Hmm, this internet photo URL appears in the reply box, but maybe not to the reader.
This is my condensor. The seawater enters the top double loop and there are 90 degree attached metal tubes, which I presume go to the condenser coil, nd carry flow away from the coil back to the larger outflow tube.. It would seem a small fraction of the cooling water flowing through the top tubes flow 90 deg down the small caliber tubes to the coil.
Best to check seawater flow at the 90 degree pipe attachment; vs the plastic hose to metal pipe connection on the larger top seawater tubes?
The temp of the larger tube is only 3 deg higher than inflow (88-90 deg F) , but the little tube I believe is from the condenser is 106 deg.