E30 air con issue too hot or too cold !!

[mrporsche]

Evening,

I have had it re-gassed and it blows icy cold.

However If you turn the dial just a small amount it then blows at full heat. I can either have minimum or maximum.

When I have had the fan on a car fail it is either no fan or on 5 for full fan but nothing in between.

That was a simple resistor, is this the same or do I need to replace the entire control unit

Thanks

[fixedwheelnut]

Is it standard Air con or a Diavia style aftermarket one?

E30 didn't have control units for A/C so the fan will probably be the resistor if it is only working on full speed, check the fan motor bearings too as they start to seize up and draw more current burning the resistor pack out. free them off with some three in one oil
There should be a temperature probe going in to the A/C evaporater behind the dash that will be adjustable, they should be adjusted so that the compressor cuts in and out hovering the evaporater temperature between zero degrees and plus four degrees

mrporsche said:

Evening,

I have had it re-gassed and it blows icy cold.

However If you turn the dial just a small amount it then blows at full heat. I can either have minimum or maximum.

When I have had the fan on a car fail it is either no fan or on 5 for full fan but nothing in between.

That was a simple resistor, is this the same or do I need to replace the entire control unit

Thanks

[mrporsche]

fixedwheelnut said:

Is it standard Air con or a Diavia style aftermarket one?

E30 didn't have control units for A/C so the fan will probably be the resistor if it is only working on full speed, check the fan motor bearings too as they start to seize up and draw more current burning the resistor pack out. free them off with some three in one oil
There should be a temperature probe going in to the A/C evaporater behind the dash that will be adjustable, they should be adjusted so that the compressor cuts in and out hovering the evaporater temperature between zero degrees and plus four degrees

[

Morning,

thanks for this.
As far as i am aware it is standard - certainly looks it.

The fan is fine.

Do you think the heating working only on full heat is related to the temperature probe or the unit itself ?

As you live in the South East, perhaps i could call on your hands on expertise....

Thanks

[Locknut]

Fixedwheelnut has set it out well, the only thing I would add is to do the easy thing first. So start with the fan bearings and the resister pack, and leave the other things until later.

My money would be on the resister pack. Every car has one whether it has A/C or not, and it is a common failure point. I recently had to change one on my wife's Fabia which is less than four years old.

[ian332isport]

It sounds like you have a problem with the mixer flaps rather than the fan.

When you turn the temperature control fully counterclockwise, there's a switch that tells the main heater valve to close which stops the flow of hot water through the heater. When you turn the temperature control clockwise, by more than 20 degrees, the heater valve will open. You now have hot water flowing through the heater. Your description seems to follow this pretty well.

It's the responsibility of the air mixer flaps to blend the cold air from the evaporator, with hot air from the heater matrix, to adjust the overall temperature in the car.

How much control of the temperature do you have with the A/C turned off?

[fixedwheelnut]

mrporsche said:

Morning,

thanks for this.
As far as i am aware it is standard - certainly looks it.

The fan is fine.

Do you think the heating working only on full heat is related to the temperature probe or the unit itself ?

As you live in the South East, perhaps i could call on your hands on expertise....

Thanks

Where are you in the South East not that we can do anything in the middle of Tier 4?
If the Blower motor only works on speed four then it must be the resistor faulty which probably means the bearings are tight too.

If you are only getting heat on speed four but speeds one to three blow but only cool air then this is probably a mixing fault which may be cable adjustment or a fault inside the heater box [not fun]