Don't know for sure, but looked at the manual. The flow sensor is just a switch. If it's working, then 2 of socket pins should go from infinite to near-zero ohms when you flex the metal blade so the magnet touches the stalk.
No way to tell which 2 unless you can find a service manual somewhere. But you won't do any damage by trying all pairs.
You might also try to reverse engineer which pins are which. It looks like there are 6. Seems reasonable that there are 2 for each sensor. If so, then this ought to work: 1) look for 2 that connect (1 for each) to the salt sensing blades (don't scratch them) with low ohms. 2) Look for another two that have maybe 10-20 K ohm resistance between them. Those would be the temp sensor. Verify by dunking in cold water to see the resistance change. If you can rule out those 4, the other 2 must be the flow switch.