Help sought in stripping an old indoor aircon unit

[Corgigrouch]

The insurance would be null and void if the use of anything other than a refrigerant approved by the manufacturer or previously agreed by the insurer was to be used.... So at the moment it is R12 (Which has been banned by our friends in green) or R134a any other refrigerant would not be deemed acceptable not that anyone would know if you were to use R413a However by using R600 you are adding an unacceptable risk... A bit like other modifications that increase the insurers liability

Back to the OP... The fan can be stripped out and cleaned thoroughly without opening the refrigeration circuit.... They put the fan in at the factory after they made the evaporator....
Seems a lot of trouble for the money that it's worth though

 

[SimonH2]

The insurance would be null and void if the use of anything other than a refrigerant approved by the manufacturer or previously agreed by the insurer was to be used.

That one was put to bed many years ago - at the height of "any mod, no insurance, we're not paying out" 'scams'. Courts set a very firm precedent that for a mod to render the insurance null and void it had to be relevant - eg they couldn't refuse to pay out if you drove into something because they found modified lights on the back which were irrelevant to the crash.
And luckily for me, nothing I own is even remotely new enough to come under Euro type approval

I think we'll need to agree to disagree and leave it there.

Back to the OP... The fan can be stripped out and cleaned thoroughly without opening the refrigeration circuit.... They put the fan in at the factory after they made the evaporator....

Not on some of the units I'd seen - fan buried in the back and virtually inaccessible.

Seems a lot of trouble for the money that it's worth though

Depends. If all it needs is a bit of a clean but it's otherwise working, then why not just clean it.
I agree that it's probably not worth spending much on if it needs work.

 

[Corgigrouch]

Fair enough...

Well the damned fan got in there so it must come out! Sometimes you have to free the coils from the rear casing and prise forward slightly, undo the electronic controls to acess the fan motor and release that from the casing. then you slide the assembly out from one end..... If the job requires more than three hands then the unit gets scrapped.... Even if you do manage to clean it then it will always have that mouldy whiff until some bright spark sprays in a bit of air freshener and then the unit starts to smell of either cat pee or vomit.. There seems to be something in scents and perfumes that reacts badly in air conditioners

 

[Onetap]

That one was put to bed many years ago - at the height of "any mod, no insurance, we're not paying out" 'scams'. Courts set a very firm precedent that for a mod to render the insurance null and void it had to be relevant - eg they couldn't refuse to pay out if you drove into something because they found modified lights on the back which were irrelevant to the crash.

The insurance may be invalid if you managed to have a gas explosion in the car. SFAIK, it has never happened. You probably wouldn't be concerned about your insurance payout.

Propane is also the refrigerant of choice for DIY PC overclockers, there are some detailed guides on the internet, e.g.,
http://www.overclockers.com/build-your-own-phase-change-pc-cooling-system/

IMHO it's something that should be encouraged. We should encourage those who make an effort to educate themselves and increase their skills in any area and we should be wary of trade associations lobbying to impose restrictions under the health & safety flag-of-convenience, when the real purpose is to allow their members to earn piles of dosh from a simple and mundane trade.

 

[Corgigrouch]

Onetap, HC explosions in cars in the UK are currently unheard of because most folk have the good sense not to use them....

Here is the Aussie fellow proving how safe HCs are...http://www.youtube.com/watch?v=DjtowzVzl_4

Transporting flamable gasses in a container not suitable for safe transportation will void your insurance, an air conditioning system is not a suitable container

 

[SimonH2]

**** happens, so what's your point ?
It didn't explode*, it didn't even break the windows, no-one was seriously hurt - even the guy that was "right in it" (minor cut - head cuts tend to bleed very profusely and look much worse than they are for some reason). So in your own words, yes a good demonstration of how safe they actually are when compared with what Hollywood would have you believe.

From http://www.communities.gov.uk/documents/statistics/pdf/568234.pdf

Road vehicle fires totaled 32,500 in 2010-11
In 2010-11 there were 44 fatalities and 520 non-fatal casualties in road vehicle fires

So most likely something in excess of 30,000 fires not involving transporting stuff in unsuitable (your definition, not mine) containers. Pity it's not broken down any further.

* don't even go there, it was not an explosion, not even close. Don't worry, plenty of people are happy to describe fires as explosions so you're in good company.

Life is full of risks, get a sense of proportion.
[/quote]

 

[Corgigrouch]

Indeed, life is full of risks but there are some who are determined to increase the risks needlessly when suitable alternatives are available. A reasonable definition of an explosion is a rapid increase in volume and energy which is what I believe we saw... I'm sorry that you were disappointed that no windows were broken but if the vehicle was in motion I'm sure that the driver would have been suitably startled. I have no doubt that you would have calmly pulled over in a safe place and extinguished your hair before continuing your journey, miffed that your air conditioning didn't work.

I do find it a little worrying that you are happy to bodge your car rather than to carry out a good quality retrofit to your car, I'm sure that your attitude doesn't extend to your professional life

 

[Onetap]

Onetap, HC explosions in cars in the UK are currently unheard of because most folk have the good sense not to use them....

I disagree, it's more likely that most folk haven't got enough sense to know how to use them if they wanted to do so..

I have not said that there is no risk, I simply say that the risk is relatively small. The risk is small, compared to the tank of petrol & vapour, miniscule compared to the risks of allowing morons to drive, and small compared to the risks of using urethanes in car upholstery. The risk is manageable.

I was a little surprised that Bruce didn't open the windows and more surprised when he got his lighter out.

Transporting flamable gasses in a container not suitable for safe transportation will void your insurance, an air conditioning system is not a suitable container

So is a petrol tank safer? How about plastic lighters?

There was a US Army training film, Army Medicine in Vietnam, which made an impression on those who had saw it. This had the expected shrapnel and gunshot wounds, but the worst injuries were caused by petrol explosions; familiarity breeds contempt.

Regarding the abuse of 'safety' regulations, you need an F-gas ticket or safe refrigerant handling qualification to buy refrigerants, I believe. Fair enough. Some refrigerants have zero ozone depletion potential; do you require an F-gas ticket to buy these?

I don't know the answer, maybe someone does.

 

[Corgigrouch]

HC refrigerants require no F gas ticket but they do require a licence from the manufacturer... More conventional refrigerants all require an F gas ticket irrespective of their GWP or Ozone depletion potential... Having said that I believe that you can still walk into Halfords and buy an R134a death kit.

They are nicknamed "Death kits" because they kill compressors

A petrol tank or a lighter has passed minimum standards for their expected use... Generally plastic fuel tanks are used (I guess) because they melt and will not BLEVE.... Have you noticed that no fuel pipes are run inside the cabin of a car? There is a reason for that.... In fact I can think of no flammable liquids that are permitted inside the cabin of a vehicle so the occupant is moderately protected for a short time, time enough to establish a course for survival if one is available... Use of HC refrigerants shortens that time.

 

[SimonH2]

Generally plastic fuel tanks are used (I guess) because they melt and will not BLEVE....

You believe wrong. They are used because they can be manufactured more easily to complex shapes with less process steps. Making a metal tank requires multiple steps - pressing out the parts and assembling them. Making a plastic tank of arbitrary shape merely means making the roto mould for it and then production is just two steps - mould, trim.

Either will burst if the vents are faulty, ie both can create a BLEVE.

Incidentally, what you consider to be the explosion is not in fact an explosion. The explosion is the rapid pressure rise and release which can create a shockwave. The fireball that follows if the contents are flammable is just that - a fireball and not an explosion (the fuel/air mixture will be far to rich for rapid flame propagation). I have in fact witnessed one BLEVE, quite impressive though being water/steam there wasn't a followup fireball.

A reasonable definition of an explosion is a rapid increase in volume and energy which is what I believe we saw...

Wrong again, what you saw was rapid combustion, not detonation. Look up the definition : A violent expansion in which energy is transmitted outward as a shock wave.

I'm sorry that you were disappointed that no windows were broken but if the vehicle was in motion I'm sure that the driver would have been suitably startled. I have no doubt that you would have calmly pulled over in a safe place and extinguished your hair before continuing your journey, miffed that your air conditioning didn't work.

Au contrair, my first reaction wouldn't be to light a match Didn't you notice that the gas did not ignite before he lit the match ? In fact they were moving around taking readings and it didn't go up until he lit the match.

So, if mine went up (and I don't have a car with A/C at the moment anyway) I'd simply wind down the window (or crack the door*) and by the time I'd come to a controlled stop the gas would have dispersed below combustible levels. It wouldn't ignite, there's nothing inside the vehicle hot enough to do so - and yes, I do know how hot you need your sparks, poor ignition is a significant issue with LPG conversions.

Of much higher risk than the inferno - that didn't happen until the guy lit a match - is the "surprise factor" when the cabin fills with cloud which would happen with any refrigerant.

I do find it a little worrying that you are happy to bodge your car rather than to carry out a good quality retrofit to your car, I'm sure that your attitude doesn't extend to your professional life

Actually you admit yourself that propane is a recognised refrigerant. It has low environmental effects, is non toxic**, is readily available, and handled properly is quite safe. I realise you are scared of it - I'm not because I understand the concept of risk, and I understand that nothing in life is risk free and never will be in spite of what some numpties want.

But this is all completely irrelevant to the OP's question, I said ages ago that I'm happy to agree to disagree, but you seem to want to drag on with your emotional drivel (sorry, that's what it's turning into)

* Yes, it may surprise you to know that you can safely open a door while in motion - it's a lot quicker than opening a window.

** Though it does have other effects.

 

[Corgigrouch]

I believe that I have given the OP the answer to his question and he has happily cleaned the unit or is scratching his head over a pile of parts.... A job that is quite straight forward but tedious. His question was answered long ago.

It is a shame that you seem incapable of grasping the principals of refrigeration... You seem to believe that just because something is a refrigerant then it is suitable for any application, I feel that the overriding factor in your case is that propane is cheap.

The purpose of the Aussie test was to demonstrate the safety of the refrigerant in terms of non combustibility.... I suspect that he too calculated that he would have had a non combustible mixture, I guess too that his calculations were wrong and he was very surprised, just as surprised as anyone who may experience a failed evaporator, you may know what propane smells like but there are those who may not.... I have no doubt that you know what to do in the event of a propane leak but does every one else who drives the car? The manufacturers spend a small fortune on making cars as safe as possible and there are the likes of you who think that you know better. Not only that but you advocate the use on an open forum to people with very little technical knowledge but will follow your suggestion with dire consequences... As you have said Propane is perfectly safe when used correctly but you are not using it correctly. I am not known for my emotion and so fail to see where I am being emotional... It is common sense that the job should be done correctly but you are not capable of doing the job correctly as your knowledge of refrigeration seems limited to internet here say.

 

[SimonH2]

It is a shame that you seem incapable of grasping the principals of refrigeration.

Now how in the world do you come up with that idea ? I fully understand the principals - but I don't claim the practical experience you clearly have. Since we've been discussing the pro's and cons of different refrigerants and their compatibility in different applications, it's hard to imagine where on earth you come up with the notion that I know nothing at all about it.

You seem to believe that just because something is a refrigerant then it is suitable for any application

Sorry, complete bull manure. If you think that, then you clearly stopped reading anything I wrote many posts ago - when I first mentioned propane and you went into "chicken little" mode. It's something I see a lot, once someone sees something they don't like, they stop reading and comprehending what's been written and choose to see what they want to see - usually when they are looking for an excuse to be offended.

It is common sense that the job should be done correctly but you are not capable of doing the job correctly as your knowledge of refrigeration seems limited to internet here say.

Yes, it is common sense to do things properly, and that includes researching what replacements are available for obsolete (illegal*) refrigerants. That is something you should try some day - you give the appearance that you lack the ability to think outside the box - ie your trade body has said "to replace x use y" and you are incapable of seeing beyond that. Just because something is "on the internet" doesn't mean it's not acceptable information. Yes there's a lot of crap (you've added to that in this thread, sorry but it's true), the key thing is finding reliable information, and cross referencing against other sources. No that doesn't mean just looking it up on Wikipedia !
As an engineer, "the internet" is an incredible resource. I can remember when we used to have to subscribe to microfilm libraries of (back then where I worked) semiconductor data sheets. Now I can go directly to the manufacturer's website and get the latest data. What I don't do is work on the internet equivalent of "some bloke in the pub told me that ..." which is what you are trying to imply.

Now, unless you have something useful or positive to say, then I suggest STFU is the best course of action. "something positive" might be explaining why the car didn't go boom as soon as he let the refrigerant out - something you have said time and time again is the obvious consequence of using an HC refrigerant in an automotive A/C.

* As in banned for new installs and manufacture

 

[peekay53]

simon h you know your wrong about putting anything other than the right
coolant gas into your car "bomb" and you are just blustering and blowharding admit your wrong and stop acting like a 5 yr old "i dont have anything modern " you obviously have a computer iphone whatever but lots of us on here wish you did not worst thing in the world is a knowall especially one who knows less than he thinks keep googling cos i think thatis where you get your info.
rereading as you were responsible for air con unit where you worked surely you would have had your own filling tube and would not need to get one from friendly air con engineer


peekay53

we all make mistakes that is why they put rubbers on pencils

 

[peekay53]

would also be really interested you seem to be a man who likes to do the right thing so just wondering if you would be willing to inform your insurance company what you have regassed your a/c with and please post their comment for us all to see this would be the ultimate in proving you are correct in thinking it would have no effect on your insurance cover
look forward to your reply

peekay 53

we all make mistakes that is why they put rubbers on pencils

 

[Onetap]

HC refrigerants require no F gas ticket but they do require a licence from the manufacturer... More conventional refrigerants all require an F gas ticket irrespective of their GWP or Ozone depletion potential... Having said that I believe that you can still walk into Halfords and buy an R134a death kit.

Thanks for that, I didn't know the details and don't have time to look it up.

It is interesting that you'd need 'a licence from the manufacturer' to buy propane refrigerant, but not to buy a cylinder of propane for your barbecue. A severe case of jobs for the boys, I fear.

Indeed, life is full of risks but there are some who are determined to increase the risks needlessly when suitable alternatives are available.

Quite; so when the suitable alternatives have been intentionally made unavailable, people will use the riskier alternatives.