Boiler central heating return temperature?

330d

I have balanced my central heating system in my house. All the heaters are showing a temperature at the top between 55-60c.

And at the bottom they are 10-12c temperature drop. Reading online this is what is recommended.

My boiler outlet temperature is currently set to 70c. I know this is higher than what is recommended and not very efficient but I noticed the heaters do heat up much quicker Vs 60c setting.

But what I'm confused about is it's showing a return flow temperature of 67c. I was expecting the return temperature to be much lower than that. Surely the water is not loosing 3c heat after heating my radiators?

Do I need to somehow lower the return temp?

Thanks 

sheenas

The idea is that the boiler runs for longer at a lower temperature. This does mean it takes a bit longer to heat up but runs more efficiently. The boiler will what’s Called modulate. The limiting factor is radiator size , small radiators not being able to heat a room, if you turn the flow temperature down to much. I run mine at 55c you could try lower if you like, but I would keep it above 50c Thu.