97 Accord SE 2dr w/ H22A

Just replaced my heater core, something that I noticed to be leaking during my motor swap earlier this summer. Heater core is in, was a huge b*tch, and I'm happy to have walked away with all my fingers. Thought I was good to go and BAM... thermo rises towards the red while I'm running the car in the driveway. Within minutes I find that the fans aren't switching on. With the new heater I am able to battle the overheat, but its not how I want to spend my winter. I jumped the sensor plugs for both the thermo sensor and the upper-rad hose sensor and the fan kicks on in each scenario (car ON for the one and car OFF for the other). Fans kick on with the A/C on. htf are both my sensors kaput when they were working fine before the heater core? Not to mention these sensors are only a few months old.

My main issue is that this is too coincidental. I would like to know if anyone has any idea what would make this happen, or if I should be aware of an underlying problem. Granted if the fans go on when sensors are jumped, the relay and fan control module/timer are functioning (right?). If anyone has any clue, I would really like to know what the deal is.

P/S: Are the two sensors identical part #'s or are they different?