I had a 10 seer heat pump that was replace with a 13 seer heat pump. The air handler or coil was not change it is a 10 seer. My problem is I have 1039 sq ft. my den and bedroom are the farest away from air handler the den has no air flow and bedroom has very little. What is the problem.

The actual problem is hard to say. Dirty air filters, dirty original indoor coil, improper duct connections or the coil inside might be icing up due to the mis-matched indoor coil.

If the indoor coil does not have a thermostatic expansion valve installed and you run a 10 SEER coil with a 13 SEER outside unit major problems can and do occur.

A 13 SEER outside heat pump should never be installed with an old 10 SEER coil. You might be able to get away with it on a strait A/C system but not on a heat pump. Whoever installed your new outside unit did you a great injustice and I suggest you call them back to do the job correctly.

Here are a few files on the subject of mis-matching new outside units to old coils.