rite you people probably know i am after facts and true not assumptions and bullox. anyhow i need to learn about airconditioning not to go in to this trade but to diagnose things and spot a moron with no clue. in my endevour to find correct information i did come across this guys youtube video. I recon all he says make sense and contains a ton of vital information even to people with no clue at all about aircon systems. He said all refigeration works on the same principle car ones fridges freezers and house aircon heatpumps. its a long video but well worth whatching also has greate entertainment value on top of learning what i think are true facts. https://www.youtube.com/watch?v=BFOAhE2BcVs
ryanm2,
Feb 20, 6:32pm
What was the question again?
daryl14,
Feb 20, 6:38pm
Yes its the exact same cycle. 1. Compress gas to get hot HP gas. 2. Condense gas to become cooled HP liquid. 3. Remove pressure from liquid to make it expand (boil) to give LP liquid/gas mix - evaporating liquid draws in heat from its surroundings (the refrigerating). 4. Return all expanded gas that has done work drawing in heat, back to suction side of compressor.
Simply run the compressor the other direction and you now have a heat pump. Not needed in a car as we have hot water in the engine.
Its really that simple.
intrade,
Feb 20, 7:13pm
re * 3 did you sleep with your manifold gagues?
daryl14,
Feb 21, 6:06am
What was the question again? Lol.
johotech,
Feb 21, 8:31am
Which is totally incorrect.
intrade,
Feb 21, 8:33am
so everyone whatched it?
it also has value when you will work on electric hibrid cars the same stuff he talks about apply to it and modern diagnostic must be done the way he tells to do in its basic foundation!.
Never ever! EVER! assume Anthing , assumption is what gets you killed! . That is a 100% true statment from this guy with a ton of other true and funny facts he talks about. even when you own a house aircondition you can learn how you could kill your self with it when you dont know what you are doing and you will know what you do if you whatched this video. You will also spot a moron that you employ to fix your aircon when you take all he tells in from this video its why i think anyone should whatch it if your ignorant and think you should not whatch it then you probably should even more so.
You wont be using a letherman to cut a electric wire once you have finished whatching that i would say. its the basic foundation you should build any trade on what he tells and no i am not talking about sleeping with your tools lol. he uses that to make you picture and more easy get what he means the storys he attaches to his reasons.
johotech,
Feb 21, 8:36am
Didn't watch it myself. I've installed and repaired thousands of heat pumps & commercial refrigeration units.
What is your question?
Or are you attempting to fight the great plight of the ignorant?
intrade,
Feb 21, 8:41am
how do you find a leak on a refrigerant system? explain exactly how you do it step by step? thank you.
johotech,
Feb 21, 8:54am
Wasn't that covered in your video? I'm sure there will be videos of how to do it on Youtube?
Basically, you use an electronic leak detector. They can detect leaks of a few grams of gas per year. Of course, there needs to be gas in the system to be able to detect the leaks.
intrade,
Feb 21, 9:11am
yes but how there is steps you must take it should not be hard to tell me what you do how do you even know you have a leak? what do you do get your tester out and start looking for a leek as first step ? what the first few steps you do as professional? I can write you a step by step instruction how to diagnose a no start problem on a old diesel step i just write you the first few steps i take. step 1 is i question the customer step 2 is i check if it has fuel in the tank and try to start it for 30 secounds maximum depending on what the customer tells me if he said he cranked it for ages then i dont go cranking it some more i then check if i even have fuel in the injector pump or if its dry and the filter is out of fuel. these are the first few steps i do and i would like you to do the same
johotech,
Feb 21, 9:32am
As you know, your "no start diesel" example could result in 30 steps before you even get close to determining what a likely problem might be.
You still haven't said what type of system you are talking about. Let's assume it's a car air cond.
1. ok - question the customer - did it stop suddenly of gradually getting worse. 2. connect gauges and check if any gas. If some gas, run engine and check that compressor is running and working (by gauges). 3. check gas level by sight glass and gauge readings. 4. if gas low, switch off and check for obvious leaks (oil/dust around joints etc). Leak test.
Get the idea? Might be different depending if the customer said it suddenly stopped working or gradually got worse.
One of the "myths" is that systems need "regassing" regularly. Systems are designed to be 100% leak proof. There may be some very gradual leaking from hoses or seals, but that is so low that is shouldn't affect performance over at least 5-10 years. These slow leaks may even be visible by oil/dust on connections, but they may only be leaking a few grams of gas per year, in a system holding 500-1000grams or more of refrigerant.
If the system is sufficiently low on gas that performance is noticeably affected, then there is a fault (leak) which should be repaired. Whether people want to pay to repair a leaking compressor shaft seal (for example), which may leak enough gas over 3-5 years to be detrimental, is a whole different story.
That's enough for today.
intrade,
Feb 21, 9:40am
yes re "12 i think you are a professional. can you answer me the question when should the reciver dryer be changed ? and is there a risk of problem when you never change it? this is not a trick question i just need a professional to answer this for me and you have written enough proof that i would say you are a professional.
johotech,
Feb 21, 9:45am
The drier only needs changing when the system has been repaired / regassed after a leak (particularly on the low pressure side). OR if the system has been taken apart because of other repairs (engine replacement or whatever), then re-gassed again - the drier should be changed.
It doesn't need to be changed at all, if the system has never had a problem. It isn't a maintenance replacement item like an oil filter or transmission filter.
intrade,
Feb 21, 9:46am
ok thank you for that information i will memmorise it as true
johotech,
Feb 21, 9:52am
I just edited above. Difficult to account for all situation in brief messages.
One of the most important requirements regarding refrigeration systems is to keep them clean and dry. No dust, moisture or even moist air should be allowed into the system. Evacuation for long periods - up to 24hrs or longer depending on the temperature - may be required after some problems are repaired, to remove moisture from the system. Any small amount remaining will be take care of by the drier.
intrade,
Feb 21, 9:52am
like i know now why i dont want to use other peoples tools! i never liked to use other peoples tools and this video made it clear why i dont want to use other peoples tools as i just dont like doing it it dont feel right its almost as you want to throw em away. when your not used to them. just like the guy said in the video.
intrade,
Feb 21, 10:06am
now here is the problem i have on my vw the aircon works and its cold for 15 to 30 secounds after that ist shuts off . the thing is the belt driving the compressor bounces madly when the compressor is on, And i have been scratching my head for a while thinking it be the tensioner or the clutch on the alternator, but i dont think it is and that means i dont know but i think and i know the last guy changed the clutch and he told me they did not replace the dual mass flywheel, i think the faulty dualmass flywheel is what makes the compressor bounce as there is some slight bounce even with the ac clutch phiscicaly unplugged it comes and goes just like a faulty flywheel acts up wehn it was not changed with the clutch. or do you have a explenation why the belt would bouce wilently when ac is on? the compressor i can turn with my hand its not seezing up as that was what i was thinking could have been out of gas but then why would it cool for 15 secounds dont make sense to cool with no gas
intrade,
Feb 21, 10:11am
so basically i did not want to take it to some so called professinal who messes with my ac system charges me tousends and its still doing the same thing when the problem is my dual mass flywheel. so i need to learn my self how to diagnose ac systems i dont want to fix em but need to pebably have to buy some gagues and hoses that i am comffortable using and learn how to read the gagues correctly to rule a possible cause out in diagnosing as that is what i want to do professional diagnostic . not a moron whom assumes things .
mechnificent,
Feb 21, 11:10am
Intrade. The best material for learning and training is what they call "technical training manuals". All the manufacturers have them and it's what they train their technicians with. They explain the principles, the operation, and how all the various combinations of components work together in the different models. If you read the toyota ones you will find they use the same systems, and even design of components as all the other manufacturers. They will teach you far more and far better than any youtube guide will.
The toyota ones are online. If you can't find them I will look up a link for you, but I'll have to restart my computer in windows to do it.
mechnificent,
Feb 21, 11:18am
They have all the systems of the car, engine, aircon, trans, abs, electrical, and even hybrid technology.
This the real information. It;s the sort of information you need.
mechnificent,
Feb 21, 11:24am
Look in "links:, there are more training manuals.
mechnificent,
Feb 21, 11:25am
Nissan have the same service somewhere.
johotech,
Feb 21, 11:25am
It could be running for 15-30 seconds and getting cold, then shutting off on a low pressure switch, if it is low on gas. Possibly around 50-75% of gas remaining could do that. Only way to check is with the low side pressure gauge connected. If it runs again the same after a minute or so, that is probably the cause.
As for the vibrations, not sure which pulley you are referring to as the dual mass flywheel? The pulley on the compressor shouldn't be a problem, unless it has gone out of balance somehow. The compressor's are internally balanced without assistance of the pulley, as they never lock onto the pulley (with the clutch) in the same location.
Belt "bouncing madly", sounds like it could be loose?
If it's your crank flywheel you are referring to, then I guess you need to get that tested somehow. I'm not an expert in the mechanics dept. Do they have a rubber section between the centre and the pulley outside? Maybe that has deteriorated?
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