High Efficiency HVAC Condensation Line in Abandoned Chimney

[David Triplo]

After some searching, I determined where my water issue was coming from in my ground unit in my 1890s, gut rehabbed 3 flat. In my 95% high efficiency HVAC system the PVC pipe connected to a copper pipe in my abandoned chimney on the 2nd floor was corroded where they met which leaked outside of the chimney causing damage to my carpet in the ground unit beyond the drywall. The chimney is not exposed in any unit and has been drywalled off. I had a plumber repair the pipe and he said the pipe should not be in the chimney at all.  I haven't been able to determine if the pipe leaves the chimney and exits properly to a drain or just drips to the bottom and dissipates. I used an endoscope and know it goes down at least 15 ft to the 1st floor and seems like it goes lower. Is it ok if the pipe doesn't leave the chimney at all and eventually dries out? Should this condensation line be moved? I've had a large range of opinions between chimney people, a plumber , and a home inspector. There's an odd drop ceiling in the ground unit and think a pipe could run along the area, but don't want to keep cutting holes in the drywall to see if it's not necessary. There's not a convenient location from the HVAC to move the line and the plumber quoted me at 3K to move the pipe and knock down a lot of walls to do it. 

Separately, since the chimney is abandoned, it was recommended I remove the chimney below the roof line. Since this is true other than this pipe, would it be ok to do this if the water really is just dissipating at the bottom of the chimney? I'd appreciate any advice. I just wish I had consistency among the contractors to know if it's ok if this pipe is running down the chimney or not. 

[Pat L.]

We had a HVAC condensate line running out through the siding & into a French drain outside. The plastic line broke & the condensate ran down the 15 yr old cement poured basement wall & it literally spalled the cement 1/2inch deep. Apparently condensate from a Hi Efficiency Fce can have a pH ranging 3.5-6.5, effectively 10x more acidic than tap water.  So it's probably NOT a good idea to have it running down into a brick chimney, hoping it just dries up somewhere before it hits the old ash dump.