vibration and cracking tube

[Greek_engineer]

Hello my friends..Yesterday I encounter a strange problem.
I had to face an inverter outdoor unit that had to a specific point its tube(discharge,directly after leaving the compressor) cracked.
After fixing the leak,I noticed that the moment the inverter motor started, the copper discharge tube was highly vibrated for a period of 30 seconds and after that period the motor worked smoothly.
From my experience, I can understand that that was the reason of that cracking.I believe that leaving a tube to vibrate without restraining it can work better..what is your opinion?what would be the best solution so as to avoid further leaks in the future?
Many thanks..

[SeanB]

A loop or a flexible pipe section in there, space permitting.

[Magoo]

Possibly a discharge muffler will reduce pulse in discharge and harmonics that is cracking tube. May be a crankcase pressure regulator to reduce volume and velocity in discharge in start pull down mode.

[Greek_engineer]

thanks for your suggestions.I tried to fix that leak by putting extra copper glue directly up to the point of leaking.I hope not to have myself back so as to re-fix an another leak possibly by an other cracking.
the vibration is high the moment the compressor starts.However,I let it without putting an extra muffler and the like. I wonder why the design engineers didn't predict about that glitch during the construction stage..

[Rob White]

thanks for your suggestions.I tried to fix that leak by putting extra copper glue directly up to the point of leaking.I hope not to have myself back so as to re-fix an another leak possibly by an other cracking.
the vibration is high the moment the compressor starts.However,I let it without putting an extra muffler and the like. I wonder why the design engineers didn't predict about that glitch during the construction stage..

I think they would have if it was a design problem.
I dont think it is. I think you have a problem with
the way your compressor starts.

Somthing is wrong if it vibrates like that on starting.

It could be the compressor or the inverter but somthing
is causing it to judder.

It could even be something simple like the mounting rubbers
on the feet of the compressor, but what ever it is, if you
do not find the reason the discharge will break again.

You will end up repairing the pipe again if you do not find the
actual cause. Vibration eliminators, vibration loops will only
mask the fact that the compressor is not starting correctly.

Regards

Rob

.

[mikeref]

Seems like there might be a mechanical issue with the compressor when starting up with high suction, however you say the compressor runs normally after 30 seconds or so?
As the revolutions increase, suction pressure drops but head pressure rises. Thinking you may have a faulty discharge valve.

When the a/c has been running continuously for 10 minutes or so on cooling cycle, measure the inlet and outlet air temperature of the indoor unit with fan speed on medium.
Looking for 12 to 16 degrees C. (Taking into account gas type, ambient, and humidity.):)

[Watto]

Hi, is this system an LG model? There was a design fault where the discharge tube would crack on the bend out of the compressor; one way to repair this, is to replace the elbow with an actual elbow. Do not use tube bent with benders, it has to be an elbow welded in replacement.
cheers

[Greek_engineer]

As you can imagine the tube crackred again yesterday.
I think that the only possible way to fix it is either by changing the whole tube with a new one or calling the local distribution center just to refer them from what the problem had been caused.
The a/c is new and the customer os getting sad with them.