G'Day Nick,
Food for thought isn't it?
I don't know if I should call this a guess or an inkling of a thought but:
Maybe the radiator is to big for the flow rate?
Consider water flowing through a grate into a drain, if the flow rate is low the water trickles down through the grate only at the point closest to the inlet. Not until the flow rate is high is the whole grate used.
Let the debate begin
Food for thought isn't it?
I don't know if I should call this a guess or an inkling of a thought but:
Maybe the radiator is to big for the flow rate?
Consider water flowing through a grate into a drain, if the flow rate is low the water trickles down through the grate only at the point closest to the inlet. Not until the flow rate is high is the whole grate used.
Let the debate begin