Heater / Aircon Controls - What does what

[Swiss_Toni]

Sorry for the dumb question however.....

Under the dash there are 2 rotary knobs and push pull knob. What does what?

I'm off this morning to get the Aircon serviced and I don't want to look like a.... knob:-)

[GTRCLIVE]

One is for heater fan speed and the other is the Thermostat for the AC. If running the AC make sure you turn off the heater with the old choke pull cable under the dash.

[Steve_D]

The knob nearest you controls the blower fan speed and is three clicks clockwise.
The knob furthest from you controls the A/C temp and is a click clockwise then variable.
The A/C does not work unless the fan is on at least the first speed.
The pull out control is the heater water control valve and will give variable control of the heater temp but is not an easy control to use as it is a bit on/off.

Steve

[Swiss_Toni]

Great,

Just to make sure, for the heater the "choke" cable IN is heat OFF and therefore used with AC?

Greg

[Steve_D]

Swiss_Toni said:

Great,

Just to make sure, for the heater the "choke" cable IN is heat OFF and therefore used with AC?

Greg

Yes

[AlexCim]

Steve_D said:

The knob nearest you controls the blower fan speed and is three clicks clockwise.
The knob furthest from you controls the A/C temp and is a click clockwise then variable.
The A/C does not work unless the fan is on at least the first speed.
The pull out control is the heater water control valve and will give variable control of the heater temp but is not an easy control to use as it is a bit on/off.

Steve

When you say controls the A/C temp, what do you mean?

I would have thought it would be A/C on or off, with variable fan speed and you would adjust temperature (both A/C on or off) with the pull out knob that adjusts more hot water into the heater core for higher temps.

Is there a way I can just hardwire the A/C to always be on if I have the blower on? When I adjust the A/C "temp" I can hear the compressor turning on and off.

[Steve_D]

AlexCim said:

When you say controls the A/C temp, what do you mean?

I would have thought it would be A/C on or off, with variable fan speed and you would adjust temperature (both A/C on or off) with the pull out knob that adjusts more hot water into the heater core for higher temps.

Is there a way I can just hardwire the A/C to always be on if I have the blower on? When I adjust the A/C "temp" I can hear the compressor turning on and off.

Just as I said. Provided the fan is on at least low speed then the A/C will work when you turn the control knob away from the click off position. As you continue to turn the knob the temp should be lower.
Not sure why you would want the A/C on all the time you have heating on. There are some demist situations but not all the time.

Steve

[UltimaCH]

Steve_D said:

Just as I said. Provided the fan is on at least low speed then the A/C will work when you turn the control knob away from the click off position. As you continue to turn the knob the temp should be lower.
Not sure why you would want the A/C on all the time you have heating on. There are some demist situations but not all the time.

Steve

Alexcim is down under when reading his profile details, so I imagine it can get pretty hot in his part of the woods...

[AlexCim]

My fan (over the condenser) runs at a fixed speed regardless of what setting I put the AC knob on. What exactly does the AC temp knob adjust as my understanding is that the AC compressor runs at a fixed speed (off the belt) as soon as the clutch is engaged. Or does it just adjust how often the clutch engages?

I get hot in my car on a 25 degree and sunny day. I checked the pressure and gas and it all seems fine so I am investigating other ideas.

[F.C.]

AlexCim said:

Or does it just adjust how often the clutch engages?

This is correct!

[F.C.]

While on the topic of air con.
Does anyone have an aftermarket control set up that can be mounted in sight?
I can use a remote electric valve and probably adapt the other two knobs to go through a front (facing driver) panel but a small electronic/electric display type thingamajig would make things neater.
Any help would be appreciated I am going under the dash to do some work soon and while I have the seats out it would be good to do this at the same time.
Something along these lines perhaps?

http://www.ebay.co.uk/itm/Digital-Climate-Controll...

[Abbosevolution]

F.C. said:

While on the topic of air con.
Does anyone have an aftermarket control set up that can be mounted in sight?
I can use a remote electric valve and probably adapt the other two knobs to go through a front (facing driver) panel but a small electronic/electric display type thingamajig would make things neater.
Any help would be appreciated I am going under the dash to do some work soon and while I have the seats out it would be good to do this at the same time.
Something along these lines perhaps?

http://www.ebay.co.uk/itm/Digital-Climate-Controll...

+ 1 on this - I have a remote electric valve but an not at all happy with the options in how to adapt the two knobs to look anything like the rest of the buttons on my dash - would like something that looked up to date - anyone got any ideas

[Steve_D]

AlexCim said:

My fan (over the condenser) runs at a fixed speed regardless of what setting I put the AC knob on. What exactly does the AC temp knob adjust as my understanding is that the AC compressor runs at a fixed speed (off the belt) as soon as the clutch is engaged. Or does it just adjust how often the clutch engages?

I get hot in my car on a 25 degree and sunny day. I checked the pressure and gas and it all seems fine so I am investigating other ideas.

The A/C knob is reading a sensor on the side of a valve on the side of the evaporator. Depending on the setting and the temperature it switches the compressor in and out.
The condenser fan is fixed speed.
If you want the A/C on all the time then just leave the A/C knob in the full cold position. The A/C will go off if you switch the three speed blower off.

I think the main issue you will have is that the system could do with being a little larger. OK in the UK but not 'down under' or parts of the US.

Steve

[F.C.]

Steve_D said:

AlexCim said:

My fan (over the condenser) runs at a fixed speed regardless of what setting I put the AC knob on. What exactly does the AC temp knob adjust as my understanding is that the AC compressor runs at a fixed speed (off the belt) as soon as the clutch is engaged. Or does it just adjust how often the clutch engages?

I get hot in my car on a 25 degree and sunny day. I checked the pressure and gas and it all seems fine so I am investigating other ideas.

The A/C knob is reading a sensor on the side of a valve on the side of the evaporator. Depending on the setting and the temperature it switches the compressor in and out.
The condenser fan is fixed speed.
If you want the A/C on all the time then just leave the A/C knob in the full cold position. The A/C will go off if you switch the three speed blower off.

I think the main issue you will have is that the system could do with being a little larger. OK in the UK but not 'down under' or parts of the US.

Steve

I had heard of someone doubling up on the condenser unit stateside with good results, I have an idea one condenser was moved up front to the rad area.

[UltimaCH]

Yes, I'll see if I can find the thread...