Austin Mini A/C Problem and general assistance needed
 

Hi,

I have just got around to removing the air conditioning from my donor
1275cc A-Series MG Metro. It has the same engine as the Mini and the
air conditioning is a "Unipart" (Austin's accessory supplier)
aftermaket unit so it is quite universal. It is about 20 years old and
the guy I bought the car from said it needed regassing as it doesn't
chill.

I'll say straight away that I'm no expert in A/C but I very carefully
removed the system and have it ready for installation except for a fly
in the ointment.

On the dash there is a screw on control unit with 2 rotary controls,
one for fan blower speed, the other for temperature (you hear it click
when it turns through the position of the current ambient
temperature). My first problem occured when I unscrewed this and
lifted it slightly from the dash - at that point I heard a really
faint hiss (for about 2 seconds). When I lifted the unit further I
noticed it had a small diameter pipe (probably copper, around 1/8"
section) which was crushed at the point where it goes into the rotary
control - unfortunately it has subsequently severed. The other end of
the pipe goes into the main centre console ac fan unit with no unions
anywhere and is about 4 foot long.

When I unscrewed the main rubber plumbing pipes from the engine to the
interior ac fan unit, there was no hissing at all so I assume there
was no gas present.

If you're still with me, I have the following questions based on this:

- Is it possible to fix the controller (it really has severed flush
with the temp control unit with not much to play with)?

- Can I get a universal replacement which would join onto the end of
the pipe?

- Is this pipe's system continuous with the main refrigerant system -
ie if I re-gas the system, will it leak out from this point or is it
indepandant and just for temperature control

- Can the a/c operate without the temperature control if I solder up
the pipe (ie. just continuous output)

- In general, what's involved in regassing the system afterwards (and
does anyone know of a service centre that they would recommend around
SW London)

Any help in these areas (or general advice) would be most appreciated,

Cheers,
E.

> faint hiss (for about 2 seconds). When I lifted the unit further I
> noticed it had a small diameter pipe (probably copper, around 1/8"
> section) which was crushed at the point where it goes into the rotary
> control - unfortunately it has subsequently severed. The other end of
> the pipe goes into the main centre console ac fan unit with no unions
> anywhere and is about 4 foot long.
>

Yup this is a capilary tube that is now bad

>
> If you're still with me, I have the following questions based on this:
>
> - Is it possible to fix the controller (it really has severed flush
> with the temp control unit with not much to play with)?

It may be able to sent out and repaired but you can not do it .The tube is
filled with gas but not freon it is a capilary thermostat and has to have a
set amount to be at a certain preasure at a certain temp.
>
> - Can I get a universal replacement which would join onto the end of
> the pipe?

Maybe ,I don't know


>
> - Is this pipe's system continuous with the main refrigerant system -
> ie if I re-gas the system, will it leak out from this point or is it
> indepandant and just for temperature control

Nope ,Nope and yes

>
> - Can the a/c operate without the temperature control if I solder up
> the pipe (ie. just continuous output)

No


>
> - In general, what's involved in regassing the system afterwards (and
> does anyone know of a service centre that they would recommend around
> SW London)

Can't help you there as wrong side of the pond .
Mike
Classic Auto Works

I've just noticed that the capilary tube can be pulled out from the
main fan unit (other end of rotart temp control unit) - it's like a
sealed probe. Now that I look at it, this assembly is basically a
fridge thermostat - long sealed capillary tube with a rotory control
at the end which switches the 2 electrical sensors based on
temperature recorded.

The rotary control unit says 110v 240v on it so I assume Unipart have
just found a cheap generic household fridge unit and put it in a fancy
palstic shroud.

If anyone knows anything about this unit (eg. what sort of refrigerant
to use, whether or not the cheap kits on ebay for not much money are
any good).

Generally, has anyone tried to regas?

E.

Hi.

This sounds like it's an aftermarket-type or dealer install system,
rather than a factory installed system.

That being the case, and the capillary tube info you reference in your
next post, I would do this:
1) Take the control with capillary tube pieces to an appliance parts
distributor for a matchup.
2) Look on www.iatn.net for a technician in London, or post on the
forums there. (if you cannot post, email me and I can post for you,
I'm a member)
3) As far as regassing: Dunno what the regulations are in jolly old
England about R-12 refrigerant, here in the US the stuff is no longer
available to the hobbyist trade, only to certified pro's. I would NOT
use the "drop-in replacements" for R-12, the only way I would
substitute would be to put R134A in, that will require a new or
overhauled compressor, all new orings/seals and a new receiver/dryer
or accumulator.

Feel free to email me for more info if you wish.

Regards

Jase

(B.) wrote in message . com>...
> Hi,
>
> I have just got around to removing the air conditioning from my donor
> 1275cc A-Series MG Metro. It has the same engine as the Mini and the
> air conditioning is a "Unipart" (Austin's accessory supplier)
> aftermaket unit so it is quite universal. It is about 20 years old and
> the guy I bought the car from said it needed regassing as it doesn't
> chill.
>
> I'll say straight away that I'm no expert in A/C but I very carefully
> removed the system and have it ready for installation except for a fly
> in the ointment.
>
> On the dash there is a screw on control unit with 2 rotary controls,
> one for fan blower speed, the other for temperature (you hear it click
> when it turns through the position of the current ambient
> temperature). My first problem occured when I unscrewed this and
> lifted it slightly from the dash - at that point I heard a really
> faint hiss (for about 2 seconds). When I lifted the unit further I
> noticed it had a small diameter pipe (probably copper, around 1/8"
> section) which was crushed at the point where it goes into the rotary
> control - unfortunately it has subsequently severed. The other end of
> the pipe goes into the main centre console ac fan unit with no unions
> anywhere and is about 4 foot long.
>
> When I unscrewed the main rubber plumbing pipes from the engine to the
> interior ac fan unit, there was no hissing at all so I assume there
> was no gas present.
>
> If you're still with me, I have the following questions based on this:
>
> - Is it possible to fix the controller (it really has severed flush
> with the temp control unit with not much to play with)?
>
> - Can I get a universal replacement which would join onto the end of
> the pipe?
>
> - Is this pipe's system continuous with the main refrigerant system -
> ie if I re-gas the system, will it leak out from this point or is it
> indepandant and just for temperature control
>
> - Can the a/c operate without the temperature control if I solder up
> the pipe (ie. just continuous output)
>
> - In general, what's involved in regassing the system afterwards (and
> does anyone know of a service centre that they would recommend around
> SW London)
>
> Any help in these areas (or general advice) would be most appreciated,
>
> Cheers,
> E.