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Old 28th May 2020, 16:03   #21
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Originally Posted by GP1005 View Post
Low speed fan on initially and switched to high speed once there was enough pressure in system
It's switching to high speed due to over-pressurisation. The low speed should run continuously and not switch to a higher speed. Your aircon man didn't do a proper job. Go back to Post12


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Old 28th May 2020, 16:05   #22
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Originally Posted by T-Cut View Post
That's a fail for the Demist Test. The low speed fan should run continuously until the aircon is turned off. If the fan speed changes to high speed, then the system is over-pressurising. That may be due to lack of condenser capacity, typically from a degraded matrix.

This from Jules I believe.



Worth looking into - or through as the case may be.


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Old 28th May 2020, 19:19   #23
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That be Paul (Reebs) TC
Yes, I understand it was taken at Jules' place. (?)


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Old 28th May 2020, 20:13   #24
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so when should fan speed 2 activate in the air-con cycle ?
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Old 28th May 2020, 20:25   #25
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Thanks for the comments

TC - I have run the demist test again with a cool engine at tickover.
Fan off. Pushed demist and fan on full until switched off again by pushing econ (test you recommended in 2014)

Chuckles - can you change/check the desiciant without regas

SD1too - Sadly Ashford, Kent and not Ashford, Middlx
As far as I know, you can not change the desiccant pack without degassing.
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Old 29th May 2020, 06:36   #26
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so when should fan speed 2 activate in the air-con cycle ?
In very hot conditions when the air conditioning is working hard.

Following removal of your refrigerant, was the system evacuated for half an hour before recharging? Was the condition of the condenser checked?

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Old 29th May 2020, 08:25   #27
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There was very little gas left in the system. It was vacuumed for about 30 mins. Difficult to inspect the condenser without removing the bumper which was not done. A dye was added.

What are the implications of an over-pressured system ? There is plenty of cold air at the moment.

Gary
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Old 29th May 2020, 12:14   #28
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As far as I know, you can not change the desiccant pack without degassing.
Note for info. I've just gone through much of the mechanical bits of this job - replaced the condensor and both O rings and with the help of a local mobile AC man on the de-gas/re-gas etc. = £70 including a pressure check on Mrs. H's Jazz (looks like the Honda condensor is goosed too..).
New bits purchased off DMGRS, the condensor was very well packed but arrived bowed which I sorted with some gentle straightening on a flat wooden surface.
The the aluminium condensor is supposed to be 'OEM' (made in China) which I'm not challenging but the dryer dessicant cartridge is now welded into it's housing so for all general purposes cannot be replaced; if it later goes U/S then it's either no AC or (yet) another new complete condensor.
Not had a good run yet so I'll comment later if appropriate.
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Old 30th May 2020, 09:58   #29
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Difficult to inspect the condenser without removing the bumper which was not done.
Gary; you can see the condenser through the grille and the slats at the bottom of the bumper moulding. I think that with the engine undertray removed you can get a view from below but don't quote me on that!
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What are the implications of an over-pressured system ? There is plenty of cold air at the moment.
The system is only over-pressurised if the high pressure trinary switch disengages the compressor. An increase in fan speed is normal if, for example, you return to a car with an uncomfortably hot interior which the air con. is trying to cool to, say, 19 degrees. I'd also expect it to happen with an ambient temperature in the upper twenties when the engine is hot and the car stationary or slow moving.

You'll know what the conditions were when you tested it. I'd recommend keeping it under observation. After a few minutes' running with 'LO' temperature and recirculation selected, the air temperature out of the centre vents should be approximately 4 degrees C.

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Old 13th July 2020, 20:02   #30
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Hello colleagues.
I have one question about air conditioning. I was at refilling the medium and during filling the device showed too high pressure.[/IMG] (22 bar, 7-17 bar is normal)

The first serviceman told me that my fan does not spin much (I have a gold resistor and during the demist test the fan rotates normally)

The other serviceman told me I had a broken compressor.

And the third told me that high pressure is ok, that it will return to normal.

The air conditioning was cooling, the fan was spinning.
Again, I think I have a broken condensator.
What do you think?
Thank you.
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