I have a couple of questions I need help with.

1. I have a building that is 20 storys tall, chillers in basment. I want to remove an existing DK and install a used YK. The 19DK has 150 lb water boxs and piping but the pressure in the basment is at about 170 lbs. What is the ruleing on exceding the 150 lb rating. If I drop the YK in and by a freak accident the water box blows could I be liable? Is it against code? Are the existing machines against code? I have adusted the make up in the penthouse to 10psi to keep the pressure at 170 in the basement.

2. The 19DK is 400 ton. I need to look again but I think the design delta T is 14 deg and the chiller is a three pass. Chill water pump is I belive around 650 to 700 GPM. The YK is two pass 10 deg. What are your thoughts on droping in two pass to replace the three pass? Just trying to think through the problems I might encounter before hand. The York is a 52 in 42 out at 960 gpm.

Whatcha think?