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andychill
13-12-2009, 12:16 AM
I'm relatively new to the AC world and could do with some advice from a couple of the more seasoned industry pro's, if at all possible.

My experience to date is mainly from working on smaller refrigerated appliances such as fridges, icemakers etc. About 6 months ago I dipped into the split AC market though, and have found it quite profitable despite the UK recession.

The problem I have is getting a working knowledge of safely and effectively using OFN for brazing.

The small systems I've installed have been fine so far, but I'm very concious that brazing without OFN could trip me up sometime in the future and I'd like to get that uncertaincy sorted out before next summer comes along.

Can anyone please point me in the right direction as to what OFN rig I need to buy, where to buy it from (BOC?) and roughly how to use it?

Oh, and before I get flamed, I am qualified to handle refrigerants and I do know what I'm doing, its just that my training wasnt exactly what could be considered 'formal' and there are one or two gaps in my base knowledge - OFN being one of them.

Any advice or pointers would be welcome:-)

ICE/RUNNER
13-12-2009, 02:34 AM
You will need a 2 stage nitrogen regulator 0 psi to 600 psi available from BOC and most refrigeration wholesalers, I would go to the fridge wholesaler as their ones also come with a secondary pressure gauge and shut off valve to allow the 2 -3 psi pressures to be set and a braided testing hose.

You only need enough of a flow of OFN to displace the air from the pipe, too much OFN will not let the brazing material flow into the join so you get little pin hole leaks. I made up a purging nozzle from some 1/4 pipe with 6 inches of capillary brazed in to it,the other end of the 1/4 pipe has a 1/4 fitting that goes on to a gauge line. I tape off the ends of the pipe to be brazed and put a small hole in one end to allow the OFN to flow out and push the purging fitting in to the other end.

Nitrogen is used during brazing to prevent oxidation and build up of scale during brazing, this scale can quickly block TEV's and capillaries also if you have warranty issues and the manufacturer finds out you did not use OFN during brazing you can probably kiss the warranty good bye (most manufacturers insist you purge with OFN).

IMPORTANT - only ever use oxygen free nitrogen (OFN) or High purity nitrogen for purging. Normal nitrogen has oxygen in it so does not stop oxidation and scale build up.

sedgy
14-12-2009, 12:16 PM
hi Andychill, as the above says correctly so , but in the uk an individual cannot buy a bottle you have to get it through a commpany who has a contract with them . all the best

Clk320_Greg
14-12-2009, 04:35 PM
Where abouts are you andy?

andychill
14-12-2009, 10:25 PM
I'm grateful to you guys for the info. I'm fitting Daikin and Mitsi's mainly, so warranty could be an issue but I can blag as well as the rest;-)

Greg; I'm based in Essex. Travel around a bit but mainly around the county.

tony--1
14-12-2009, 10:44 PM
Dont touch it if you are not trained how to use it .Daikin and mitsi will be pleased that you can blag it . sry to be so harsh

ICE/RUNNER
14-12-2009, 11:05 PM
Don't even bother trying a warranty claim with manufactures if you haven't used OFN, they do inspect the returned compressors and have been known to cut out fittings to check if its a big claim.

Clk320_Greg
15-12-2009, 03:11 PM
I'm grateful to you guys for the info. I'm fitting Daikin and Mitsi's mainly, so warranty could be an issue but I can blag as well as the rest;-)

Greg; I'm based in Essex. Travel around a bit but mainly around the county.

You not to far from me then,

if you wanted to pop up for a day then i would gladly show you around my OFN gear and share what i know! Ive got all the tickets and badges for it but definately dont clain to know it all!

As your a newbie i dont think i can PM you or you can me, but if you leav some contact details on here then ill get in touch!

Ta,

Greg

tony--1
15-12-2009, 10:59 PM
You not to far from me then,

if you wanted to pop up for a day then i would gladly show you around my OFN gear and share what i know! Ive got all the tickets and badges for it but definately dont clain to know it all!

As your a newbie i dont think i can PM you or you can me, but if you leav some contact details on here then ill get in touch!

Ta,

Greg

thats very nice ov you

andychill
16-12-2009, 12:12 AM
Thanks for your offer, Tony. Not sure where you are actually based - your profile does not give anything away.. -but time restraints in the next few months probably aint going to allow me a big enough window to take you up on it.

My flat landlady's ex is apparently a newly retired fridge engineer and reckons he can school me on handling OFN in return for a few beers and the odd balti in his favourite curry house, which sounds like a deal!

I'd hate you guys to think I'm a mug...;-)

VRVIII
16-12-2009, 09:08 AM
I'm grateful to you guys for the info. I'm fitting Daikin and Mitsi's mainly, so warranty could be an issue but I can blag as well as the rest;-)

Greg; I'm based in Essex. Travel around a bit but mainly around the county.

Andy,

Why don't you just attend the daikin or mitsi split training courses? These should cover any questions you have and only usually take 1 day. They should also cover correct commissioning procedure/fault finding ect and will save you future hassles.

Clk320_Greg
16-12-2009, 12:22 PM
thats very nice ov you

It would be nothing comapred to some of the help ive been given from guys on this site!


Thanks for your offer, Tony. Not sure where you are actually based - your profile does not give anything away.. -but time restraints in the next few months probably aint going to allow me a big enough window to take you up on it.

My flat landlady's ex is apparently a newly retired fridge engineer and reckons he can school me on handling OFN in return for a few beers and the odd balti in his favourite curry house, which sounds like a deal!

I'd hate you guys to think I'm a mug...;-)

No worries, im in cambridge if its any good to you.


Andy,

Why don't you just attend the daikin or mitsi split training courses? These should cover any questions you have and only usually take 1 day. They should also cover correct commissioning procedure/fault finding ect and will save you future hassles.

I heard that they are cutting back on the material in these courses as they are getting tired of being used as a training center for beginers, apparently a lot of firms were sending guys on these courses to learn the basics rather then the product specific training!

taz24
18-12-2009, 06:23 PM
It would be nothing comapred to some of the help ive been given from guys on this site!



No worries, im in cambridge if its any good to you.



I heard that they are cutting back on the material in these courses as they are getting tired of being used as a training center for beginers, apparently a lot of firms were sending guys on these courses to learn the basics rather then the product specific training!


That is the idea of the training.
They are product specific but do cover basic training.

They will only honour warentee if they are correctly installed, if you do not know how to install them, you won't buy them and they can't sell them.
It is in their own intrest to make sure as many contractors are capable of installing their products.

Book yourself on a few courses next year, they are still being delivered.


On a seperate note and one that is more worrying is your claim to have a refrigerant handling qual but do not know about OFN.

That realy does scare me and in truth it is one of the reasons why I am glad 2079 has been introduced.

What type of refrigerant handling qualification did you achieve.

Cheers taz.

Clk320_Greg
18-12-2009, 06:39 PM
That is the idea of the training.
They are product specific but do cover basic training.

They will only honour warentee if they are correctly installed, if you do not know how to install them, you won't buy them and they can't sell them.
It is in their own intrest to make sure as many contractors are capable of installing their products.

Book yourself on a few courses next year, they are still being delivered.


On a seperate note and one that is more worrying is your claim to have a refrigerant handling qual but do not know about OFN.

That realy does scare me and in truth it is one of the reasons why I am glad 2079 has been introduced.

What type of refrigerant handling qualification did you achieve.

Cheers taz.


It does raise the question about do you Andy know about pressure testing for leaks on exsisting systems? Tripple evac? When working on a broken down fridge do you blow back to check the capiliry?

Also you talk about 'handeling' OFN, do you know about cylinder safety?

And of course the biggest question...... What do you blow your fridge coils out with if you dont have OFN? LOL

Seriously tho, sounds like you need to get your self on a few courses. Im far far from the most educated chap on here so im not judgeing you!

andychill
20-12-2009, 01:45 AM
That is the idea of the training.
They are product specific but do cover basic training.

They will only honour warentee if they are correctly installed, if you do not know how to install them, you won't buy them and they can't sell them.
It is in their own intrest to make sure as many contractors are capable of installing their products.

Book yourself on a few courses next year, they are still being delivered.


On a seperate note and one that is more worrying is your claim to have a refrigerant handling qual but do not know about OFN.

That realy does scare me and in truth it is one of the reasons why I am glad 2079 has been introduced.

What type of refrigerant handling qualification did you achieve.

Cheers taz.

Thanks for the advice about mfr courses, Taz;-) I'll have a chat with the Daikin and Mitsi reps next time they visit and will see what's on offer.

In answer to your comments; I dont 'claim' to have a RHQ. It was a long time ago when I first learned about it though and as I said earlier, I've not needed to use the knowledge or technology until now.

I get the impression that some of you are hoping to trip me up or catch me out as being some sort of clueless doughnut.....;-) How about winding in the ego's a little bit, and having a bit of respect for each other till we get better aquainted?

Right; 2079 is b*****s in my opinion. Cut out the bad language mate please

Most seem to be clinging on to a falacy that it will stop engineers who don't hold the 2079 certificate from operating in the (false) hope that those that do can raise their prices and/or protect revenue streams.

Wake up! the refrigeration industry is light years behind electric, gas and water- all of whom have been subjected to tight regulation with effectively zero enforcement from the so-called authorities, who many stupidly prey will devise protectionism for the refrigeration industry, all off the back of allegedly protecting the environment and preventing global warming;-)

Ask the NIC EIC / CORGI registered guys how they feel about splashing out thousands in training and legislative 'compulsory' registration, only to see the unregistered engineers still making good money without a challenge unless they kill or injure someone.

2079 is a tax to work. Your 'training course' money and 'certification' will swell the coffers of refrigerant companies such as Dupont (check out who OWNS Dupont) but won't change the industry or stop 'unregulated' engineers from making a living.

Snob value may increase for those stupid enough to do the latest courses and pay out more and more of their hard earned cash to faceless corporations, but those that can simply fix the appliances that customers need to be working will just carry on regardless;-)

taz24
20-12-2009, 03:03 AM
I get the impression that some of you are hoping to trip me up or catch me out as being some sort of clueless doughnut.....;-) How about winding in the ego's a little bit, and having a bit of respect for each other till we get better aquainted?



I don't think it is about tripping you up, but most of us have worked hard to learn what we know and we have met all
the legal requirements also. So when someone asks for advice but is not prepared to jump through the same hoops to
get legal, it does anoy me.






Wake up! the refrigeration industry is light years behind electric, gas and water- all of whom have been
subjected to tight regulation with effectively zero enforcement from the so-called authorities, who many
stupidly prey will devise protectionism for the refrigeration industry, all off the back of allegedly protecting
the environment and preventing global warming;-)




Maybe you are right. Maybe the 2079 is a tax but it is somthing that you will do if you want to work legaly.
Some people drive cars without licences or insurance, not all get caught but some do.

But if I have to obey the law and jump through the hoops that govenment set me, don't be supprised if I
wonder what the likes of you are upto, especialy when you ask for help and laugh at me for trying to do right.

taz.

andychill
20-12-2009, 06:33 PM
But if I have to obey the law and jump through the hoops that govenment set me, don't be supprised if I
wonder what the likes of you are upto, especialy when you ask for help and laugh at me for trying to do right.

Not laughing at you, Taz. This thread has gone from a genuine request for help - to which one or two of you replied with useful non-judgmental info for which i'm grateful - but quickly degenerated into a **** waving contest.

I dont accept that government or an agency approved by them will actually do anything if someone doesn't have a piece of paper saying that they are competent. Sure they would if something went wrong, but as long as everything is OK, they#ll keep their noses in the trough of cash that you boys are providing them with.

Cynical? Yeah, sure. You know I'm right though.

As it happens, I value my business highly and will most likely get the 2079 ticket just before it becomes law so no one can point a finger or sully my reputation. No point being a skint maverick, but they will only get my cash right at the last minute and I'll make a point of getting it back two-fold at a later date (VAT or IR will pay it for me)

Surely you guys know in your hearts that you're being mugged with all this ridiculous legislation, don't you?

I have yet to meet a refrigeration engineer who seriously believes that refrigerants contribute to global warming or add to the ficticious hole in the ozone layer.

taz24
20-12-2009, 11:36 PM
Not laughing at you, Taz. This thread has gone from a genuine request for help - to which one or two of you replied with useful non-judgmental info for which i'm grateful - but quickly degenerated into a **** waving contest.



Do know somthing? In truth I honestly do not know if we are responsible, I honestly don't!!
but if we are responsible, even if it is just a small amount then surely doing somthing about it,
again even a small amount will make the earth a better place for our kids.

Thats how I see it. It might be naive but I do belive it.







I dont accept that government or an agency approved by them will actually do anything if someone doesn't have a piece of paper saying that they are competent. Sure they would if something went wrong, but as long as everything is OK, they#ll keep their noses in the trough of cash that you boys are providing them with.



Now I will admit I also work as a trainer and I have never hid that fact, so you might
think I have a vested intrest in it??

I try to be honest and open and do not pretend to know all the answers.









Cynical? Yeah, sure. You know I'm right though.



And I thought I was cynical :p




As it happens, I value my business highly and will most likely get the 2079 ticket just before it becomes law so no one can point a finger or sully my reputation. No point being a skint maverick, but they will only get my cash right at the last minute and I'll make a point of getting it back two-fold at a later date (VAT or IR will pay it for me)


Some how I can't see you ever being out of business :D :p






Surely you guys know in your hearts that you're being mugged with all this ridiculous legislation, don't you?

I have yet to meet a refrigeration engineer who seriously believes that refrigerants contribute to global warming or add to the ficticious hole in the ozone layer.


You probably would never belive any evidence that proved the effect of ozone depletion
or global warming and I'm not going to try to convert you.

Again in truth lets hope you are right. Because if all the experts are right we a doomed anyway :eek:

So all the best and have a great Christmas.

Cheers taz.

.

andychill
21-12-2009, 10:00 AM
Fair play to you, Taz. Nice post;-)

Brian_UK
29-12-2009, 11:34 PM
Just a bit of topic info that I came across this evening.

OFN flow for brazing recommended by Toshiba.

Flow Rate 0.05 cu.m/hr
or
Pressure of 0.02 MPa, 0.2 bar, 2.9 psig

Greengrocer
04-01-2010, 06:24 PM
I wouldn't plan on leaving it too late to get your 2079. Currently there are estimated to be some 20,000 plus persons needing this training by the 2011 deadline. Currently the largest training provider can only train approx. 1,200 persons a year if they work flat out. There are other providers but in total they can only cater for a fraction of those who need the training in the available time.
The upshot of all this is that most people will not be able to get on a training course by the 2011 deadline because there is simply not enough training capacity available. No 2079 by 2011 means you cannot work on any F-Gas regulated system.

Re. OFN safety (part of 2079 quals). A year or so ago a guy put too much pressure into a system from an unregulated OFN bottle and blew the top off a hermetic compressor. He was bending over it at the time & it took his head clean off! There have been numerous other accidents with OFN and gauges (many reported on this site on other threads) so be vary careful. Get trained sooner rather than later.

croc1774
09-01-2010, 12:40 AM
then i guess 2079 will be delayed, who no's.

andychill
20-01-2010, 11:08 PM
I wouldn't plan on leaving it too late to get your 2079. Currently there are estimated to be some 20,000 plus persons needing this training by the 2011 deadline. Currently the largest training provider can only train approx. 1,200 persons a year if they work flat out. There are other providers but in total they can only cater for a fraction of those who need the training in the available time.
The upshot of all this is that most people will not be able to get on a training course by the 2011 deadline because there is simply not enough training capacity available. No 2079 by 2011 means you cannot work on any F-Gas regulated system.

Re. OFN safety (part of 2079 quals). A year or so ago a guy put too much pressure into a system from an unregulated OFN bottle and blew the top off a hermetic compressor. He was bending over it at the time & it took his head clean off! There have been numerous other accidents with OFN and gauges (many reported on this site on other threads) so be vary careful. Get trained sooner rather than later.

That has to a candidate for Hilarious Post Of The Year, Greengrocer!

I'm assuming you either own or run a training centre that offers Fgas or 2079 courses and you need to put out scary stories to create some interest...:rolleyes:

If training places are going to be scarce, the deadline will just be extended. We all know that.

The bit about the hermetic pot taking someones head off is pure comedy genius:D Absolutely brilliant;)

Turns out the big scary OFN bottle is in fact just a pussy.

A bottle of Argon mix runs at around the same pressure, so its no big deal handling OFN.

Keep up with the Pravda comedy though. Still pissing my pants, mate:p

lowcool
21-01-2010, 12:19 AM
The bit about the hermetic pot taking someones head off is pure comedy genius:D Absolutely brilliant;)

Turns out the big scary OFN bottle is in fact just a pussy.

andy your a 100%:p idiot.prove it to yourself pressurise a pot at bottle pressure:) add some flame too if you want

andychill
21-01-2010, 02:33 PM
Lowcool, you Mook! Are you really suggesting that the lid of a 2.0mm steel pot is going to rip off, in one lump, despite the welded seam - due to over pressure from an OFN bottle?

What about the copper coils or the weaker pipework?

What about the connecting hose, or the guage coils?

Not sure why I bother trying to converse with people who seem happiest scaremongering in between blowing smoke up each others *******......repeat...leave out the bad language please

I see you're a VIP poster too: does that stand for Vacuous, Imbecilic *****?

croc1774
21-01-2010, 02:37 PM
lol think its time for admin to remove this subject before world war 3 kicks off.:D

Clk320_Greg
21-01-2010, 06:12 PM
Lowcool, you Mook! Are you really suggesting that the lid of a 2.0mm steel pot is going to rip off, in one lump, despite the welded seam - due to over pressure from an OFN bottle?

What about the copper coils or the weaker pipework?

What about the connecting hose, or the guage coils?

Not sure why I bother trying to converse with people who seem happiest scaremongering in between blowing smoke up each others ******......

I see you're a VIP poster too: does that stand for Vacuous, Imbecilic ****?


:rolleyes: Do a quick search and you soon see the guys you are talking to have some serious knolege in this area! Not really the best way to encourage them to help you is it?

glenn1340
21-01-2010, 07:39 PM
hi Andychill, as the above says correctly so , but in the uk an individual cannot buy a bottle you have to get it through a commpany who has a contract with them . all the best

Hand over the money to the Climate center and they`ll give you a cylinder. There`s a £80 odd deposit plus £28 refill charge. I didn`t go via my company as it was for private work and I think my boss might not be to pleased if he found out