Is there any way a lineset can be installed under concrete? i've been told both yes and no and don't know who to believe. we are building on a hillside and the lower level floor is 3 to 4 feet above grade. we live in northern ohio (if that makes any difference) and will probably use the air less than a dozen days a summer. my bryant/ hvac guy said that bryant will not allow it because of slugging problems (i contacted bryant and they didn't know and said to ask the dealer). is this true? if yes, what is the likelyhood of this happeneing? if this were to happen, what could be done to correct it? i was going to install a 4" pvc sleeve to run it thru. not sure of the best way to insulate it. any suggestions?

on another matter- do the round in-duct motorized dampers work very well. we will have several rooms that will not be used on a regular basis. talked about zoning the system, but at under a hundred bucks each, i thought this would be easier and more cost effective. what options would i have to control them? would a simple 115v lighting switch work? my heating guy said he has just started using them.

thanx for your reply and have a great day! mike