Heat difference between recirc and ram air

[johnny_quattro]

When Auto is engaged on the Climate Control, it never seems to get that warm in the car even if you set it to high [HI]. I had a play with my controls last night whilst warming myself with the seat on Arctic Mode 6, and discovered that if I set it to Recirc (either of the two buttons with the circular swooping arrow to the right icons) and I get hit with Saharan levels of warmth. Switch it back to full Auto and I hear flaps moving and the temperature goes back to reasonable warmth levels.

Any ideas?

P.S. I do have a replacement control panel ready to fit. Ordered this from Maria a few months ago, as my climate control sometimes lights up like an Xmas tree when I start the car, so perhaps it's that.