Product review (1 stars): Zephyr doesn't take responsibility for their products under warrantee and good lord they are so very costly
This very expensive ($1000+) unit is not worth it.  When it runs, it whistles -- and when you call for service from the manufacturer they tell you it is the installation and charge you $140 for the service call.  My installer removed all of the venting and ran the unit -- and it still made the whistling noise.  It is NOT an installation problem.  Now I am stuck -- and out an additional $140.  Zephyr doesn't take responsibility for their products under warrantee and good lord they are so very costly.  DO NOT GET one of these -- choose another.  Buyer beware.