AC DIY recharge

Hi Gang, maybe counter intuative of me but decided not to join BMW forums for time being while I get to know my new ride. So, a quick Q from a recently ex FL1 owner. Has anybody used the AC recharge in a can gizmo from halfords - does it work? Tx.

It worked well to top up a poorly performing system, but it didnt last long due to there being a tiny leak somewhere.

If your a/c is working but not as cold as you would like, they are worth a shot. If its non functional then they are pointless...you really need it leak tested and vacuum'd, the topped up properly.

Dunno about in UK, but over here now that summer is approaching, many fast-fit style garages offer an a/c system check and gas change for about 50€. Worth asking around, I would say.

my son i law used it and said it was ok ,but for just a bit more i can get a man round ,who will test the system before recharging it enough said i think.

Thanks chaps - good advice. As I don’t appear to have any cold air at all better get it checked over. TBH having working aircon has never worried me much (pipe split on my FL a couple of years back and never bothered to fix) but as this one has the climate control gizmo, I feel it needs to all work. Early doors fussing me thinks.

AC only stops working for 2 reasons. 1 part of the system has been damaged. 2 The system has been left on ECO mode for extended periods. This causes the oil to gather in the lowest part of the system. This is not good as the oil contains an additive that keeps the seals and hoses from drying out and leaking. Generally if the seals have dried out the whole system will need to be evacuated so the seals and pipes can be replaced!! If you are lucky the pump will be ok but sometimes the seals in that get damaged too with the obvious added cost

Nodge68 said:

AC only stops working for 2 reasons. 1 part of the system has been damaged. 2 The system has been left on ECO mode for extended periods. This causes the oil to gather in the lowest part of the system. This is not good as the oil contains an additive that keeps the seals and hoses from drying out and leaking. Generally if the seals have dried out the whole system will need to be evacuated so the seals and pipes can be replaced!! If you are lucky the pump will be ok but sometimes the seals in that get damaged too with the obvious added cost

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:behindsofa:

It's good practice to run the aircon for a few minutes every couple of weeks-even in Winter-for the reasons Nodge has explained.
Trouble is, people leave it turned off until the first hot day comes along....and in this day and age can be very rare !!

Regarding DIY kits. they are a rip off and there is always the chance of overfilling the system. There are quite a few places that will do a free check of the system and if they can't recharge it, you don't pay. Nothing worse than shelling out 30 odd quid for a small aerosol can, to find the contents pi**ing out into the atmosphere. Forget the claims about "With leak sealer added"-it don't work,

dito

I tried this a few years back spent about £35 on the gas, only to find it had all escaped thru a small pinhole in one of the pipes.
Spent another £100 replacing the pipe and also a recharge.

Kwik Fit (as an example) charge £29 for a re-charge as opposed to £35 for the Halfords can of gas

My local main dealer for Mazda, etc, did a full recharge and test for £49 on my TD4. Took almost an hour to do it! They also did a check on the tyres, lights,etc, all ok. Seemed to be good value for £49.

The cost of a tin of stuff int far oft the £50 you pay yer local tyre fitter to redo the air con. Difference is tyre fitter will have a machine which looks like r2d2 on wheels. It will de-gas, then clean, then re-charge yer system. Somewhere under the bonnet it will tell the type of stuff and how much to put in r2d2 when he does his magic on your air con. If there's a leak they will tell you.

Is it really £35 for one of those cans!!!! you can buy r134 a for £10 per kilo

Robbin bastards

If you suspect a leak it is illegal to charge refrigerant into a system, it needs recovering, pressure testing and re charging properly

Get someone that knows what there doing to look at it, if theres no refrigerant in there you have a leak and there no point recharging, if there is thre a component gone you would just be wasting gas by overcharging it and it will end up costing you more in the long run

The Ac refill cans are £34 for the first one, you get £10 back on the empty so the next refill can costs £24, you also need the adapter ( apx £15), this is a pressure gauge that screws on to the can (can be re-used), it has a the hose attached, the end of which clips on to the fill nipple on the larger of the 2 ac pipes. Through normal use all ac systems deplete, (apx 6 to 8% per year) so at 3 ish years on at around 20% gas loss the cooling effect starts to drop off, once the gas level depletes enough the pressure sensor in the ac line stops the system (ac compressor) from working to avoid damage. I have 4 vehicles all with ac and these top ups are spot on (as long as there are no leaks/damage) for £24 I can keep all 4 at peak cooling every year as opposed to to paying one of the many local service centers between £40-£50 per vehicle for the same privilege

Irishrover said:

:behindsofa:

It's good practice to run the aircon for a few minutes every couple of weeks-even in Winter-for the reasons Nodge has explained.
Trouble is, people leave it turned off until the first hot day comes along....and in this day and age can be very rare !!

Regarding DIY kits. they are a rip off and there is always the chance of overfilling the system. There are quite a few places that will do a free check of the system and if they can't recharge it, you don't pay. Nothing worse than shelling out 30 odd quid for a small aerosol can, to find the contents pi**ing out into the atmosphere. Forget the claims about "With leak sealer added"-it don't work,

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the aircon also helps demist in the cold winter months infact a lot of cars it comes on automaticly with the demist setting

beerbelly said:

the aircon also helps demist in the cold winter months infact a lot of cars it comes on automaticly with the demist setting

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The Freelander included

If u know ur system is holding charge and u can get a kit at good money then there ok. My passat I'm still running works great with it. It needing topping up so squirted a bit in and works brilliantly. But as said, if ur ac has suddey stopped working then there's a hole somewhere so would be useless using a kit like this.
Personally I wouldn't trust any kwik fit garage "servicing" my air con. I'd only use a qualified ac technician. I have one bloke I use in great Barr in north Birmingham and he's fantastic, cheap too.
He said to me its a good idea to pop ur ac on through out the year to keep things lubricated like nodge has said. The ammount of phone calls he gets on the first hot day of the year only to find they haven't used the ac at all over the winter.

johnsbwgood said:

If u know ur system is holding charge and u can get a kit at good money then there ok. My passat I'm still running works great with it. It needing topping up so squirted a bit in and works brilliantly. But as said, if ur ac has suddey stopped working then there's a hole somewhere so would be useless using a kit like this.
Personally I wouldn't trust any kwik fit garage "servicing" my air con. I'd only use a qualified ac technician. I have one bloke I use in great Barr in north Birmingham and he's fantastic, cheap too.
He said to me its a good idea to pop ur ac on through out the year to keep things lubricated like nodge has said. The ammount of phone calls he gets on the first hot day of the year only to find they haven't used the ac at all over the winter.

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Useful thread given time of year. Hammering down the motorway, hit the AC button and suddenly it started to work. Its not icy cold but it is defo better than nothing. No explanation and I will get it properly checked over when time and money allow.

If your fans are struggling to work/turn then you'll get some cool air with the air con on whilst at speed, as the air flow will help cool the rad, but it will stop when stationary if the fans don't turn electrically. If this happens then put air con on when stationary and give the fan a quick push (mind your fingers) and see if it starts to turn.

The gas in an Ac system also contains oil, this is lubrication for the compressor under normal operation, hence if the gas is low the oil/lubrication is low. All ac systems deplete with use, (average use maybe 6 to 8% per year) as the gas level drops the cooling effect drops off, once the gas level/pressure drops below a certain point (I believe about 17/18psi) a sensor in the system shuts it down, this is to protect the compressor, if it's low on gas then it's also low on lubrication. If the pressure in your system is borderline (just below the cut off limit) then it is possible that a sustained run at speed with the increase of hot air from the engine/radiator in the engine bay transfers heat to the pipework/condensor of the ac system, thermal expansion inside the sealed ac system can then increase the pressure and fool the ac pressure sensor into thinking things are ok and the compressor starts to run but because the gas is low the cooling is minimal, I suspect this is what happened to DD3. The point to remember is low gas = low oil you don't want to be running your compressor for long with low gas/oil levels if you do it wont survive for long

The oil sits In the compressor and is not in the refrigerant, not a lot of experience with car a/c but to say all a/c systems deplete with use is wrong under. If I even suspect a leak on a commercial refrigeration or a/c system the entire system has the refrigerant removed its re pressure tested and all the moisture is evacuated before the refrigerant is reinstalled

To say that every system just leaks overtime is completely against the f gas regulations, which govern the use of fluorinated gases

I'm not saying this isn't the norm on cars, but I can't believe that you can get away with accepting a leak, if I was caught knowingly venting refrigerant into the atmosphere it's a huge fine and possible prison sentence

Unlike commercial AC systems, auto applications do seem to loose pressure over time which as you say would contravene the regulations of use.
The problem with car systems is due to the design of the various couplings used and the way the system is used not to mention the harsh operating environment they have to cope with. The couplings that are used are often single bolted flange with an O ring seal, they are designed to be quick and easy disconnect when parts need replacing after an accident for example. The O rings need to be in contact with the preservative that is contained in the oil the system is lubricated with. This is where the user causes the issue by not using the AC for sometimes months on end, the oil containing the O ring preserver sinks to the lowest part of the system which causes O ring shrinkage and subsequent pressure loss.
If an auto AC system is used as the manufacturer states in the manual it should maintain it's pressure over a very long time but sadly they never are.