PACK LIGHT 737 NG
In regards to the PACK LIGHT annunciation on the 737 NG, I need some clarification as I believe I am completely confusing myself.
In the situation that the PACK Light illuminates as a result of PACK overheat (so does not extinguish after Master Caution reset) As per the QRH you select a warmer temperature on ALL the TEMP selectors in order so that AFTER Trip Reset you reduce the load on the PACK (as would be the case on a HOT day and the pack was working too hard to cool it down)
I have read that BOTH air mix valves are driven to full cold and TEMP selectors are disabled.
My questions/what I need clarifying is
When it says BOTH air mix valves. Does each of the TWO Packs have two air mix valves each or are these TWO air mix valves common between BOTH Packs. What is confusing me is that if it is a case that each PACK has TWO air mix valves and in this case due to an overheat the PACK shuts down and its two air mix valves drive full cold WHY then could I not still use the TEMP Selectors for control over the other pack that is still operating.