Aircon - Quick check

This site contains affiliate links for which LandyZone may be compensated if you make a purchase.
R

Rachelkgr

Active Member
Posts
715
Location
Manchester
2001 DHSE

So as some of you know, after several years of none use, my garage reverse engineered a Pre 2000 Condenser into my car with new pipes.

Re gassed, no leaks. Ice cold on demand.

No book symbols, outside reading on screen correct, Aircon on/off button engages and disengages screechy clutch ok.

Two worries for reassurance please!

1) I fitted a replacement HEVAC unit in June, I know there are two types, wondering now if I have the right one. I assume I will have the three relays in my fuse box and may need to make a mod if I have the early one, How will I tell this? Or does the fact, the clutch is engaged on the button mean all is OK?

2) The garage said that the Aircon Fans did not run. The wiring is clean. They suspect you need an intergalacticly hot day. Is this OK?

Thanks
 
Re 1). Sounds as though it's fine.
2). The fans are controlled by pressure switches only and ambient needs to be ~ 28 C plus before low speed fans switch on, ie when ambient temps are high, A/C works harder and refrigerent pressure goes up, resulting in the low pressure switch closing and bringing on the fans.
 
davidg said:
Re 1). Sounds as though it's fine.
2). The fans are controlled by pressure switches only and ambient needs to be ~ 28 C plus before low speed fans switch on, ie when ambient temps are high, A/C works harder and refrigerent pressure goes up, resulting in the low pressure switch closing and bringing on the fans.
Click to expand...

Perfect, thanks. May have to wait until the summer for the fans test then.

:flame:
 
Rachelkgr said:
2001 DHSE

So as some of you know, after several years of none use, my garage reverse engineered a Pre 2000 Condenser into my car with new pipes.

Re gassed, no leaks. Ice cold on demand.

No book symbols, outside reading on screen correct, Aircon on/off button engages and disengages screechy clutch ok.

Two worries for reassurance please!

1) I fitted a replacement HEVAC unit in June, I know there are two types, wondering now if I have the right one. I assume I will have the three relays in my fuse box and may need to make a mod if I have the early one, How will I tell this? Or does the fact, the clutch is engaged on the button mean all is OK?

2) The garage said that the Aircon Fans did not run. The wiring is clean. They suspect you need an intergalacticly hot day. Is this OK?

Thanks
Click to expand...

the early HEVAC operated the aircon compressor clutch direct, the later one operates via a relay. If the aircon works than all is OK.
You could fit my aircon fans mod for additional cooling than you could see the fans working as they rarely operate normally.
 
Datatek said:
the early HEVAC operated the aircon compressor clutch direct, the later one operates via a relay. If the aircon works than all is OK.
You could fit my aircon fans mod for additional cooling than you could see the fans working as they rarely operate normally.
Click to expand...

Hey, sounds good. What do I need to do? Thanks.
 
There is an official LR wiring mod to convert early type HEVAC systems to a relay controlled air con compressor.

Part number YMQ104590AA if anyones interested, although you could probably make the same up for a £10 if you did it yourself.
 
MrGorsky said:
There is an official LR wiring mod to convert early type HEVAC systems to a relay controlled air con compressor.

Part number YMQ104590AA if anyones interested, although you could probably make the same up for a £10 if you did it yourself.
Click to expand...


Thanks, next time I take the dash out will look at the part number on by HEVAC and see if I need to mod it.
 
You don't need to take the dash out, it's all done under the bonnet.

I don't think you'll ever need to because you have a late model P38, and your aircon looks like it's working.
 
The relay is to ensure there is adequate voltage to the compressor clutch. Without it there is a voltage drop across the hevac ecu which means that you don't get 12v at the clutch and this causes wear in the clutch due to slip, leading to clutch failure.
 
davidg said:
The relay is to ensure there is adequate voltage to the compressor clutch. Without it there is a voltage drop across the hevac ecu which means that you don't get 12v at the clutch and this causes wear in the clutch due to slip, leading to clutch failure.
Click to expand...


Ah, ok. I get it. So I had better check the HEVAC version I have.
 
Rachelkgr said:
Ah, ok. I get it. So I had better check the HEVAC version I have.
Click to expand...
If your car has a relay in the underbonnet fuse box for the aircon compressor it requires the later HEVAC, no relay requires the early HEVAC, the two are not interchangable, there is no need to do any other checks as the system is working.:)
 
You must log in or register to reply here.

Similar threads

W
AirCon Problems L320 4.4 petrol 2005
Replies
12
Views
2K
Graculus
Graculus
E
D2 AIRCON u/s
Replies
6
Views
1K
Equinut
E
kernowsvenski
FL1 TD4 Aircon O-ring replacement
Replies
2
Views
485
andyfreelandy
andyfreelandy
T
Freelander 1 1.8 K-Series A/C Woes
Replies
0
Views
429
treadshuffle
T
Flossie
Lost me clutch, thoughts? Found the fault with a pic.
Replies
19
Views
2K
KISSMYAURA
KISSMYAURA
Back
Top