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View Full Version : solder V Flare Driers



Latte
05-12-2003, 07:10 PM
I know its an ago old question, which sort of drier to use.
In the blue corner the Flared type, easy and quick to remove & fit a new one but can be prone to leaks.
In the red corner the solder type, pain in the arse to remove & refit, more leak tight but requires element to be open to atmophere longer before sealed & poss is solder getting in the system.

My question is this:- Obviously there my be a saturation point of a drier & if you have to take time to solder in a new one surely this increases the time it can collect moisture & will take longer to vac out properly.

I know all NEW units now have to come with Solder connections but has anyone looked into the time it takes to solder in a new one ect !!!!!!.

For the record, personaly i prefer the flare type fittings especailly if they have the Long flare nuts put on them, i don't normally find they lead because they are supported better.

Any Views

Raymond

chemi-cool
05-12-2003, 10:17 PM
hi Raymond,
like you, I prefer the nut type from the same reasons. but more then that, some manufacturers put them in such difficult to get to places and you burn other things you dont mean to and so on.
while with nuts, you only need two wrenches, three minuts and you are done!!

chemi

chemi-cool
05-12-2003, 10:21 PM
hi Raymond,
an open dryer, will not absorb moisture if it left open for a minut or so which is the time needed to replace.

chemi

Brian_UK
05-12-2003, 11:24 PM
Ray, I go with your liking for flare fittings, a smear of leak-lok on the joint faces will ensure it stays leak-tight.

Remember that you should be purging with nitrogen when brazing so the amount of moisture within the pipes etc. should be minimised.

Andy
05-12-2003, 11:34 PM
Hi:)
I personally think flare driers are a thing of the past, with the HCFC type refrigerant you are only lookng for a leak if you fit a flare drier. Me I locktight all flare driers whilst fitting, this way matter what happens they won't leak:D
Locktight is easy enough to break when a new drier is required and most driers are not changed, or even designed to changed on even say an annual bases. You should ofcourse change the drier everytime the system is broken into and minimise the times that the system is broken into. But if the system is not broken into once in every 5 years is often enough to change the drier.
As for solder driers, would not the heating of the drier remove any moisture added whilst the drier has been left open:confused:
I have oven heated driers in the past when stuck and re-used them again without any problems.
Kind Regards. Andy.:)

Dan
06-12-2003, 12:50 AM
I think it is important to qualify the application when discussing flared connections versus soldered connections for any component. It would be foolish to install 30 flare filter driers on all the evaporators connected to a parallel rack, for example, but I have seen it done. Supermarkets have all learned to use sweat TEV's simply because of the leak potential flares have.

On small equpment such as self-contained equipment, I think if the torches are already out that there is no significant labor time to install a sweat drier compared to a flare drier, and I see little opportunity for moisture intrusion.

As Andy points out, a flare connection can be made more reliable with leaktight. I would simply add that they would be even more reliable with a dollop of stay-brite.:)

Bones
08-12-2003, 12:12 PM
i prefer the flared driers, and have not had a leak yet on any they i have installed... but have found a few leaks on driers others have installed. mainly due to poor flares etc...

if i have to open a system up to work on it and it had a soldered drier, i would put a new on in and same if it was flared type.

just dont get to carried away with that leak lock crud :p guys around town here must use a whole bottle on new systems that they install.

Peter_1
08-12-2003, 01:52 PM
Hitachi prohibits use of leak lock on the joint faces of the flared connections.
I disagree that you can stop a leack - due to a bad flare - by using leack lock.
The only occasion where my apprentices may use leak-lock is on the threat itself of a flared connection. This only to prevent that water enters in the treat, freezes up and let burst the nut after a while.
A good made flare, firmly tightened must normal always be leak free due to the copper which is squeezed around the male flare while tightening the nut. If you squeeze leak-lock to the copper flare joint, then the copper can not squeeze completely around the male flare.
If there is a leak around the flares, then remove the bad one and make another one or use STEK couplings as obliged by the Dutch STEK regulations.
This is a compromise solution between flared and soldered connections.

Reeferjon
08-12-2003, 08:15 PM
Flare all the way, except when the fittings have rusted to the drier as in transport systems.
We have a choice really its one of 'O' rings or flare, the rings seem to be working well these days, but can be difficult finding a replacement if its been pinched.

chemi-cool
08-12-2003, 09:07 PM
hi
again, flare is good connection and leak proof if done correctly.(the flare, not the leak).
to make a good flare you need a good flaring tool like ridged with excentic cone. you will have to make sure that the flare is not too low as by tightening the nut you will cause the leak. too high flare will turn the tube and "squeeze" it. a dubble flare is great but takes time and extra tools.
I belive the best way is A. know how B.right tool C.a few drops of mineral oil.

chemi

Latte
08-12-2003, 10:17 PM
Hi all,
i was always taught to put oil on the flares to make them seal.
The transport (MTK) guys will know a bit better about this but on compressor shaft seals there was always great debate whether to lube them or not. i always found they sealled better with oil ON them as opposed to dry as the oil helped to act as a sealant as opposed to to dry joints going together. These days i use either oil or locktite whichever one is nearer.

Andy
08-12-2003, 10:32 PM
Hi:)
my point was that if you use a flare on HFC refrigerants, and you shouln't they require that little extra to seal them (even when they are perfect) me I lock tight them, it is easier to explain than a loss of £1000's of refrigerant a week after I have worked at the plant (even if the leak test was ok at the time).
Our duty of care to the enviroment is to minimise the loss of refrigerant, this is what I try to carryout myself and instill into others.
Kind Regards. Andy:confused:

Bones
09-12-2003, 10:38 AM
but i wonder how many people ensure to keep the system clean by purring nitro through while brazing... even on new systems. your 1000 quid of gas could be worthless, but at least it would still be recoverable... unless they didn't pressure test their system anyway to check for leaks and was already recovered into the blue bottle.

i think it is danfoss that has come up with this replacable flare for their driers/burn out driers etc... i was fairly drunk at a trade night when i seen this, so my memory is fairly vague or my mind playing tricks! lol... but i'm sure someone else will know what i'm talking about or seen it firsthand.

u buy flare's just the 45' flared copper bit and each time u replace a drier you replace the copper flare ring, i dont remember exactly 'how' the process worked (ie how it connected on) but it looked like a good idea..

And will give apprentices like me a little more work to do in making these things out of scrap copper just to save 5 dollars lol

Peter_1
09-12-2003, 08:25 PM
Thats the STEK coupling I was talking abouth, obliged in the Netherlands.

Bones
10-12-2003, 05:40 AM
ok well it has a name lol... and i must not have been dreaming hehe... looked like a good idea, am yet to use one but think i might be a fan when they become more available here.

Peter_1
23-12-2003, 03:52 PM
http://www.carly-sa.fr/english/desc-prod/krcy.htm

Frig Pig
23-12-2003, 05:58 PM
Well those seem expensive!. Nothing beats sweating on a dryer unless there was a burnout and you must go back to change your dryers a few times. In that case nothing is better than Nylog. Most liquid line are fairly loose so if i see a flare on one of my systems and it's open for any reason i'll cut off the flares and sweat a new one in. A tight system is always better than a convenient system.

Peter_1
23-12-2003, 08:20 PM
Originally posted by Frig Pig
Well those seem expensive!. Nothing beats sweating on a dryer unless there was a burnout and you must go back to change your dryers a few times. In that case nothing is better than Nylog.

You can do that perhaps in Canada but is forbidden by law in some countries and they have their reasons.

chemi-cool
23-12-2003, 09:36 PM
Hey Peter.

These Carly connectors are great but I use them only with new jobs. Never leaks!

It would be nice if they was a little cheaper.

Maybe someone from Carly is reading the forum nd wish to comment?

Chemi

Peter_1
23-12-2003, 10:22 PM
Originally posted by chemi-cool

These Carly connectors are great but I use them only with new jobs. Never leaks!
It would be nice if they was a little cheaper.
Maybe someone from Carly is reading the forum nd wish to comment?


Indeed, we also uses them in new installations and i agree again, they are expensive.
We call them STEK couplings according to the Netherlands refrigeration organisation name.

Bones
24-12-2003, 07:14 AM
<img src="http://www.carly-sa.fr/english/desc-prod/krcy.jpg" alt="this is the thingy i seen... see i was not dreaming!">

thats a picture of them! again i was not dreaming drinking all that free beer.... mmmmmm beer.... brb!

lovies were showing them off at the trade show in town a few months back. however i'm unsure if they are available yet... but as i said above i think i'll be a fan.

Peter_1
24-12-2003, 10:37 AM
Originally posted by Bones
<img src="http://www.carly-sa.fr/english/desc-prod/krcy.jpg" alt="this is the thingy i seen... see i was not dreaming!">

thats a picture of them! again i was not dreaming drinking all that free beer.... mmmmmm beer.... brb!

lovies were showing them off at the trade show in town a few months back. however i'm unsure if they are available yet... but as i said above i think i'll be a fan.

Bones,

We use these STEK connectors allready 4 years.

Bones
26-12-2003, 03:24 PM
Bones,

We use these STEK connectors allready 4 years.


there only new product here lol... gotta love the gueani pigs hey peter :P

Peter_1
26-12-2003, 03:34 PM
Originally posted by Bones
there only new product here lol... gotta love the gueani pigs hey peter :P

We had perhaps sooner the STEK connectors but we don't have free beer over here. :D
And hot temperatures for the moment;)

DaBit
29-12-2003, 10:00 AM
Now what is the problem brazing in a dryer? Heat the joint, pull one leg of the old dryer loose, heat the other, pull it loose, and the old filter is off. Stick the pipes into a new filter, apply heat, and let the braze stick do it's work.

Sounds as just as much work as flaring the pipe, applying the sealant which so many ppl use, applying the filter, and tightening the nuts.

Bones
29-12-2003, 11:59 AM
and have carbon crud go through and screw up the tx valve or block capillory?

basically as was said above, if you need to change a drier and their was a soldered on in place i would replace it with a soldered type. would just mean a little more consideration for the system whilst installing the new one like purr some nitro through, but you are not always lucky enough to have had the installer impliment some isolation to make it practicable.

and same for flared type... if your flares are good and oiled up you shouldn't need to add that icky leaklocker contaiminant.

personaly i use flared driers on almost all coolrooms we build at work... and 80% of callouts would be units containing a flared drier among other fittings.

PS. peter its all about the free beer man...

Peter_1
29-12-2003, 05:50 PM
And if there are oil residuals nearby and you heat too long with your flame torch, the whole thing sets in fire.

Peter

DaBit
29-12-2003, 08:03 PM
I noticed that too, but a piece of aluminium sheet does wonders.

Dan
29-12-2003, 09:21 PM
The most reliable refrigerator I have ever seen is the one in my home. It has no flares The least reliable refrigerators I see are commercial ones with flares. It seems the manufacturer is admitting flaws and letting the repairs happen easily.

The commercial refrigerators with fewer flares are the more reliable. The ones more likely to require repair are the ones with the greater amount of flare joints.

The fewer mechanical connections there are, the less likely the opportunity for leakage.

The ideal piping system is a single tube reluctantly interrupted by a compressor... and that interruption had better not be a flare joint.

angryk
31-12-2003, 01:43 AM
I remember hearing somewhere not to unsweat a drier. The reason being that the heat will make the drier give up whatever moisture it had absorbed during it's life. That being said, the new drier and a vacuum will take care of that. Anyway, I prefer sweating in driers as well.

bernard
20-03-2004, 11:05 PM
if replacing flared drier remake flares as old copper will be to hard plus smear with oil. if brazing, purge with ofn to reduce internal oxidization a new drier is cheap an old drier can be costly and reck a reputation.

Latte
22-03-2004, 06:47 PM
Hi Guys,
Well you made a convert out of me. I now if possible cut out flare driers & fit sweat wherever possible, In fact i probably have as many sweat as flare driers on my van now. So far i havn't had a comeback with one leaking as yet but i know my soldering isn't as good as it should be.

regards

Raymond

frank
23-03-2004, 09:29 PM
Just bought a torque wrench set by one of the leading manufacturers and I'm amazed at how little you have to tighten the flare nut to achieve a good seal. Looks like I'm guilty of overtightening in the past.

Must admit though that I'm a big fan of leaklock and still use it on every joint. Due to the advice given by lots of manufacturers, it certainly helps to reduce the amount of gas leakage form the new gas systems (size of the molecules etc.). Rarely get a leak now.

bernard
23-03-2004, 10:06 PM
I was once terrible for applying to much pressure when making a flare until I did a 410a course. The reason I believe a lot of people get leaks is for that reason they spread the copper and make it hard,whereas if you hold back on the pressure the copper is still soft apply a little oil around the flare and then when you tighten the flare nut up it molds and seals.I don,t have any trouble with leaks.However I have heard that some of the european countries are moving away from flared fitting all together.

bernard
21-05-2004, 09:46 PM
Hi:)
I personally think flare driers are a thing of the past, with the HCFC type refrigerant you are only lookng for a leak if you fit a flare drier. Me I locktight all flare driers whilst fitting, this way matter what happens they won't leak:D
Locktight is easy enough to break when a new drier is required and most driers are not changed, or even designed to changed on even say an annual bases. You should ofcourse change the drier everytime the system is broken into and minimise the times that the system is broken into. But if the system is not broken into once in every 5 years is often enough to change the drier.
As for solder driers, would not the heating of the drier remove any moisture added whilst the drier has been left open:confused:
I have oven heated driers in the past when stuck and re-used them again without any problems.
Kind Regards. Andy.:)

Hi chemi

This is the one I meant

Abe
21-05-2004, 11:01 PM
Leaf Lok...............Locktight............Stek
I have not used any of these........but please tell me what these things are?

Latte
21-05-2004, 11:28 PM
Leak Lock available from NRS Pt No 689882 comes in a toothpaste type tube and is a paste that you put around the threads of joint. I have used this especially on reefer units which are subject to vibration and works very well.

Locktite (permabond) HRP 160121 is a Liquid sealant which does much the same job, Once again i have used this and works ok, does more or less the same job as oil does on a flare although it then sets the flare nuts in place.

One other thing someone once recomended although i have never tried it, when fitting a drier outside put a little mastic/silicone sealer in the outside of the flarenuts where the pipe goes through it to stop water trying to get in their.


Obviously there is the other option which i like best, Solder everything then there is no need for chemical sealants.

Regards

Raymond

Peter_1
22-05-2004, 07:44 AM
STEK Coupling: see post 16 of this thread.

Abe
22-05-2004, 11:22 AM
Thanks Rdowcra............very helpful, thanks
These days I only use sweat driers..............or what u call it.......solder ones !!!
Peter1............How do I find post 16 ???
No its not you..............its me..........Im thick!!!!

Latte
22-05-2004, 12:07 PM
Hi Aiyub,
Post Numbers are at the top right hand side of each post in the green section usually prefixed with a #. I think you're last post was #36 (I might be wong without looking)

regards

Raymond

bernard
22-05-2004, 06:22 PM
Hi Raymond I am having same trouble. I get down to post 10 where do I click to move on to post 11 ect.It seems to have changed slightly

Thankyou bernard

chemi-cool
22-05-2004, 07:16 PM
hi bernard.

the "next page" botton is missing.

I'm sure when webram will get back he fix it.

meanwhill click the "back" and click on the page no. you wish to see.

chemi

Latte
22-05-2004, 07:49 PM
Hi Chemi'
Glad you come up with that as well, i couldn't see it but just thought it was me being thick !!!

Regards

Raymond

bernard
22-05-2004, 08:25 PM
Thankyou Chemi

Bernard

Abe
22-05-2004, 09:57 PM
It takes Clever Chem to fugure it out..........I thought I had a virus.........The next page, or all pages link is missing...
Also I keep getting User Name and password showing, top and bottom..........even when Im logged in
I have allowed cookies.........but I still have to enter my name each time and password
So when Peter1 said............look at post 16.........I went...........Duh????? :)

Peter_1
23-05-2004, 09:22 AM
http://www.refrigeration-engineer.com/forums/showthread.php?t=1392&page=2