The chilli plants have grown real tall now, so tall infact that the upper leaves are in the direct pathway of one of the circulatory fans at the top of the greenhouse. The force of the air movement causes an extreme case of evaporation of water from the leaves. Transpirational pull cannot keep up with the moisture loss and so cells in the leaf dry out. At such a level of water evaporation from the leaves it leaves behind the nutrient salts that cannot evaporate making them more and more concentrated until they reach a toxicity level.Leaf burn usually starts with signs of upward curling of leaves. Then there are similar signs to nutrient burn with browning patches and around the edges of the leaf, deformed growth patterns. To stop further wind burn effects i am going to move the fan to another area of the greenhouse. To prevent anything like this happeneing predict the growth of your plants when deciding on positioning of a fan.
