We are purchasing a house built in 1926. It currently has steam gas heat and no a/c. We would like to install a combination system that uses small tubing that can easily be run thru the house. The house has 3 floors (not including basement, including attic) . There is now a boiler room in the basement but the attic is huge, finished and there are a couple of closets where a system could be installed. I have several questions:
1. Are these systems efficient? Are they noisy?
2. What's the approx. cost of buying and installing?
3. Is there any other alternative that would be better and not obtrusive once it is installed?
4. Do these hi velocity systems run on gas or electricity? We want to minimize the cost of running this. Will change windows and foam insulate attic.
5. How do we find a reliable and dependable installer? I just heard of 2 different families having to fire their HVAC people for the huge mistakes they made.

I appreciate any help you can send our way and look forward to your comments and suggestions.