R410 Flaring

[daddymac]

Has anyone had any issues on R410 split units with the flares failing. I used to solder on pre-cast flares for R410 systems, but this is becoming a bind! I'm thinking of going back to using my trusty flare block!
What does everyone else do?

Daddymac

[taz24]

I always braze the joints where posible but you have no option but to flare on the unit end. On the smaller units they are not too bad but I have know some of the larger ones be problematic. It does just come down to he quality of the flare. I know the newer flare blocks that were designed for the 410 system eliminates the problem to some extent. I have had expeirience with the high pressure euro fitting and I have not know one of them leak if fitted correctly.

Cheers taz.

[daddymac]

Thanks Taz!

Can you eleborate on the High Pressure Euro Fitting you describe...
Lockring Pete... is there a lockring precast flare in your range?

Daddymac

[monkey spanners]

I've had no problems using the new style ite flareing tool, except that on 1/4" pipe it tends to make oval flares where the offset cone first makes contact with the pipe At the last RAC show armacell had some brass flare fittings that you compressed onto the pipe with a gadget and it was said that the pipe would burst before they leaked, no glue/lokprep needed. You can see them in the armacell advert on page 114 of the climate center air con catalogue, but i don't think they sell them
Has anyone tried them?

Cheers Jon

[quiksilva]

Another vote here for the ITE equipment as its pretty much foolproof, I personally feel more flares fail due to overtightening - a pair of 15" wrenches on a 1/2" flare nut are no substitute for proper torque spanners

[taz24]

Thanks Taz!

Can you eleborate on the High Pressure Euro Fitting you describe...
Lockring Pete... is there a lockring precast flare in your range?

Daddymac

Monkey spanner did it for me

Cheers taz.

[Andy AC]

I've been using the eccentric cone type flaring tool that SRW have been selling for about £50. I got mine about 8 years ago - best tool I ever bought. I think it is also smaller than the equivalent ITE model, which is handy for the tighter spaces.

If you do use a torque wrench be careful on 1/4 tube as mine often doesn't click when it should on the lower torque settings. I've wound the flare straight off the tube a few times.

Andy

[davej]

im with Andy, we use a similar tool and we have had no problems at all, being careful not o overtighten when flaring is also important then the extra bit of give in the pipe can be taken up when tightening with your spanners. but not overtightening with the spanners. we also always smear some fine oil around the back of the copper flare so the nut does not grab and twist the pipe when tightening.

[taz24]

we also always smear some fine oil around the back of the copper flare so the nut does not grab and twist the pipe when tightening.

I agree with that. Oil on the flare will save you a lot of grief.

Cheers taz.

[Slim R410a]

we also always smear some fine oil around the back of the copper flare so the nut does not grab and twist the pipe when tightening.

I agree with that. Oil on the flare will save you a lot of grief.

Cheers taz.

What type of oil do you use and I've also heard of using oil on the inside of the flare or have I got the wrong end of the stick?

[taz24]

What type of oil do you use and I've also heard of using oil on the inside of the flare or have I got the wrong end of the stick?

I would try to use the same but I work on so much kit with different gases and oils that I would be carrying cans of the stuff. I carry an oil can with shell SD in (mineral) and only put a drop on the inside collar of the flare only. I don't carry opened synthetic oils because they are so hygroscopic.

Cheers taz.

[Dan]

Gentlemen, I see a need to simply avoid flaring tools after reading this thread. If there is not a tool better than this for a mechanical fitting, I think brazing the connections should be mandatory. I am a fridge guy, but we have been through the process of abandoning flare joints for the last 10 years.

It sounds to me, your advantage as A/C people is that you can reliably seal refrigerant joints with soldered connections. I am not ready to take on Home Depot all by myself, but I am not at all shy about casting EPA doubt on systems that rely upon mechanical connections that can loosen and leak. And be installed by marginally equipped contractors.

If I am off topic, my apologies.

[davej]

Yep im with taz24, or if pushed i use vac pump oil to smaer the back of the copper flare , between the copper and the brass flarenut collar.
Fundamentally dan is right i quess, we ought to just braze i know we do on the fridge side. But in all honesty if the flare is done correctly it shouldnt leak , should it?

[Dan]

Davej, I agree that a good flare shouldn't leak. Being in the fridge business, I used to see more than 500 flare joints connected to a common refrigerant receiver that held as much as 2000 lbs of refrigerant. From that standpoint, I am sure you can understand that flares are anathema in supermarkets in today's world. On the other hand, a simple A/C unit with only one or two flares has much less risk associated with it.

However, if I developed actuarial statistical tables to insure equipment with flared joints, I have enough experience to charge more regarding refrigerant loss and compressor malfunctions.

[taz24]

I agree with the other posts about flares being OK if done correctly.
I think recent problems could be to do with the new gases we use. I have read somewhere that upto 80% of all R134a ever produced has been lost.
The HCFC and HFC range of refigerants are harder to contain due to their smaller molecular size.

Cheers taz.

[Franzfernando]

it shouldn't really matter what type of oil you rub onto either side of the flare end.also when flaring you should not tighten 100%,this allows for the flared pipe to sit onto male connection and the compression allied with the oil to make a good seal.proper deburring of the pipe is of course mandatory before any of this takes place.

[daddymac]

The HCFC and HFC range of refigerants are harder to contain due to their smaller molecular size.

Cheers taz.

Thanks for the input guys... I'm not sure whether this should be a new thread... but given that HFC's are of such a small molecular size as Taz quite rightly says, then nitrogen is only good for a strength test, not a leak test (it's molecules are bigger). What's the best practice for leak tesing... Helium?? ...or am I being silly now?

DaddyM

[taz24]

What's the best practice for leak tesing... Helium?? ...or am I being silly now?

DaddyM

It's a problem is'nt it and the truth is, if I am to be honest, I do not know the answer But Helium may be the a way to go or at least a partial percentage pressure of helium and no I dont think it is silly.
The only snag with helium I can see is
You must ensure that the thing is bolted to the wall or it may just float of

Cheers taz.

[Electrocoolman]

Another vote here for the ITE equipment as its pretty much foolproof, I personally feel more flares fail due to overtightening - a pair of 15" wrenches on a 1/2" flare nut are no substitute for proper torque spanners

I totally agree...the ITE eccentric flaring tool is brilliant....torque wrenches should always be used....try reading the installation book before the job!

[frank]

We covered this some time ago http://www.refrigeration-engineer.co...orque+wrenches