NH TL100 coolant heater?

[bluefiat]

I would like to install a hose heater (with pump) to my TL100. It already has a block heater but it´s not working properly.
I am planning to put the new heater to one of the hoses below the oil filter. But which one?

So I would like to know what is the coolant flow direction in those hoses?

Or is there a better place for hose heater? The connections are 16mm (5/8") in diameter.

Thanks already!

 

[bluefiat]

Problem solved. I installed the heater in the outer hose, i.e. the one that goes to the suction side of the water pump (from the bottom of the radiator)