- Thread starter owas
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R134a has dropped though this summer were back to half of last years prices. £265 for 12.5kgs vs a nudge over £500 last summer.
R134a is being made obsolete, and mfrs are now producing on quotas which created a shortage last year prices however are bumping back down its not massively unusual for gas to fluctuate tbh.
In the OPs case there are a multitude of things that need checking,
always start with the condenser fan give it spin.
then visually inspect for leaks pag oil stains so its easy to inspect, compressor seals and condenser are the usual suspects.
without manifold gauges the next tests cant be done, OFN, vacuum and make sure the systems tight refill with the correct weight of gas add oil.
Now this next part could be a cause of an issue, FORGET the pressure switch they will work or they wont a hammer doesn't fix them, IF its hitting High pressure most likely its a failed thermostat, what happens is the compressor will run and run and run lovely and cold for about 10 minutes then the core freezes and it stops. turn off leave for 20 minutes and everything will work fine. The compressor MUST cycle 2 minutes on 20 seconds off something like that if it doesn't then the stat needs replacing early electronic stats always gave issues.
High pressure faults will often cause leeks two other components that can give issue, filter dryer where a desiccant bags broken up in the system or an expansion valve, these again will cause HP.
owas
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The denso code did specifically point to the pressure switch,
Refrigerant dual pressure switch circuit fault -
Possible causes -
Refrigerant charge low
Refrigerant dual pressure switch circuit:
open circuit, high resistance or short circuit to B+ voltage
High engine temperature in high ambient temperature
Ever since I tapped it, it has worked perfectly and cleared the code
bar the one leak of course,it's still ice cold very quickly and was so driving the 2 hours today.If the system has been off for quite some time as you say with a leak on it then all the gas has leaked out and been replaced with moist air, the desiccant in the drier will be sodden, which means when you switch on it works for a while then the moisture freezes up at the expansion device, then you then have to wait for that to defrost, then it will work again and then stop and so on it goes.
owas
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That's not how it's working though so I'm confused,
From starting the car,
If I turn the AC on, the fans run and its freezing in approx just over a minute, then it just stays like that for alsong as I run the car.
If I need to replace any of the parts I won't bother and live without it again
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The denso code did specifically point to the pressure switch,
Refrigerant dual pressure switch circuit fault -
Possible causes -
Refrigerant charge low
Refrigerant dual pressure switch circuit:
open circuit, high resistance or short circuit to B+ voltage
High engine temperature in high ambient temperature
Ever since I tapped it, it has worked perfectly and cleared the code
All its telling you is the pressures hit its low or high side and isn't what it expects to be...… The switch is generic safety item that's been in place since year dot. Its to stop you either sizeing the compressor on a low charge or even worse black death, or blowing a pipe or a condenser to pieces on a high fault.
On a system with a leek it would only be a matter of hours or minutes before you hit the LP switch.
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That's not how it's working though so I'm confused,
From starting the car,
If I turn the AC on, the fans run and its freezing in approx just over a minute, then it just stays like that for alsong as I run the car.
If I need to replace any of the parts I won't bother and live without it again
So what's the issue???
owas
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Currently the one leak i attached.
But before that I had no idea how cold the AC should be, i confused the cold fan air for it, it wasn't working at all after having it charged, kwikfit shouldve known that the compressor wasn't engaged and the fans not running, but hey ho.
After tapping the switch (possibly just a bad wiring connection until I did so?) Its all started working as I now know it should be and I instantly got freezing air, has worked fine since, but I have to sort the leak.
I have no idea how long the AC hasn't been used, I did ask the PO who said there was a leak in the condenser, it was just the shot O ring though.
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A leek will last no time if unfixed as it is the system will need to be recovered then fixed , the proper method is to fill the system with nitrogen, hold fix and empty... technically its illegal to fill a system with refrigerant before testing.
Are you sure its still leaking??? a 750gm system is flat in under a week even with a small leek.
owas
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It held pressure when they tested it, I think the numbers are on the receipt I'll have to check.
I've cleaned the area up and nipped the bolt up slightly in the hope it decides to seal now
iIl check it again after using it tomorrow, otherwise I'll just take it back down there to discharge it and put a new o ring in.The system will not allow it to fill if it identifies a leak....Mine took 4 weeks to empty but empty it did...I'll look further into it in the morning, hopefully just a switch or a fuse
Was lovely when I drove back from getting it recharged at the 6c, they said there wasnt any leaks ... But the system hasn't been used for years which probably hasn't helped.
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It held pressure when they tested it, I think the numbers are on the receipt I'll have to check.
I've cleaned the area up and nipped the bolt up slightly in the hope it decides to seal now
Small leak though and these fancy charging stations don't detect, I'm old school have done bits and pieces for decades and always work with manifold gauges, these charging stations were invented so someone with virtually no experience can do the job, there not always correct.
I'm confused because standard practice should be to leek test to double working pressure (circa 150 psi) on both sides, you shouldn't drive away and then visibly see a leek it should have been more than covered before charging.
Even then 134a can leek, it has a very small Molecular size its one of the reasons along with the lower working pressures that it couldn't be put into an old R12 system as it simply finds it way through the hoses, and thus why R12 systems were more reliable.
Something else, standard O rings cant be used in modern A/C systems the specialist synthetic PAG oils dissolve them in a few months, its important to use the correct seals.
slim_boy_fat
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It helps with demisting etc, I leave mine running all year as it saves the seals drying out, with the attendant system leaks.
owas
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I didn't have the any o rings so I popped down to my landy garage who put one on out of a kit, I did say it was an AC line, looks like that will leak too then, fairly certain it was just a standard one
Not sure if I can get access to it without taking the radiator out again.
Not sure if I can get access to it without taking the radiator out again.
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I didn't have the any o rings so I popped down to my landy garage who put one on out of a kit, I did say it was an AC line, looks like that will leak too then, fairly certain it was just a standard one
Not sure if I can get access to it without taking the radiator out again.
Your soon know in a week or so if its still leaking there's little point in touching the system unless you lose all the gas, your have to split the fitting to repair. The problem with the L type metric fittings is they often need the correct type and thickness of O ring to seat, Sanden used to go as far as saying that you must check the p/n of the O ring as you can not visually tell, few are that much of an anorak (myself included) to start looking up P/N for O rings.
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TBH most systems never need touching if the A/C is ran and used, Iv got 7 off road pieces of equipment and 5 vehicles ageing between 0 and 15 years, Iv had to replace 1 compressor on 1 telehandler in 5 years and that was because the operator went creek paddling in salt water, which also seized the starter, alternator and took out all the wheal alignment sensors, Tomorrow iv got to look at a neighbours 1995 JD with 10,000snd hrs on it, So again I think that's well out of expected duty's on a system that hasn't ever been serviced.
I do very little A/C work these days because it is so reliable. I also woulndt expect operators to use equipment without.
owas
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Definitely leaking at that joint, I'll get the gas removed and change it.
Nothing else I can see is leaking, still ice cold for hours.
What I dont like is, the jagaur part list shows a few different o rings, with no mention to where they actually go
Looks like Halfords do a set so I'll just grab one and hope it's got the right size
Nothing else I can see is leaking, still ice cold for hours.
What I dont like is, the jagaur part list shows a few different o rings, with no mention to where they actually go
Looks like Halfords do a set so I'll just grab one and hope it's got the right size
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Other thing to check is the clamp for wear some allow the pipe to vibrare which ruins the register where the o ring sits. If you can wiggle any of the assembely signs are not great and your never get it to seal.
Will halfords recover and re use the gas then? Many places will charge a disposal fee to recover.
Will halfords recover and re use the gas then? Many places will charge a disposal fee to recover.
