Flared fittings

[t527ed]

Originally posted by kevink1955


Compression fittings where never intended to be used on any refrigeration or HVAC system.

i have some 20yr old lennox units that would disagree with that.

[tinknocker service tech]

a lot of other brands used compresion fitting to way back when and are still holding just fine. guess even the manufactuors were (HACKS) also back when

[curiousgirl]

boys i assure you i am a "inny rather than an outy" lol. WHY are some of you so paranoid on here about talking ac/heat? I been a lurker on this site for awhile cause we have rent houses and I like to learn as much as possible about everything that goes into them. I only know some ac lingo due to the fact we've had to replace enough of them over the years. Heres my limited knowledge...Air handler-its the deal in the closet. Condesor-the outside unit. Freon lines-the lines from the inside unit to outside unit. Duct work-its where the air goes thru. Vents-the ceiling deals. Disconnect-the box outside by the outside unit. And thats about it.

So why are some (not all) so paranoid about HO posts on here? I can see not specifically telling inexperienced HO's ways to fix things, but sharing general knowledge cant be bad for your trade can it?

[masterair]

The flair fittings are fine, What Brand of System is this? and is it a heat pump or straight A/C ?

[curiousgirl]

rheem ac and no heat pump, 10kw elec heat

[tinknocker service tech]

Ok all kidding asside. Flare connections have been arround for many years. They work well and as long as they are flared properly and not loosened up they will never leak.
Braze and solder connections are the industrie preferance as of late but it is not theonly applcation allowed. Even if the lines have to be removed for some reason the flare can be retightened and will hold as if it were new. Sanyo,Mitsu*****y, and some others still to this day only use flare fittings for the connections.
You have no need for concern and the flere fittings will be fine most likely for the life of the unit.
I personaly like flare connections be cause they are quicker and easyer to do. hope this puts your mind at ease
NOW WHERE IS THE PICTURE heheheheheheeh

[faith]

I attended a Vendor training session where this question came up. The “Factory” rep said that it seems nearly all major manufacturers of residential refrigeration equipment have (at one time or another) tried and abandon mechanical joints on the liquid and suction lines.

He himself had asked the design engineers why? They stated very clearly that the harmonic vibrations generated by the motor(s) will over time challenge the integrity of a mechanical joint. Given that the design life of equipment ranges between 10 to 15 years brazed joints which withstand vibration far better have won out for SOP.

(Personal Opinion) I've been questioned by automotive mechanics repeatedly on residential HVAC AC units. The answer I give is always the same, automotive AC's rely on an external pulley system for power, therefore are not subjected to the same level of vibration residential equipment is with an internal compressor motor. Same goes for using dye tracers, automotive compressors do not have to deal with cooling internal motor windings which are susceptible to the corrosive nature of the dye material. Seems that many automotive mechanics view residential AC from a different perspective. Typically upon a tactfully discussion enlightenment occurs on both sides… Unfortunately now and again a narrow viewpoint clouds the waters… I’ve personally observed that often those with the least knowledge hold the most rigid “opinions”.

In the end Charles Darwin may have had the right idea, time alone is the greatest winnower of aberrancy…

[junkhound]

"as long as they are flared properly and not loosened up they will never leak" Never? new one on me.

As in Faith's post, vibration will loosen joints. It is not that all will fail, but the failure rate for flares is much higher than brazed or even o-ring joints. Lots of flare systems can last for decades, but if there are 100,000 joints in similar systems, more flares will fail than brazed. Often stated here, it is the installation. "Flared properly" is harder to do than braze, double flare even more difficult. For instance,somewhat conversly, the failure rates of soldered electrical joints is higher than that for crimped connections made with proper tools - the reason is errors made in soldering are greater than the errors made crimping with aerospace tools.

As to residential HVAC flares: If one lives in a sesmic zone, the flare will likely leak after the next major earthquake, where the braze has a much better chance of surviving.

[rookie 19]

It shouldn't matter if its done right and not done by a hack

[tinknocker service tech]

gentalmen you are right. there is no absolute in this trade and never is a strong word to use in this case.
if flaired properly and not touched or any sizemic desturbance they should not leak. braze joints are much stronger and can with stand better. since the system is old and in a few years it will more then likely need to be replace worring about a flare connection that has held for years isnt nessasary unless it should start to leak. this is not likely to happen but can

[redhawk]

Freon lines...... that kills me....