The Regency Energy U31 B-vent gas fireplace insert is well suited to installation in older homes. This mid-sized gas insert provides ample radiant and convective heat for most mid-sized living spaces. The U31 gas insert includes a variable speed blower to help circulate the warmth of the fireplace throughout the room. Rest easy knowing that you are buying a quality gas insert with Regency’s industry leading limited lifetime warranty. Stay warm even during the worst storms with the U31 gas fireplace insert that continues to operate safely without electricity.