Heater battery

Hi...My first topic here.

I believe that the heaterbattery in my -75 dart gt is clogged!Or could it be vacuum issues?There is hot coolingfluid going in and much cooler in the outlet,but almost no heat inside the car.Thinking about getting it out for a good cleaning.Or is there any good ideas of getting it rinsed mounted?Sorry if there is any faulty writing,I'm from Finland...:toothy10: