How do I find out if I have a dual heating system?

[rgaila]

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Original Poster: Kendra Horner 

How can I tell if I have a dual heating system? Do I need to let professional install? 

[rgaila]

You should be able to find that out in your system's owner's manual. If you're not sure about it, a professional install is a good idea.

-From Joe Ellet, Silver Product Expert.