Aircon refill, I need advice

[Urbalizer]

On the Wiki it recommends a reill weight of 1kg for the refrigerant, but my dad has questioned this saying it sounds too much, in fcat he is adamant it is too much, so i said i would double check with you guys that it is correct.

[Gadgeroonie]

the story is to fit slightly less, so the system is not overpressurised

[The devil]

I had mine recharged earlier this year and it had 750 in it but I was advised to put 900 back in but there was talk of about 1100

[Urbalizer]

Thanks for the advice, i will let my dad know that i double checked and the weight is correct, i just know he is still going to carry on grumbling though, he just cant get his head round that his BMW only takes 550g.lol.

[JLSELAN]

FWIW, recommended fill for U.S. units is 600 grams--works perfectly!

[joust]

Use the sight glass. It's covered by a piece of sticky paper from the factory, but easily found.

If you have a decent AC company they will understand that. If they don't, then go to another....

J

[wessexrfc]

joust said:

Use the sight glass. It's covered by a piece of sticky paper from the factory, but easily found.

If you have a decent AC company they will understand that. If they don't, then go to another....

J

Be careful using the sight glass on a system so small as this (this is why it is taped over). Its part (the top) of the reciver drier and only indicates when liquid or part liquid vapour is leaving the receiver. Problem is, because you need to charge R134a in its liquid form (due to it being a blend) it is very easy to over charge if you only use the sight glass. Most systems have a tolerance of +/- 25-50 grams which is OK if you are charging on weight, but very easy to over or under charge if only going on the sight glass. I would recommend 700-750 grams, then finish on pressure and sweat-back, if needed

[joust]

I think you prove my point.

These guys (http://www.coolitautomotive.com/) told me when they were working out how to sort out mine that they really didn't need to actually know what the fill was as they could work it all out by first principles. They took me through how they would use a combination of recovery, pressure checking, slow filling, temperature measurement and using the sight glass to give a perfect fill for the optimum efficiency.

I don't actually follow the details of all what you posted (not sure what a sweat-back is!!!!) but I'm assuming that if an aircon place has to know what the charge is, they probably aren't experts???

J

[wessexrfc]

joust said:

I think you prove my point.

These guys (http://www.coolitautomotive.com/) told me when they were working out how to sort out mine that they really didn't need to actually know what the fill was as they could work it all out by first principles. They took me through how they would use a combination of recovery, pressure checking, slow filling, temperature measurement and using the sight glass to give a perfect fill for the optimum efficiency.

I don't actually follow the details of all what you posted (not sure what a sweat-back is!!!!) but I'm assuming that if an aircon place has to know what the charge is, they probably aren't experts???

J

J, I'm in agreement with you that if you have an A/C fault take it to a good automotive/refrigeration company. As far as the charge, if its not labeled, it can be difficult to know the factory charge/correct charge. Taking the old gas out won't tell you because chances are it will have lost a portion of the gas through use, (the gas, due to its small molecular size can leak through the flexible hoses and seals), pressure will help, but sweat-back or dew-point will indicate to the engineer that you have liquid gas evaporating across the evaporator correctly,(if your guys are doing air on air off temperature readings, then they are either super keen as you would need to get to the evaporator, in behind the dash or are measuring the air temp coming out of the vents, this reading would not be of much use due to most Nobles not being able to stop blowing hot air when dial is in the cool position). Using the sight glass can be a bit hit or miss due to the torrence of the gas charge being so small, but the advice coolitautomotive gave you was very good. Sounds like it worked for you!!

[Urbalizer]

No they only got their ICE STATION a couple of months ago, but they did have to go on a training course, they are still adamant 950g is too much because in their book it goes on cabin size apparantly, but they shrugged their shoulders and said if you want 950g then that is what we will fill it to, heard someone say they filled theirs to 1.1kg with no problem.
As somebody else said mine was working fine on 650g but after a year of use it was not running so cool, dunno might just play it safe on 750g.

[wessexrfc]

Get them to put in 750 grams, if you get condensation on one of the pipes going to the compressor, (the suction) after 5-10 mins your charge/system is going to work as well as it can. Note cabin space has no relevence to the charge.