTU aircon will likely get your battery to a point where it won't start the engine in about half an hour.

I have noted that our car aircon continues to pump cool air for some minutes after the (engine driven) compressor is stopped, is that what our OP is seeing?

Not every car same! On our car aircon works also when engine off this why I ask this question

Which model car do you have?

If your car really does have an electric compressor then the equivalent of a 3000BTU aircon will likely get your battery to a point where it won't start the engine in about half an hour.

I have noted that our car aircon continues to pump cool air for some minutes after the (engine driven) compressor is stopped, is that what our OP is seeing?

They need the engine for Refrigeration, after that its just the Fan blasting the condenser slats There are no Electric Air-cons in Cars, only Buses and Motorhomes driven with a separate Jenny {Honda} Engine.

Not every car same! On our car aircon works also when engine off this why I ask this question

Which model car do you have?

If your car really does have an electric compressor then the equivalent of a 3000BTU aircon will likely get your battery to a point where it won't start the engine in about half an hour.

I have noted that our car aircon continues to pump cool air for some minutes after the (engine driven) compressor is stopped, is that what our OP is seeing?

There are no Electric Air-cons in Cars, only Buses and Motorhomes driven with a separate Jenny {Honda} Engine.

That is why I mentioned hybrids as some do. Both Prius and Toyota Camry have hybrids and perhaps others in Thailand. That's why we need to know what he is driving to give a proper answer. As Crossy indicates, it will continue blowing cool air for some time after the engine is off due to residual cooling in the coils.

AIR CONDITIONING COMPRESSORS ON GASOLINE/ELECTRIC HYBRID VEHICLES

Toyota has taken the electric-drive ap proach. The second generation Toyota Prius, starting in 2005, takes additional advantage of the high voltage system used in their gasoline/electric hybridvehicles by using an electric motor with an integrated inverter and controls to drive the air conditioning compressor. The air conditioning compressor is integrated with a high voltage, 3-phase AC motor and control inverter. All other Toyota and Lexus gasoline/electric hybrid vehicles produced also use this same type of air conditioning system.

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