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Discussion Starter #1
Can someone help?
My heating system in auto is not working properly. The ac compressor is always in function even if the outside is cold and I move the heating comand at full red.
The inside temperature is warm enough.
Nevertheless, if I choose Econ I'm the switch, the inside temperature is getting wormer.
Is this normal?
Thanks all
 

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Can you please post your SZ Chassis Number Derivation from VIN?

I do not believe that Crewe ever changed how the system worked (at least not until the Seraph/Arnage era cars, if then) but for the Shadow era cars the air conditioning compressor is always on unless the outside ambient temperature is below freezing (32° F/0° C). The air is always cooled first to remove humidity first then warmed (if appropriate) so that the cabin temperature can be maintained at the level you've set using the dials.

In my 1978 Silver Shadow II the compressor never even cycles on and off. I know that this did change later, but that you'll still have the compressor cycling unless the outside temperature is below freezing.
 

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What year is your car? I know you'll be DA?-24750, but at least I know we're dealing with a 20K series car.

It's not surprising that the temperature might climb a bit higher in ECON mode. In ECON mode the a/c compressor function is disabled. Heating ambient temperature air (when the temperature is reasonably warm) is a lot easier than heating pre-chilled air. Also, in ECON mode there is no way for the car to as carefully modulate temperature if it needs to bring it down a few degrees. It's only got "cold" that's at ambient air temperature; the less the differential between ambient and dialed in the less quickly the system can adjust for overshooting the target just a bit.
 

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Discussion Starter #5
Thank you. Car is 1988.
As I read in other posts, the heater matrix should be functioning since in defrost the temperature is pretty hot. But, when I use the comands, even at full red, the temperature is never as hot as it is in defrost.
How can I check if the heater tap is functioning?
 

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If you've got full blast heat in "Defrost" mode then the heater tap is working. There's only one and it is what regulates the flow of water in to the heater core (well, along with the actuator for the tap). Where the air comes out is all mixing flaps.

It is not surprising that "full heat" is not as hot as "full defrost." Full defrost is supposed to be a full frontal assault of dehumidified and heated air blasted on to the windshield (and, unfortunately, is like that if you're trying to just get rid of a bit of a summer fogging on the windshield rather than a sheet of ice in the winter).

The heat, on the other hand, is regulated for human comfort and I have yet to be in a car, even a cold one, where the heat output from the heat is nearly as intense as the heat output in "Defrost" mode.
 

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Discussion Starter #7
Thank you very much.
One final question. I believe the engine is not hot enough. The temperature gauge in winter never rises the half. My auxiliary fans start at 60 Celsius. Could this be the reason of a mild hot air?
Moreover, in a Spur 1997 i owned, when cold, the air started to come out only when the engine was warm (few minutes after running the car) in the corniche the air comes out soon and naturally at the beguinning is cold.
Did u see my post on cruise control?
Thank you again and happy new year
 

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Alberto,

It would not surprise me one bit if you have a thermostat that's either become stuck open or lost its lead pellets or both. Read the article, Thermostat Issues and Selection (I am the third author).

I did see you post on the cruise control but:

a) your description of what's wrong "not smooth" is far too vague to be able to venture any guess as to what could possibly be going on

b) is not an area within my realm of expertise (or at least the repair of it isn't. I'm working with a cruise issue on my Shadow II).
 

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Discussion Starter #9
Tks. Your article on thermostat is very interesting and I have ordered a new piece of the newer generation.
As far as the cruise, I meant sometimes the car goes like having hiccup, sobbing yet non changing the set speed.
 

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I have the same issue as Alberto had. My Corniche II does heat only when the roof/head is up. If i open the roof/head then there is only cooling, with or without a/c, so no more heating if the roof/head is down. My S/N is 29100.

I guess there is a sensor not working if the roof is down.

Has anyone any idea?

Thanks for any help, Tom
 
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