Do you use AC when you want to warm up

AdamMGEV

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So I never have AC on as I've always thought it's chemical air conditioning. I know it helps to defog the windscreen but does it so anything else? Do you ever use it when you have it on hot air?
 
Hi I just put fan and heat on full until the ice starts to melt or the screen starts to defog then take the heat back a notch or two as i think this is a drain on the HV battery. Once it has shalf cleared then turn it down to two red bars. Excìte SR model
 
A/C cools the air but also reduces its humidity so will make demisting more rapid. In commercial air conditioning systems it's quite common to chill the air before it's heated back up in order to control both temperature and humidity.
Not sure what you mean by "Chemical Air Conditioning".
 
So I never have AC on as I've always thought it's chemical air conditioning. I know it helps to defog the windscreen but does it so anything else? Do you ever use it when you have it on hot air?
Chemical Air conditioning? Maybe you are on about the refrigerant in the AC system? A/C Just uses a special substance with a weird phase change temperature to move heat around like a heat pump. The refigurent is in a (theoretically) closed system, So you will never have chemicals used up or put in the air unless your AC system has a leak.

The air con would allow you to use recirculation without fogging up the windscreen. Using the A/C WIll help reduce the condensation problems in the MG as it dehumidifies the air (that why you get a dripping from car in summer, its from the AC extracting moisture from the air)

When using auto mode, the A/C allows for a more consistent temperature.
 
Chemical Air conditioning? Maybe you are on about the refrigerant in the AC system? A/C Just uses a special substance with a weird phase change temperature to move heat around like a heat pump. The refigurent is in a (theoretically) closed system, So you will never have chemicals used up or put in the air unless your AC system has a leak.

The air con would allow you to use recirculation without fogging up the windscreen. Using the A/C WIll help reduce the condensation problems in the MG as it dehumidifies the air (that why you get a dripping from car in summer, its from the AC extracting moisture from the air)

When using auto mode, the A/C allows for a more consistent temperature.
Okay let's be clear the AC in the MG is like any car's AC and your domestic refrigerator and it has a refrigerant and a compressor pump that circulates the refrigerant around the system with a cold side heat exchanger and a hot side heat exchanger. This when operated is a heat pump that pumps heat from the heat exchanger inside the car cabin to the radiator-like heat exchanger at the front of the car just behind the grill. the pump uses surprisingly little electricity in operation and hardly in my experience has any impact on the range. However, it is very good at its job of chilling the air that is either coming into the car or recirculating through the car's heater. A very important aspect of this, particularly in humid conditions, summer or winter, and/or when recirculating cabin air is that as the air passes through the "Cold" heat exchanger excess moisture condenses and is removed through a drain pipe under the car. Better for the moisture to condense inside the AC to be removed, than on the inside of your windows and windscreen as fogging or misting. This is why when you hit the screen demist button not only does the fan speed increase as the air is directed to clear the widescreen but the AC comes on so that "Dryer" or "Dehumidified" air is used.

Regarding the "chemicals" worry of the original question yes refrigerant is a chemical but over recent years there have been made a lot safer for the environment than older style chemicals that were banned years ago, but if your AC is regularly maintained it should never be an issue. Your annual service doesn't usually include AC servicing for some reason but an AC system in my experience rarely needs anything done to it in the first 5 years when I normally go to a specialist to have a gas pressure check and I normally pay to have a fluorescent dye added. The dye helps the service engineers to check for leaks at future servicing as it glows under their UV inspection lamp. After the first service, I have only ever had it services every 2 years. There is very little you can do yourself to maintain an AC other than actually using it.

Actually, that is very important and it is usually recommended to run your AC for about 15 minutes once a week to ensure the gas and oil is circulated and the oil which is in the closed system is distributed to prevent oil from collecting in one place and prevent the compressor-pump ceasing. I always use mine in winter and in summer and with AC turned on I then just the heat control for comfort and as a result, I never suffer damp or steamed-up windows others on this forum seem to comment on.

Just for the record, there is a non-chemical means of chilling air using Peltia Electric devices. It is often used in powered Cool Boxes. It is fin for small volume cool box but is electrically very inefficient so would never be an appropriate technology for AC application in a car. There are Mini-Dehumidifiers sold using this Peltier principle and are intended to be placed in wardrobes and closets to help keep clothes fresh but they are very low power affairs.
 
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Also, along same lines as BarryH, running once in a while keeps the seals lubricated so that they don't dry out (assuming they haven't changed much in the last 15 or so years). Expensive repair otherwise.
 
IIRC, having the A/C not working can disable the whole traction system. We had a member who's car was off the road for a considerable time for this reason.
 
IIRC, having the A/C not working can disable the whole traction system. We had a member who's car was off the road for a considerable time for this reason.
That sounds a bit overkill though. Does that mean that the cooling system that is used for cabin A/C is also used for battery cooling?
 
I've never seen detailed specs but that is certainly the inference.
 
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