Reusing copper piping

[Leon47]

Hi all i am new in this forum so bear with me if i am posting in the wrong section. I want some help regarding a new installation. Basically I have an 8 year old Mitsubishi 22,000 btu ac inverter that unfortunately its inverter board is fault and as you probably know is too expensive to buy as new. I took the board also for repair to an engineer but no luck. I am going to replace the ac with another brand. I am very concerned pls as piping is very difficult to change and was wondering if I can use same piping. Both units the old and the new are with R410A as a refrigerant. I am willing to change the piping if there is need but they are passed underneath a gypsum board and need to take some of the gypsum out but as I said I am willing to take the risk.

Any help and suggestions will be very appreciated. Thanks Gilbert

[Brian_UK]

As long as the quality of the pipe is suitable for R410a then you should be fine reusing it.

Make sure that the existing system is acid free.

If possible keep the lines charged with nitrogen and sealed when you have it disconnected from the unit.

[Grizzly]

Hi Leon.
There are many others here that know this side of our industry much better than me.

Historically I have retro fitted Fujitsu units which have facility to accommodate the reusing of existing pipes.
I cant remember if they did a R410a version?
I would imagine all the big boys do a version which is suitable for retro fitting?

Good luck.
Grizzly

[Leon47]

As long as the quality of the pipe is suitable for R410a then you should be fine reusing it.

Make sure that the existing system is acid free.

If possible keep the lines charged with nitrogen and sealed when you have it disconnected from the unit.
Thanks for your reply. I was very confused as I normally everyone says change pipes if you can or have any doubts but also say that if you are using same gas would not be a problem and pipe diameters also match as I checked. Mitsubishi will be replaced with an Airwell ac unit as Mitsubishi in my country are very expensive.

Thanks again for your time and help and have a good day

[Leon47]

Hi Leon.
There are many others here that know this side of our industry much better than me.

Historically I have retro fitted Fujitsu units which have facility to accommodate the reusing of existing pipes.
I cant remember if they did a R410a version?
I would imagine all the big boys do a version which is suitable for retro fitting?

Good luck.
Grizzly

Thanks for your reply you were very helpful. I have been installing ac unit for 15years but some doubt always arise along your way and it is good to have confirmation from an expert and also this will be installed in my home. Thanks again.

Good Day

[Greek_engineer]

changing the lines is an issue..it costs but you have piece of mind in case you have the compressor broken.
personally , I try to clean the old line, purging them with nitrogen.it removes oil and other dirts. some guys re use the old lines without having them cleaned...I do not know who is the right guy...

[chemi-cool]

There should be no problems with reusing the old pipes.
Follow the advice of the Greek engineer and it should just fine.

You might have to redo the flarings but that's not a problem.

[Leon47]

changing the lines is an issue..it costs but you have piece of mind in case you have the compressor broken.
personally , I try to clean the old line, purging them with nitrogen.it removes oil and other dirts. some guys re use the old lines without having them cleaned...I do not know who is the right guy...

So if I clean with Nitrogen should not be a problem. Thanks

[Greek_engineer]

In Greece many techs do not changr lines due to econimic crisis.the costumers do not care since they pay less.I have seen many installation without even cleaning the lines.nitrogen costs in Greece.
So,there is an amount of risk not having the lines properly cleaned.

[vikky1971]

Refrigeration and HVAC is all about cleanliness and precision. Follow Greek_engineer's advice.