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The air coming out of my NB8A's a/c unit is not cold enough!
Does anyone know what the air temperature from an NB8A's a/c that is in good working order should be, please?
Cheers from slowpoke.

from what I've been told by an aircon guy, optimum temp @ the vents on any aircon is 5 deg, find yourself a temp gauge & sit the probe in your eyball vents, that will tell you what it is.

Thank you AJ I'll give that a try. Yesterday afternoon on the Hume Highway the air coming out of my a/c felt only very slightly cool, and the temp. within the car felt like 27 / 28!!?? Only slightly better than no cool air at all!
Cheers, slowpoke

That temperature is with the probe fairly deep inside the vent though. I was told 5-6 degrees is good.

I complained to Mazda about my A/C not being cold at one of the services. They said they checked all the gas pressures and the system was fully charged and working fine.

I took it to an A/C specialist and the air leaving the vents was at 12 degrees. He evacuated the system and regassed it and the temperate dropped to just over 6 degrees. He was disappointed though, he thought it would drop to 5 degrees. He commented that it might be due for a new reciever/dryer to get to 5 degrees. Though 6 and a bit degrees feels much better than 12.

NB8A a/c isn't the best

Turning it off is like cheap nos you really do notice the amount of power drain

Thanks Garry for your very helpful reply.
Any hope of giving me 'a ball park figure' of the likely cost of the regassing et al of the system, please?
Cheers, slowpoke

slowpoke wrote:Thanks Garry for your very helpful reply.
Any hope of giving me 'a ball park figure' of the likely cost of the regassing et al of the system, please?
Cheers, slowpoke

I has mine re-gassed a couple of months ago.....cost about $120

Thank you Andrew!
I'll see about getting mine checked out tomorrow.
Cheers, slowpoke

Just had mine topped up, the system is brand new but wasn't real cold, was 10 degs out of the vents. Is a bit colder after having the gas topped up (haven't put the thermometer in yet), but its 42 degs in SA at the moment & its struggling a bit!

I'm with Garry on this one.
My A/C wasn't cool either, so I took it to the local auto electrician, and he purged the gas and re-filled it, and all is now nice and cold.

The gas leaks out over time, and also gets condensation in it, so it needs to be emptied and re-filled every couple of years or so.

When you have it re-gassed, you'll also notice the smell coming out of the vents is nice and fresh too.

I'll add to the consensus, get a re gas.

Though it pays to shop around, some places wanted up to $300 (average was $200) to re gas my system and convert it to r134a as my na6 still had the old r12 gas still in it. I ended up paying $93.

Can anyone recommend somewhere to go in Melbourne (close to city prefferably)?

After recently fitting a new aftermarket compressor my temp off the evaporator is 2.1 Deg Celcius at idle, it gets colder when at the point of maximum efficiency being 2000 rpm, with vent closed it drops to 1 Deg Celcius but it is bad for a compressor if the evaporator freezes so I drive with the vent on outside air to counteract this.

Correct operation should be obtained by using Refrigerant Gauges and testing the pressures at idle and at 2000 rpm where your low pressure should read 30 psi (on a R134a gas system). My Refrigeration mechanic slightly overcharged my system and I was reading an off evaporator temp in minus figures! I went back to him last week and had a little gas removed so that my system is operating perfectly cold at idle even on the hottest days BUT to prevent liquid heading back into the compressor (a very bad thing) which occurs when your evaporator freezes, I leave the vent in the open position which compensates for what is still a very slightly overcharged system.
I have set up the air con system intentionally this way to keep the interior very cool when idling at traffic lights. I would suggest that you might want to ask your refrigeration mechanic to load the gas until you attain around 2 degrees celcius off the evaporator at 2000 rpm with vents closed - a good compromise between risk and cooling efficiency.

You will find now that with tougher regulations in force, you should not be permitted to have your system re gassed without first locating the leak that is causing the refrigerant loss, the fact is that no system should leak at all, so the thought process that all systems leak over time or that you should need a top up every summer is very wrong.
If your system has indeed leaked refrigerant and this has occurred over many years (regular top ups) then you need to find a very good mechanic who will locate and resolve the leak, when he has done this make certain you fit a fresh receiver / dryer as years of leaking will cause condensation in the system.
As I have said in another topic here on air conditioning, Australian MX-5''s (NB range) have crap "Sanden" compressors and you will find many systems over 5 years of age will leak refrigerant from the compressor seals, it will be a slow leak but ensure your mechanic checks thoroughly as a leak through the compressor will be very hard to detect - MX-5's share the same compressor as a Mazda 121
* Note .... if they want to inject florescent leak dye into your system only ever do it once - it will eventually damage your system if used too many times.

Receiver / Dryer = $73 only available through Mazda
Full system Re Gas +/- $140

I would imagine that the later model 5s systems have not leaked, but the drier 'can' is no longer taking out the moisture in the system (thus increasing the temp). Thus when new gas is put in (removing the moisture) it gets colder. Changing the can at the same time is of course recommended.

Is your location in Sydney? ... I had the work done at Auto-Fix Auto Electricians, 44 Dunning Ave, Rosebery (NSW) 02 9662 7557. They were highly recommended by a friend in the Auto Industry.

..... mentioning me won't get you any discount or favorable treatment - But the guys are car buffs and very friendly.

P.S. I purchased the aftermarket compressor and fitted it myself, just had the guys do the re-gas.