Water temperature gauge

Finally installed a self powered temp gauge. Battery life good for a year. Range 0-120 deg cel. Sampling every 5 sec. Accuracy +/- 1 deg C. Gauge has waterproof done with silicon.

 

No hose cutting. Just CA a modified RC propeller (5mm shaft to hold the thermistor sensor) with bigger surface area. Using an infrared temp. gun and check the temperature difference is only 1 deg celcius from that of the radiator.

Quite satisfy with this. At around 90 deg cel., the radiator fan will switch on.

I was stupid to CA the sensor to the radiator water out side. I guess the radiator coolant in side is more appropriate. The tempeature on each side has a difference of ~10 deg cel.