I dialed down EY purge air so not all five compressors are running, to help with temperature control in the mechanical room. After adjustment one pump turned off. I think we nominally run on just three at a time, but the soft cover on BSC 10 was not billowing very much so I didn't want to reduce flow much more.

DP measured -16degC. Not great, and it maybe would have dropped slightly more if I had more time to measure before rushing to meetings. It's also raining outside.