With the top up canisters, even if you do actually get real R134a (and how would you know) the content weight is never what is advertised and what can be drawn from them is a lot less than the actual contents anyway, the more you put in the higher the system pressure the less you can get out of each can.

 

You will however have your own personalised hole in the ozone layer!

If you gassed it from empty without pulling a vaccuum there will be maybe 25% air mixed with the refrigerant although I dont think it would then reach 11 bar high side.

11 hours ago, JoeF said:

Should they both be spinning at the same time?

Sometimes.

 

If the car has A/C, then the LH side fan should be on low whenever the A/C is on (or all the time with Climatronic). The RH fan and LH high speed mode will cut in and out as required.

11 hours ago, Wino said:

Both fans should switch over to full speed if refrigerant pressure gets too high with just the small fan running at low speed, see if this happens after a while at a standstill. If it doesn't, check the strip fuses above battery.

 

You can watch refrigerant pressure in one of the HVAC measuring blocks. 9 bar threshold for low speed fans, 16 bar for full speed, from memory.

 

Catch you tomorrow.  

Forgive my poor diagrams but could I splice the low power side into the high power side before the resistor with out it causing any real issues?

 

(I am assuming that is how the motor is wired up)

Edited 1 June, 20215 yr by JoeF

17 minutes ago, KenONeill said:

Sometimes.

 

If the car has A/C, then the LH side fan should be on low whenever the A/C is on (or all the time with Climatronic). The RH fan and LH high speed mode will cut in and out as required.

Are you counting the left hand fan as the small one almost directly in front of the aux drive belt? Mine kicks in 60 seconds or so after you turn the AC on.

1 minute ago, JoeF said:

the left hand fan

is, amazingly enough, the one on the left side of the car, hence the name "LH side fan".

Left hand looking at the car from the front or back though? I am assuming you mean the larger fan pointed at the engine.

Edited 1 June, 20215 yr by JoeF

30 minutes ago, KenONeill said:

Sometimes.

 

If the car has A/C, then the LH side fan should be on low whenever the A/C is on (or all the time with Climatronic). The RH fan and LH high speed mode will cut in and out as required.

Bad info in the context of Mk1 Fabia. The fans are wired in parallel, as said earlier. 

Edited 1 June, 20215 yr by Wino

40 minutes ago, JoeF said:

For give my poor diagrams but could I splice the low power side into the high power side before the resistor with out it causing any real issues?

 

(I am assuming that is how the motor is wired up)

 

That's a good diagram!

Yes you could. The relay and its fuse for the low speed action won't quite be rated to run main fan at high speed and other fan at low, but I bet it'll work OK in the short term.

 

The circuit for the fans is like this:

 

9 hours ago, KenONeill said:

Sometimes.

 

If the car has A/C, then the LH side fan should be on low whenever the A/C is on (or all the time with Climatronic). The RH fan and LH high speed mode will cut in and out as required.

Just out of curiosity Ken, I had a look at some Octy 1 A/C circuits, and the fans' wiring appears to be parallel too.

If yours work as you describe, there may also be a fault with low speed function in one or other fan, depending on which lefts and rights you meant.  

Edited 1 June, 20215 yr by Wino

1 hour ago, Wino said:

Just out of curiosity Ken, I had a look at some Octy 1 A/C circuits, and the fans' wiring appears to be parallel too.

If yours work as you describe, there may also be a fault with low speed function in one or other fan, depending on which lefts and rights you meant.  

Thanks for the thought.

All this talk about two fans just got me thinking, I have air-conditioning, I've never experienced overheating in my 2007 Fabia, and it's routinely between 35°C and 40°C where I live. 

 

My car only has one fan. It mostly runs at high speed after the A/C is turned on. I can count on one hand the times I've seen it running at low speeds.

 

Fan kicks in high speed when coolant temperature reaches 100°C according to VAGCOM, but I've never seen the gauge move ever so slightly over 90, not even a fraction of a millimetre.

 

 

And A/C works flawlessly!

Edited 2 June, 20215 yr by juanse_2691
Clarification

My spare Polo (2005, BKY engine, with A/C) has only one rad fan, despite its cooling needs being seemingly identical to my 2003 BBY with A/C. I guess the single fan is probably slightly larger and maybe more powerful than the larger one in the dual fan set-up, but haven't checked. Cost cutting I guess?

 

It does make the system less fault tolerant. When I acquired it, the low speed function on it was non-functional due to the 'traditional' burnout of the internal resistor, and high speed couldn't be triggered by radiator temperature because one of the thermoswitch wires had broken.  I think it must have only been used for short local journeys, because it was very vulnerable to overheating in that state. A/C hadn't been fixed when reported empty several years ago according to service records. Reminds me, I have a couple of o-rings to change on that, which could be today.