166 aircon

[alfagtv152]

Hi Guys,
What is the general consensus on 166 air conditioning efficiency,I had mine serviced and regassed last friday week but today it was 36 degrees and the air con was poor.The air con tech made a good point in that the radiator fan only runs on the pressure switch not when the clutch is in on the compressor which makes it very in efficient in traffic so I will be changing that tomorrow.
The other issue I am weary of is that the interior fan seems to draw very high current,it requires a 30 A fuse to  stop it blowing on full speed and has melted a fuse in the past,I have now fitted a circuit breaker for the fan,15 A held up ok except for flat out speed.One of the other 166 owners here said today his was not very good either even after spending money on it.
Cheers
Andrew

[colcol]

The pressure switch is usually a high / low, when the compressor pressures get too high, its cuts out the power to the compressor, and when its too low, ie a leak, it cuts out power as well, the compressor is switched on by the TX Valve, when you get the airconditioner regassed, make sure the system is vacummed down so that it gets all the moisture out, as this can cause poor performance in hot weather, as the moisture blocks the orifice in the TX Valve, the fuse blowing is a concern, it sounds like the blower motor has a short in it, or it has seized up fan bearings, putting a load on the fuses, you may have to take it to an Alfa Romeo specialist who knows these cars, and would have dealt with this problem before, Colin.

[alfagtv152]

Hi Colin,
Thank you for your reply but as I said the pressure switch does a lot on these cars. It is a 4stage pressure switch which contolrs the radiator fan for high and low speeds as well as airconditioning functions. After fitting another 50A relay to turn on the radiator fan at full speed when the clutch engages I drove over to aircon techs place where I had it serviced and recharged(yes vacced down to) and the retired father of the bloke who did it last time was there,he checked it over and it was only getting 15 degrees out of the vents even though the gas was ok. His suggestion was to remove the gas that was in there and refill it with 134A refridgerent because the son had filled it with the latest replacement for 134A !!!!!!!!!,the new stuff didn't run suitable pressures for the Alfa pressure switch&system. Once it was recharged with 134A it produced 5 degrees out of the vents.
I couldn't quite tell the number of this new gas was but I am sure somebody will know.
My recommendation is to stick with 134A if you can, otherwise you will need to modify the system with what will be a retro fit system later on for the new gas.
Cheers
Andrew

[colcol]

IF the airconditioning mechanic, was a qualified VASA, [Vehicle automotive systems airconditioning?], then he would have most likely used the correct R134, as he would have been licenced to buy it, when you deal with backyarders, [like me], who havn't got a ticket, then they can only buy replacement gasses of Ebay that have differing results, some replacement gasses are OK, some are rubbish, like the one i purchased over the counter for my 33....., don't get me started, one of the many problems with 'drop in replacement' gasses is that the chemical content can mix with the old gas and oil and seals and hoses and form an acid that corrodes everything in your aircon system, there is no need to use any other gas in a modern car than R134, on the older cars you need R12, which has been illegal for about 20 years, for all the new cars in about 2014 there is a replacement gas coming, which has a shorter lifespan than the current gases in the atmosphere, that only damage the ozone layer for a few years, unlike the current gasses which do damage for hundreds of years, Colin.

[alfagtv152]

Hi Colin,
Yes he has all the acreditations etc and aircon is his specialty,he has several machines which do different gases so they do not get mixed and he even has a machine which he hooks up to analyse the gas before he starts so he can not contaminate his gases. Definitely not a back yarder. He told me the cost difference between R 134A and the other gas that is trying to be introduced in it's place and it was considerable,this change is driven by environmental concerns as it is a green house gas not a CFC like R12 or R22.
So just to be clear he did not put in R 134A in the first instance even though that is what was taken out,and vaced down.
After not working correctly he once again removed the gas with the correct machine for that gas and vaced it down, then he connected the machine for R 134A and vaced and recharged it with R 134A which worked pretty good.
The only thing I can not give you at the moment is the number of the other gas which I can find out if you want,I think it may have been HC12a.
With a bit of searching on the internet as you say there are lots of so called drop in gases with lots of testimonies of how good they are.
Have a look at this    http://bennettsupply.net/HC-12a.htm
Cheers
Andrew

[colcol]

Because 156's and 166's don't have the best airconditioners, i would always put in R134, just so its working at 100%, and its not going to damage the aircon unit, [ imagine the cost of replacing it], the gas that i used as a drop in replacement R12 for the 33 was terrible, the compressor ran all the time, and didn't cool, i tried it twice on my 33 and once on a VL Commodore i had, the technical reports said it was better than R12 and the testimonials said how good it was, and i put it in, only because i couldn't get any R12, the new gas i was talking about hasn't come out yet, expect them in the new range of 2014 cars, i did a post on it about 3 months ago, i think in the off topics section, Colin.

[Alfa166]

The 166 has much better air-con performance than a 156 , i would look at the upgrade of the combined thermo-fan and possibly a better condensor. Alot of the performance of Italian air con is because of the pissy little condensors they fit to them.

[colcol]

Its the size of the vents in the 156 that let it down, the series 2 & 3 156 had the same dual climate control system as the 147 and compressor, condensor, evaporator, but the 147 has bigger vents and flows more air, i have found it is more important to flow air, rather than have a bigger aircon, sometimes the airflow is so poor, the evaporator can freeze up, Colin.

[alfagtv152]

Hi Guys,
Just a bit of an update,with the fan on fast whenever the clutch is in on the compressor and leaving it in manual mode it has been really good so far.
Cheers
Andrew