Heating / Engine Cooling Problem?

[wmostellar@xxxxxxxxxxxxxx]

Help - I'm in Dallas for the week on business.  During the trip my heater wouldn't work (blow hot air) unless I was above 4,500 PRM.  The fan, AC compressor, etc worked fine.  The engine warmed up properly and stayed right at it's normal temperature (1 needle to the left of center).  Is my engine staying cool?  Do I need to have it looked at before returning to Atlanta?  I'm at DFW airport and can barter a tour/demo of a Learjet simulator.  Thanks in advance!
Bill - 92 318ic (E30/M42)

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