There was a thread about this a while back. I can't find it to continue that one, so I am starting this. Just got an e-mail from one of my suppliers on this add on electric element to a furnace. I am going to give you a link to their web site. Sounds pretty interesting, but you have to have room for it behind the furnace and it is not acheap add on. At their site, you can see a video of the product and several things about it. http://www.rvcomfortsystems.com/index.html# Also got a letter from Suburban about this and they are VOIDING warranty if installed, but RV Comfort is warranting their product. It is going to be up to you to decide about warranty issues. If your unit is new, you might want to wait till your out of warranty from Suburban.