I ask my previous installer, they do give warranty for the machine, but they don't warranty for existing pipe
Thanks, so far, Gain City and Coolserve has advised me that there will be no warranty from Toshiba if I reuse my old R22 pipes.
Called Toshiba service center to check, and the response was that their units should never be used with old R22 pipes.
Would be great if there was an official publication of their warranty terms. Don't know who to believe now.
Edit: Btw, GC staff advised me that only LG, Panasonic and Mitsubishi Starmex officially covers their warranty for reusing of old R22 piping.