HDI cooling fan runs at engine start up - never used to..!

[pugface406lx]

Hello Guys,

Ive got a 2.0 HDI W plate....problem started with no gas in air con system, had it filled no probs.... 3 weeks later low on gas so I called Air con Man back and he confirmed its leaking out somewhere.....checked it over, cant find leak yet so hes put more gas in with a dye in the oil to wait for the leak to show again.

Thats fine but now on start up the cooling fan trips in for about 10mins of running then switches off
It never did this before he fiddled with it...BUT he did spray some washing up type liquid all over the condensor and the pressure switch and found no obvious leak...im wondering if its the pressure switch.
Baffling as I have another HDI and the fan doesn't trip in like that and more alarming it was fine before ...apart from air con losing gas of course..!!

Any Thoughts welcome.

cheers
Pugface

[mjb]

If the fan running at full pelt or half speed?

It's normal for cars with ac on to continually turn the fans on and off when stationary in order to remove heat from the condenser (located by the radiator)

[Welly]

so I called Air con Man back and he confirmed its leaking out somewhere.....checked it over, cant find leak yet so hes put more gas in with a dye in the oil to wait for the leak to show again

That is completely irresponsible of the a/c man he's not allowed, by law, to put refrigerant into a system without FIRST confirming (under a high pressure nitrogen test = 250bar ish) that the system is sound. You can actually get sentenced to prison for refrigeration offences.

This is why those halfords kit's are so annoying to professionals because there must be so much refrigerant being pissed out all over by car owners 'having a go' at fixing something they know nothing about

He may now have over-gassed it or wetted/shorted the pressure switch or something to make your fan run like that. As you say...it was ok before hand

[puggy]

I think you will find when it ran low on gas the reason the fan was not working
the pressure switch was doing its job and shut the system down then when he topped it
up it started to work normal as mine does. In this weather when i start my car the fan
kicks in straight away after pulling off and cool air starts to flow through it starts to switch
on and off depending on if i am moving or not, as mj said they are designed to cut in and out
depending on demand .