HVAC RMS

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HVAC RMS

Postby Technician » Fri Aug 25, 2017 8:55 pm

Any experienced members on here regarding Refrigerant Management Stations?

We have two RMS by two different manufacturers, a SUN QTECH III - Pro and a ICE Refrigerant Management Station, identical to a ECOTECHNICS LND10-TRK-1200 ICE.

The recovery process from either RMS does not seem to recover any oil when recovering R134a. It is possible that there is no oil to recover, on some vehicles, however an Audi A4 I recovered R134a from recently did not recover any oil but after dismantling the AC system I poured oil from the components, e.g compressor, condenser etc. It puts doubt in my mind about if or how much oil I should be putting back in the system not really knowing if oil is already in there!

Any thoughts?
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Re: HVAC RMS

Postby STC » Fri Aug 25, 2017 9:24 pm

With regard to adding oil to an AC system the one and only right way is to pull it apart, wash it out (flush it) then add the correct amount. Period !!!

These machines will not suck it out, vacuum will not boil it off. Anything you do other than the above will always be a compromise.

At the prices being advertised for AC service nowadays I suspect it can not be done properly to F Gas Standards without the certainty of losing money.
Then we have Halfords selling cans of R134 WTF!! Garages are using them offering a full AC Service.

Subsequently the consequence of excessive oil is a ruined compressor that is an easy Cop Out - We have recharged it and concluded you need a compressor - Slim chance, but a chance it rolled n with a serviceable compressor before the "recommended" refill of Oil Hydro7ucked it ???

Incidentally, I don't offer an AC service but I claim to have a knowledge of how it works and what it is..
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Re: HVAC RMS

Postby Liteace » Fri Aug 25, 2017 10:16 pm

STC wrote:With regard to adding oil to an AC system the one and only right way is to pull it apart, wash it out (flush it) then add the correct amount. Period !!!

These machines will not suck it out, vacuum will not boil it off. Anything you do other than the above will always be a compromise.

At the prices being advertised for AC service nowadays I suspect it can not be done properly to F Gas Standards without the certainty of losing money.
Then we have Halfords selling cans of R134 WTF!! Garages are using them offering a full AC Service.

Subsequently the consequence of excessive oil is a ruined compressor that is an easy Cop Out - We have recharged it and concluded you need a compressor - Slim chance, but a chance it rolled n with a serviceable compressor before the "recommended" refill of Oil Hydro7ucked it ???

Incidentally, I don't offer an AC service but I claim to have a knowledge of how it works and what it is..


The A\C machine will only pull any oil out thats, how can I put it, floating / mixed with the gas, most of the oil should be in the comp as thats the only part that needs oil, so if it only pulls very little out then there's only very little floating /mixed, most if not all A\C comps have a oil drain plug, if your lucky a very few have oil fill plug, so suck out gas, remove drain plug from comp, (most comps have to be removed as access to (fill) and drain) plugs are a pain in the ar5e) drain, re-fill (with the correct oil and amount), re-fit, re-gas, test
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Re: HVAC RMS

Postby STC » Fri Aug 25, 2017 10:37 pm

Full circle
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Re: HVAC RMS

Postby Technician » Sat Aug 26, 2017 5:07 pm

The reason I thought I'd ask this is because I used to use a RMS when I worked at Vauxhall some 13 years ago and their RMS did recover oil which I used to measure in the RMS before adding new oil back into the system when refilling. Because of this I was unsure whether I was missing something on these newer RMS's but I'm still not 100% sure at the moment. I have not found anything in the manufacturer instruction booklets to date to advise me either.
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Re: HVAC RMS

Postby victor2k » Sat Aug 26, 2017 7:21 pm

Technician wrote:The reason I thought I'd ask this is because I used to use a RMS when I worked at Vauxhall some 13 years ago and their RMS did recover oil which I used to measure in the RMS before adding new oil back into the system when refilling. Because of this I was unsure whether I was missing something on these newer RMS's but I'm still not 100% sure at the moment. I have not found anything in the manufacturer instruction booklets to date to advise me either.

Hello,
You will not find anything about AC in the new repair manual,but if you will recover 0ml then you must add 10 ml at refill,if you will recover x ml then you need add x+10ml oil. You must see the specs of the OEM oil and compatibility with PAG/POE oils.
Sometime a wrong oil can damage the AC system,more than the missing oil :(
Also you need to check the wear of oil(colour,PH,...)to decide to flush the AC system (the compressor can't be flushed,only the pipes,condenser,evaporator).
For a replaced part you must add some oil(10-15 % for condenser,dryer or evaporator,5% for pipes).A new compressor have/must have a full quantity of oil so the system must be flushed before the replacement and the dryer must be replaced.
If you use HP port to recover then some oil can be taked out,if you use LP then the oil will remain in the AC system(if you don't know what oil is in your system this is the recovery )Also you must use a filter if you will refill hybrid systems(PAG oil is poison for hybrid compressors).
The RMS make us a service monkey ...we don't konw nothing,only we need banana(recovery/refill/take the money) but the AC don't work :cry:
Last edited by victor2k on Sun Aug 27, 2017 7:59 am, edited 1 time in total.
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Re: HVAC RMS

Postby STC » Sat Aug 26, 2017 8:49 pm

if you will recover 0ml then you must add 10 ml at refill

That would be fine if you can be certain of 2 things
1. The Vehicle Manufacturer filled it correctly in the Plant - Which some don't !!! Lots of horror stories there.
2. Assuming it left the factory properly nourished then any post manufacture meddlings have been conducted correctly ? - Impossible !!!

I reality that system may need 20ml oil added or 50ml taken out. Half these monkeys have no clue if the bottle has any oil in it or not. If it has then it is a best guess as to what to force in there.
In the old days we had a glass window for just half an idea - long time since I have seen that on a car.

So not that easy offering an Air Con service for the price of a not so good bottle of wine ???

A thousand times or more I have heard these Supermen tell customers that they vacuum the system to test for leaks - A major myth that needs to be trampled on.

The RMS make us a service monkey ...we don't know nothing, only we need banana(recovery/refill/take the money) but the AC don't work :cry:


That is funny - because it is true ? And are they all clever enough to look at pressure after the vacuum process to be sure that it has been vacuumed for enough time or the dryer is not reusable? I know some new ones are.

Why do they ask you for Car Details and / or how many Grams of Refrigerant should be added ? I'm not F Gas (easily could be) but I do, on occasion fill up the odd one on the sly :oops: I rely on the stabilised pressure readings - both sides and measured ambient temp. Just like the climate Control Module or the Pressure & Temp Sensors on a Manual System. Good enough for them, good enough for me :o

I can see why the independents and the fast fit chains use an RMS, the majority employ untrained / sub standard labour - Service Monkeys (to use your phrase) As far as I know ALL the Franchised Main Agents are issued with an RMS ?? Is that because they don't train them in the Chemistry, Physics, Biology of Refrigeration ??? or it is deemed they cannot grasp it?

The same could be said for scan tools - I had one today telling me P0089 (Bosch KTS - Bosch EDC ECM - FFS - Vauxhall Movano - 10 years old - horsebox GU 9) is a Fuel Over Temperature fault - What a load of nonsense. Possibly viable if it did not have a Fuel Temp Sensor, but it does and is visible in actual values - Dynamic & Plausible figures.

Air con, not my gig, but what a sneaky, cunning, amazing discovery. Such a vast change in Energy / Temperature in such a small amount of time and distance - Mind Blowing!

And then the proportionate heat gains and losses at the condenser and evaporator - Witchcraft :D !!
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Re: HVAC RMS

Postby victor2k » Sun Aug 27, 2017 8:59 am

STC wrote:In the old days we had a glass window for just half an idea - long time since I have seen that on a car.

That glass sight on the cars wasn't for oil checking ,but for complete filling with refrigerant(when the bublles dissapear then you have the full transition from gas to liquid before the expansion valve).
Also the flushing AC system isn't so easy,is not a cheap procedure and a time consuming.I made some of this so I'm not talking just after reading in the books...
And not only the independend garages suffer from a lack of knowledge...AC servicing isn't a business for a true man :wink:
Someone who was payed to train us was amused by the percentages (10-15 % for condenser,dryer or evaporator,5% for pipes from total oil quantity)-readed by me from an old Ford repair manual- and cut off my conversation:"here we not talk about Ford" not knowing that the principle of operation is the same....
You can't diagnose a system if you don't know how it work,sometime is hard to find the right information.
Regards.
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Re: HVAC RMS

Postby STC » Mon Aug 28, 2017 9:44 pm

You can't diagnose a system if you don't know how it work, sometime is hard to find the right information.
Regards.


From that; we can deduce that the RMS is the wrong tool ? at least by itself. I would not use one in automatic mode !!!
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Re: HVAC RMS

Postby Fat Freddy » Sat Sep 02, 2017 3:36 pm

Like the theory STC but in the real world you wouldn't last five seconds. In fact some of your text book ideas will destroy an AC system. It's the kiss of death. - period.
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