A DC valve, ran on AC current won't be any better.
What kind of noise?
It can be connected to the central system, or installed as a stand alone system. How open the house plan is determines which way is better.
I came to the conclusion with Electric Light, "if you can't beat em, join em"
I hope he goes to MDTalk.com, then proceeds to the pharmaceutical site, and then complains that those corporate giants are hiding their potions/recipies (which happens to be pixie dust), and we ought to know the manufacturing costs.
Go on 'Ol Electric....:)
At ContractorTalk.com we cater exlusivly to professional contractors who make their living as a contractor. Knowing that many homeowners and DIYers are looking for a community to call home, we've created www.DIYChatroom.com DIY Chatroom is full of helpful advices and perfect for DIY homeowners.