Hi everyone.

Just had service on my z at nissan,i asked them to regas my z but could not as its a 1992 and the gas is discontinued,so i took it to a specialist who refilled it with a like for like gas cost 120 pounds.

But now the air con fan dosent come when in traffic so ive linked across the relays so the fan comes on all the time.

Anyone else experienced this?

Its not technically an aircon fan, its the emergency cooling backup fan and it should not be coming on at all under normal circumstances.

 

Disconnect the relay link, not required.

ok thanks

Well I beg to differ with the actual fan purpose, the fan does have the secondary role of providing additional cooloing in the event of an impending engine overheat but its primary roll is to pass air over the aircon condensor when the vehicles forward movement is insufficient to pass air though the condensor ie: in traffic

 

When this occurs the pressure rises in the system in direct relation to the refridgerant temperature, the high pressure switch in the system then triggers the relay to the electric fan, as the refridgerant temperature lowers the fan goes back off.

 

All air con systems have this fan, its essential as if the refridgerant temperature is not controlled the system pressure will rise to bursting levels(22+ bar) in fact in the case of a failed fan there is an emergency blow off valve in the system that dumps the refridgerant and hence the dangerous pressure in an instant.

 

The fan not running after using a drop in gas is very common and caused by a couple of factors, one is the fan switch is not totally compatible with the new gas, and also the system cannot be filled to the same level as with the original gas, this means the running presures are lower but so is the cooling unfortunately, but then the "drop in gas" is a work around really and to be honest is more than adaquate.

 

My advice would be to re-connect the fan relay to be triggered by the air con relay or you run the real risk of the emergency valve blowing off if caught in a long traffic jam with the air con going and dumping your new charge, done this mod many times and works just fine.

 

Jeff TT

Im not aware of the pressure switch relation to the Sub fan, nor is the service manual, and never seen seen/heard the fan come in on any Z that has acceptable engine coolant temps.

 

As far as Im aware the fan operation is Enging coolant temperature and road speed controlled only, where it basically doesn't come on unless temp is above 90c with aircon on and over 105c with Aircon off. NA has 1 speed and TT has high and low speed controls.

 

If Jeff is correct then I apologise for incorrect info.

Edited April 18, 201015 yr by Yowser