heat with air-con only !!

[Moogwai5]

any ideas anyone, my 172 has decided not to issue any warm air unless the air conditioning and auto is on or its set to maxi without it, for example set to 21 without auto on and it blows cold air!?

Perfect time of year for it to happen!! Also when on auto the air con is on permanently and the power of the blast seems rather high and when I select the windscreen function it seems rather low (usually blasts it out at full wack but now only about 50%)

plus dont know if this has anything to do with it but my external temp sensor has gone on the blink 47c outside dont you know!!

 

[KDF]

sounds like the inside air temp sensor is broken, when on max it will ignore inside air temp as its not trying to set a specific temprature, just to chuck out as much heat as possible.

I think, but dont quote me on this.. that the inside air temp is in the interior light fitting, you will see that there are slits in it like a small speaker could be there.. anyway I think the sensor must be in there as it would make sense to have it there.

 

[Moogwai5]

I can see where youre coming from but why would there be heat then with air-con on ??

 

[KDF]

I can only assume that it has to use some other method of detection when using air-con + heat. Like a temp sensor in the air-con system. It must have as people say the air-con wont come on if the outside temp is too low.

 

[Moogwai5]

hmm makes more sense



guess Ill have to talk the brother in law tomorrow (Ren Mechanic) and get her fitted in.

 

[chris_leic172]

My climate control was playing up, changing the air direction buttons wasnt changing the airflow. Ended up having a new climate control computer which sorted it.

 

[RS-Steve]

my a/c wouldnt come on earlier an the temp outside was 0c. does ant1 know why?? the blowers werent on 100% either or they didnt sound it, i just pressumed it was cos its not bin started all week an everything was settled in the a/c system?

 

[Gambler]

the aircon came on mine this morning when i blasted the windscreen !!!

 

[JAY172]

the sensor near your interior mirror is a humidity sensor so the computer can regulate the aircon/heating to give the perfect amount of air humudity inside the car(humidity is how much moisture is in the air).the aircon wont work below zero because the tempurature sensor on the evaporator will show the computer its already cold(if the aircon is turned on at such low tempuratures it could freeze up the evaporator).i dont think the sensor that is for the dash display has anything to do with the aircon operation.sounds like the aircon panel/computer is acting up.the aircon panel is diagnosible with the renault diagnostic equipment so its easier to find faults than on the standard aircon system.

 

[KDF]

Cool, so if there is a humidity sensor next to the rear view mirror, what is the other one ? i mean there are 2 sorta cutout bits which would indicate 2 sensors ?

 

[JAY172]

the humidity sensor sucks air through itself using a little fan.the 2 cut outs are probably the in and out of the sensor.