The TCS Y chiller that has a leaky seal (SN# 0110193301120813) has been replaced with the spare (SN# 0127640801150617). New quick connect fittings were used as the old ones had been cross-threaded. I used the old settings from the original chiller on the spare chiller (attached here, couldn't find a document containing them). No leaks or water level dropping could be detected after several hours of running, will recheck tomorrow.