Cab air con performance

klaatu

klaatu

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Considering changing our 1999 A class Hymer for a very recent PVC. Driving back from a (French) dealer today having failed to get him to take the Hymer as part exchange ("trop vieux") with the air con turned on and the fan full blast, with the ambient temperature at 32C and full sun, I was baking. I'm hoping that the cab air con in a modern Fiat-based PVC will perform much better - is that a forlorn hope?
 
Peugeot boxer based coachbuilt, (65 plate) very warm here in Germany, had air con on on the way to Rothenburg this morning, was ice cold, had to keep turning it off?
 
last summer i cranked the air con in the cab right down, it got too cold. thats on a 12 plate fiat

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For best performance and longevity the A/C should be recharged every two years, as they change the oil at the same time.
 
ChrisL said:
For best performance and longevity the A/C should be recharged every two years, as they change the oil at the same time.
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It was given a "full service" when I bought it a year ago but I don't know if the aircon was done at that time.
 
If it isn't performing as well as you would expect find an A/C specialist, some are mobile and will come to you, as part of the recharge process it will be tested for leaks etc. So worthwhile. You may find that Kwikfit are the cheapest but they messed mine up so i wouldn't recommend using them.
 
Is cab AC good enough that, when it's still 30C at bed time, you can run the engine for 10 mins and cool off the whole van?... 'Coz it's bloody hot here at the moment and my USB powered fan isn't cutting it!
 
Guigsy said:
Is cab AC good enough that, when it's still 30C at bed time, you can run the engine for 10 mins and cool off the whole van?... 'Coz it's bloody hot here at the moment and my USB powered fan isn't cutting it!
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I did exactly that in my old rapido and it did cool it down to a comfortable level
I now have roof air con in my new van

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Guigsy said:
Is cab AC good enough that, when it's still 30C at bed time, you can run the engine for 10 mins and cool off the whole van?... 'Coz it's bloody hot here at the moment and my USB powered fan isn't cutting it!
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Neighbors will love you running the engine late in the evening. The aircon would hardly be working after 10 min, doesn't do much in hab area unless it's been running for a few hours. Also running diesel on tickover will give you very big repair bills.
 
Our 3-year old pvc has pretty good cab a/c. But because we spend a lot of time in Spain, I asked our local UK-based Fiat agent to give the a/c a full service at the same time the chassis was serviced a couple of weeks ago.

Since then, it's been freezing cold in Blighty, so haven't had a chance to test it anger and see if it's made it any colder. Although, as I said, it had been working perfectly fine in any case.

The a/c service inc re-gas and refresh cost £50 + vat

The parts used and included were:

Fiat 59137962 - Pollen System Cleaner
Fiat 46004671 - DFS Product
 
A lot of newer vehicles now have a different gas in them that is very expensive I have just bought the machine to do it it's called 1234yf gas and is fitted to a lot of vehicles after Jan 2017 well cars anyway not sure,about motorhomes must go check my 2018 MH never gave it a thought but my wife's 18 plate golf has this gas in it older models will have the 134a gas
We charge £59.95 For the 134a gas service and £159.95 for the new 1234yf gas service up to 500gramms 10p per Gramm after this
 
My 2016 Fiat PVC aircon didn't seem cold this spring. Had an aircon guy out, and he found the high pressure valve was leaking. It had lost most its gas in 2 years. He replaced the valve and it seems to be good now.
 
ChrisL said:
For best performance and longevity the A/C should be recharged every two years, as they change the oil at the same time.
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Not true.

Ive been servicing Automotive A/C for 35 plus years.

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TeeMyob said:
Not true.

Ive been servicing Automotive A/C for 35 plus years.
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Can you elaborate on that please, most vehicle manufactures say two years between A/C servicing and they definitley add new oil because i've watched them doing it. I'm sure they can go on much longer without servicing if they have to but will that give your system maximum longevity?
 
Came back from the south of France on Monday, temperature outside was around 32c. Couldn't leave the a/c on full it was too cold.
 
ChrisL said:
Can you elaborate on that please, most vehicle manufactures say two years between A/C servicing and they definitley add new oil because i've watched them doing it. I'm sure they can go on much longer without servicing if they have to but will that give your system maximum longevity?
Click to expand...

My opinion is that if its working, don't mess with it.
If you have an issue with it dont go to a garage with an automatic aircon machine as the mechanics are not aircon specialists. They may be OK for a regas/ service if the aircon has reduced performance over many years but for an issue on a system that has started within a couple of years of being new or regassed get a specialist out.
 
jezport said:
My opinion is that if its working, don't mess with it.
If you have an issue with it dont go to a garage with an automatic aircon machine as the mechanics are not aircon specialists. They may be OK for a regas/ service if the aircon has reduced performance over many years but for an issue on a system that has started within a couple of years of being new or regassed get a specialist out.
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Thank you for the clarification, I did say in post no 8 "If it isn't performing as well as you would expect find an A/C specialist".

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ChrisL said:
Thank you for the clarification, I did say in post no 8 "If it isn't performing as well as you would expect find an A/C specialist".
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A lot of the Groupon type offers depict an mechanic with aircon equipment leaning over a vehicle.
Its easy to come to the assumption that these people know what they are doing.
However its more likely they know how to use the automatic machine.

Just trying to make it clear that these types of regas are not the same as using someone who specializes in aircon.
 
Mikescuba said:
Came back from the south of France on Monday, temperature outside was around 32c. Couldn't leave the a/c on full it was too cold.
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Just turn the heat control up a bit. This is where ours has been for a couple of weeks.

15609346448021498953308.jpg
 
Had to put some gas in ours as we set off for Spain, good job it was a warm day or I wouldn't have known until we got there ?

It had just lost enough to stop working, fortunately I had some in the garage so I kept putting bits in until the condenser fan stayed on. Will have to sort it properly when we get back... If it needs sorting that is. Funny stuff 134a ?
 
In my experience, DO NOT go to a non-A/C specialist for a "re-gas". They have no knowledge of how A/C actually works, they just hook it up to a machine which sucks out one lot of coolant for another. Yes it's cheap, but if you want your A/C to work well for many years, go to a specialist. They will run a full test on your system, they put a special dye in to indicate any leaks and make sure that it is not only recharged but fully working to its maximum efficiency. I used the cheap option twice on my car....total waste of time. First time (Halfords) made virtually no difference, 2nd one (on an offer from Wowcher or Groupon...can't remember) drained the system, then said they were unable to do anything else as the machine couldn't put anything back in! Took it to a specialist, cost £150 and they basically took it apart, lubricated, checked, pressure tested, oiled, cleaned and recharged and the temp dropped like a stone!
 
klaatu said:
Considering changing our 1999 A class Hymer for a very recent PVC. Driving back from a (French) dealer today having failed to get him to take the Hymer as part exchange ("trop vieux") with the air con turned on and the fan full blast, with the ambient temperature at 32C and full sun, I was baking. I'm hoping that the cab air con in a modern Fiat-based PVC will perform much better - is that a forlorn hope?
Click to expand...

I'm sure the full sun on your A Class windscreen will always make the aircon try that bit harder! Huge greenhouse you're driving there. One of the (many) reasons I sold my Burstner Aviano was the discomfort from so much solar heating when driving on a fair day. My other vans, before and since, have been coachbuilt with Ducato bases and the aircon has been fine for the job. That said, one did blow an aircon pipe (near the front by the radiator) due to vibration (badly fitted...?) and that caused the gas to leak out. £150 ish if I recall. Chausson, in case you're wondering, but Ducato nevertheless.

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Thanks for all of the replies. As far as my Hymer goes, it's now somebody else's problem, as I agreed a part exchange deal today. I look forward to being icy cold next next month!
 
ChrisL said:
Can you elaborate on that please, most vehicle manufactures say two years between A/C servicing and they definitley add new oil because i've watched them doing it. I'm sure they can go on much longer without servicing if they have to but will that give your system maximum longevity?
Click to expand...

Sure.....

Refrigerant and oil contained with a correctly working and regularly operate automotive A/C System can last for many years. Without need for "topping up" or servicing.

So long as the system is used on a regular basis, even in Winter *, a good system, will perform without any great service requirements. That said, you may wish to use a deodoriser in the evaporator and make sure the condenser is kept clean/ A gentle hosing with detergent.

What can and usually does happen, especially in cooler climates. People only use the A/C during the summer. This is what often leads to issues the following summer. *See note above: In Winter, the LP or low pressure and or electronics within climate control systems, switch can prevent the compressor from running. So make sure you try and user the A/C on milder winters days.

At some point, the A/C system may lose its refrigerant or "Gas" as most term it.

This can be for many reasons, the last thing you want to leak is the evaporator. As on most vehicles. its an 4rse in thee world of a job. Can take many days and lead to a lot of pocket screws.

When and if you require the A/C recharging or "re-gassing". Its should be done properly and with care. We spend many days and a huge amount of time to get certified and allow us to legally work on Refrigeration systems. Only to be called by a garage to recharge a vehicle where they have replaced the cars engine cooling radiator. In order for them to do this, the condenser may have to be removed. Rather than pay for the refrigerant in the system to be safely recovered, the technicians often simply "blow it off".

If a leak or low gas is suspected:

Firstly, the amount of refrigerant in the cars system should be checked. Then appropriate action taken. That is, if its a small loss, it can simply be topped up. If there is no refrigerant in the system. The system should at least be Vacuum tested or better still, pressurised with OFN or Oxygen Free Nitrogen. Any leaks should be repaired or components replaced. Then, re leak tested and the system evacuated with a deep Vacuum Pump.


Back to your point regarding the oil.

When a vehicle is recharged with a specialist machine. The PAG oil can be measured and small amounts added automatically. The amount added is very small for cars or vans, Usually just a few ml. This is because, when the refrigerant circulates and constantly changes state from liquid - vapour. The refrigerant carries oil around the stem with it. When a leak occurs, tiny amounts of oil can escape with the gas.

Or, for example, when the condenser is changed, a more common failure. PAG oil is added to compensate for the loss. A standard sized condenser will only require 10-25 ml of oil adding.

Its is not common practice to change the oil. It is, usually with the odd exception simply topped up.

Again, if the compressor is changed, that itself will contain its own fresh oil.

It is very important that the system contains the correct amount of oil. Too little can cause the compressor to seize and that can turn in to a serpentine or ancillary belt failure. You do not want too much oil in either.

I am not sure where you have seen people change the oil, its rarely required and not and easy job. You cannot simply drain it or suck it out. The oil will be sat in the evaporator, condenser, compressor, expansion valve, receiver drier and the res of the hoses and lines. More likely a small top up.

I will add some photos of a top of a recent Toyota car. This was a larger than usual System with Three evaporators. One for front seat passengers, one for rear seat passengers in the roof and one in the cars toolbox/fridge. Even that with a 1.25Kg charge of R135a, only required 25ml of new oil adding in.

I hope this helps.

Added is a photo to show the amount of PAG oil for the Toyota (2x 12.5ml) and
A Photo of a perished condenser. It's not leaking, just falling apart and lost its efficiency.
The car has never been recharged in 20 years and we reclaimed the refrigerant and re-used it, back in the same vehicle.

We don't use a machine to carry out repairs by the way. Its all old School here.

TM
 
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Many thanks for the comprehensive reply, it's very informative. Re the topping up with oil they put about a cup full of sun pag 56 i think into the machine and most of it was gone when they finished, my car is a Mitsubishi with a dual a/c and took around 950 grams of r134a if my memory serves me well.

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