A/C out and heater in

[Fosworth]

Not sure if I will be shot down for doing this to my 76 280Z. As I live in the North East of England an A/C system is not on my list of needs so I have stripped the entire system out ( it didn't work anyway ) and replaced it with an aftermarket unit. It is less than a quarter the size of the original unit and has a proper water matrix plumbed into the engine coolant system with a 3 speed fan. This one is from 'Car Builders Solutions'. I am waiting for the air ducting to arrive and then refit the dashboard so I can make up some simple controls. There certainly is a great deal of space under the dash now. The other bonus is the large amount of A/C stuff under the bonnet that I have also stripped out so now the engine bay looks looks much neater.

 

[Mark N]

I've always looked at an OEM AC system as being a great selling point, especially with one of the biggest potential markets for LHD vehicles being in continental Europe.
Personally, if I wanted to delete the AC, I would have just removed the compressor, condenser and drier then stored them away, to be refitted if desired.
The OEM control unit already has a heater matrix fed from the cooling system and the OEM controls would have retained all the functionality with the exception of providing AC cooling.
The only thing that would have to be retained in the engine bay would be the vacuum tank and solenoids.

 

[Fosworth]

I've always looked at an OEM AC system as being a great selling point, especially with one of the biggest potential markets for LHD vehicles being in continental Europe.
Personally, if I wanted to delete the AC, I would have just removed the compressor, condenser and drier then stored them away, to be refitted if desired.
The OEM control unit already has a heater matrix fed from the cooling system and the OEM controls would have retained all the functionality with the exception of providing AC cooling.
The only thing that would have to be retained in the engine bay would be the vacuum tank and solenoids.

Yes, I agree with your point of view but I have a racing background and can't bear to carry such large amounts of unnecessary weight around. With all the A/C stuff and the US bumpers ( & mounts ) all gone the car is so much lighter. In fact all that is about the same as an adult passenger !. The result is better performance, braking and fuel economy and I don't intend selling so am not worried about that aspect.

 

[Mark N]

I fully agree that the federal bumpers should be the first thing to go!
I was only suggesting that you could still lose the bulk of the unnecessary weight by just removing the AC compressor, condenser and drier.
All you have really gained is the loss of weight difference between the OEM control box (plus the plastic vacuum tank) and the CBS one, which would only amount to a few kg.
Unless you are planning some elaborate ducting system to direct the air, at a cost of more weight, you will have the DEF vents running constantly (when the fan is on) and only have the option to open/close the side ball vents, which is a fairly large loss of system functionality.

 

[Fosworth]

Sadly I didn't weigh the bumpers, compressor, crazy thick mounting bracket etc, etc but I have just weighed the under dash A/C unit and it comes out at 18 kgs, the new heater is 1.7kgs and there will only be two vents to the screen so that is a big saving. I also run a Pre airflow MK1 Cortina and that is so primitive the air only flows ( as the name suggests ) if you open the rear windows and I don't use the fan very much with that. I find that totally adequate for my use of the car so I am confident my aftermarket unit in this application will do all I want. I am very old school ( by age ! ) so am at ease with simpler things but I fully understand that others like to have all the facilities of a full A/C based system, it just isn't for me.

 

[MCBladeRun]

Hi Fosworth, I was planning on an aftermarket AC unit for my 240z and was also looking at car builder solutions. Will you update the thread when you've completed the install?

Martin

 

[Fosworth]

Hi Fosworth, I was planning on an aftermarket AC unit for my 240z and was also looking at car builder solutions. Will you update the thread when you've completed the install?

Martin

Yes I certainly will but this is no A/C unit. Strictly hot or cold air !!

 

[MCBladeRun]

Yes I certainly will but this is no A/C unit. Strictly hot or cold air !!

Ah I see. You're replacing the heater matrix and removing the heavy a/c components?

 

[Paul_S]

There is also this thread on a similar subject --> https://zclub.net/community/index.php?threads/run-without-heater-and-blower.26928/

 

[Fosworth]

There is also this thread on a similar subject --> https://zclub.net/community/index.php?threads/run-without-heater-and-blower.26928/

Many thanks for the link to the other thread. In my haste I overlooked the need for a heater valve but now it is ordered and will be fitted asap.

 

[Fosworth]

Just an update on the aftermarket heater. I've now fitted all hoses and trunking and am very happy with the result. I know it hasn't got side vents but I don't need them. My main aim was to get good demisting and that's what I've ended up with. You may be able to see the 3" duct which brings in the cold air from the original position in the scuttle.

 

[Rob Gaskin]

Just an update on the aftermarket heater. I've now fitted all hoses and trunking and am very happy with the result. I know it hasn't got side vents but I don't need them. My main aim was to get good demisting and that's what I've ended up with. You may be able to see the 3" duct which brings in the cold air from the original position in the scuttle.View attachment 42194

Looks good.

I have connected one of my 4 heater outlets to a central duct in the dash. I have connected my side vents to the fresh-air vents that originally supplied the footwell (are these on your car?).

Water hoses ok? On/off tap? Fan switch?

What are you doing with the original heater controls?

 

[Fosworth]

Looks good.

I have connected one of my 4 heater outlets to a central duct in the dash. I have connected my side vents to the fresh-air vents that originally supplied the footwell (are these on your car?).

Water hoses ok? On/off tap? Fan switch?

What are you doing with the original heater controls?

Pic shows coolant hoses ( Have got clamps on all joints now!). I haven't finalised heater controls until the dash is back in but am thinking about how to utilise the original panel. The fan switch will connect into the original wiring. I did take a whole load of A/C wiring out so it all much simpler now. Yes there is plenty of scope for other ducting but I will wait until I've tried what I have so far to see if I need more.

 

[Rob Gaskin]

Ok. Mine 'box' has the coolant pipes on the other side so much easier. So you don't have a water valve?

Are you using a new fan switch or the original? If you use the original you will to make sure you reverse the polarity in the wiring to it. It switches 'ground' to the motor in standard configuration.

 

[Fosworth]

Ok. Mine 'box' has the coolant pipes on the other side so much easier. So you don't have a water valve?

Are you using a new fan switch or the original? If you use the original you will to make sure you reverse the polarity in the wiring to it. It switches 'ground' to the motor in standard configuration.

Excellent thanks. I hadn't got round to switches yet and was thinking of originality but in view of what you say I may just use the one that came with the new heater. No valve yet but I have made provision. Thinking of just cutting airflow. It will be much easier to make these decisions once the car is on the road. My problem is that I have never even ridden in an S30 of any sort let alone driven one so there may well be a lot of decisions to make once it is mobile.

 

[toopy]

I would advise against just cutting the airflow instead of a proper valve.

Think of what's happening in the heating circuit when all airflow is cut, the heat is moving through the matrix but has no where to go and returns to the block much the same temperature. With a valve the flow is reduced/stopped and the heat is then directed to the radiator, if its a hot day and your stuck in traffic, the last thing you want is extra hot water not being cooled, plus you will still feel the heat build up radiating from under the dash if just airflow is cut.