Connecting to VERY old steam condensate risers

JimGPE_2

How does one connect a new steam condensate line to a riser that has been in service for MANY years - perhaps as many as 70? This is a 42 story building, and I am adding air handlers with steam coils, and I need to connect to the condensate riser system.

My ideas include:

Weld a thread-o-let to the riser and hot-tap it. Can I welt to pipe that is that old? When I hot-tap it is the hole saw likely to crack the pipe?

Take a saws-all and cut the riser between fittings. Remove the two pieces of pipe from their fittings, then install new piping that has a union and a tee in it and connect to the tee. What are the chances of getting the old pipe out of the threaded coupling/fitting?

Thanks, as always.

David Sutton_2

i always like cutting out the pipe ..

and repiping it with a unoin, as far as the old fittings i use a sawsall and cut the pipe within a inch or so to the fitting and then i cut from inside the pipe towards the fitting thread but not all the way thru. then knock out the pice of pipe with a thread chasing chisel . this way if i have a leak i can take it a part and repair it.. hope this help ..David Sutton

JimGPE_2

A familiar technique

On this BB I've heard this technique discussed relative to getting nipples out of radiators. Sounds good for this, too.

Thanks.