Guidance on a/c pressures and temperatures ?

[aviper4u]

Looking to see what other members MX5's a/c systems are running in terms of pressures and vent temperatures.

My car is running around 30 pounds (25 degrees ambience) and 6 degress celcius at the vent on recycle.

Manual says these are acceptable ranges though still believe this is very weak.

Before I get online forum murdered I totally understand that the MX5 has a hot cabin (gearbox tunnel / soft top / etc) and a known poor a/c system though I am just looking to see what other people are running?

Thanks and have a good one

[hks_kansei]

I do really have to give credit to the Mazda engineers.
They somehow managed to create a car with such terrible ventilation that the only way to get any kind of decent ventilation happening is to remove the roof.


As for mine, pressure I have no idea, but I doubt mine is as cold as 6deg, it feels more like maybe 10degrees (granted, that's just my guess without using a thermometer)


In summer I drive with the roof on, windows up, set to recycle and fan at full.
I'd still prefer it be cooler though.

[KevGoat]

No idea about pressure or temperature at the vents in my NB, but if I put my hand at the vent, the air coming out feels pretty cold. Just that the fan is so weak, even on full setting there's insufficient air throw to get that cold air to you.

Air con probably wasn't one of their biggest priorities when engineering the car ...

A friend who bought a Mazda 3 last year was complaining to me that the air con in the 3 during last summer was pretty lack luster too. Took it back to the dealer three times and they told him it was all at spec.

Sent from my GT-I9100T using Tapatalk [url='http://tapatalk.com/m?id=10']now Free[/url]

[aviper4u]

A friend who bought a Mazda 3 last year was complaining to me that the air con in the 3 during last summer was pretty lack luster too. Took it back to the dealer three times and they told him it was all at spec.

hmm maybe small Mazda's have weak a/c as I got mine tested years ago plus injected with UV dye and no signs of leaks.............

checked the system pressure and temps this time around though curios to see what other people are getting with their cars?

i understand though if the average guy cant be stuffed putting thermometer on the vent lol cheers

[SlugRacer]

If your car is running R134a refrigerant @30psi that would equal an evaporator coil temp of about 0C and the general rule of thumb is a 6-10C temp difference across the coil so the 6C at your vent is ok. Try cleaning your condenser and you may lower your pressure which will lower the temperature.

[MrRevhead]

5.1C at the vent in the trusty old R12 system running on some modern Hychill HR12

That was about 4 weeks ago after the system just got evacuated and refilled.

FYI, some AC specs for reference:

NA R134a systems:

Refrigerant (R-134a) Capacity 21.2 oz
Blower inlet temperature: 86 - 95 F
Low Pressure side: 22-35 psi
High Pressure side: 200-227 psi
Static Pressure (engine off) 72-114 psi

NA R12 systems (pre 93/4)

Refrigerant (R-12) Capacity 28 oz.
System Operating Pressures
High Side ............... 171-235 psi (12.0-16.5 kg/cm  )
Low Side .................... 21-43 psi (1.5-3.0 kg/cm  )