Pressurisation on B73-

[millerman]

This morning we had a new generation 737 at FL370 requesting descent due to pressurisation problems.We descended him initially to FL330 and the pilot said he was happy to maintain this level, which he did.We were too busy at the time to ask the nature of the problem and as he was happy we sent him to the next sector.
Has anyone any ideas what may have been the problem and why only 4000ft level change seemed to solve it. (I always thought if it was a pressurisation problem you descended as low as possible!).
Thanks in advance

[Right Way Up]

He might have had a pack or engine bleed problem. Forgive my memory but preflight failure will restrict you to FL290(?) according to the MEL. However with an inflight failure you are not restricted, but airmanship might dictate you pick a lower altitude just in case of further failure.