Heating   Gustafson Heating installs Rheem and Carrier furnaces.  From the standard 80% efficient unit, to the top of the line 2-stage, 3-stage and modulating 92%-95% efficient furnaces, we can help you select the system that is right for you when it's time to replace and/or upgrade. Here are some ways to get the most out of your heating system: Change your filter regularly   Infiltration is the enemy. Keep doors and windows closed. Be sure fireplace dampers are closed. Caulk/seal leaky windows, doors and gaps.   Denver has 300+ sunny days per year Raise blinds on southern facing windows. Operate furnace fan for constant air circulation and take advantage of this solar gain by redistributing it throughout the home; this will help eliminate those annoying cold spots!   Consider the Gustafson Home Comfort Maintenance Program to keep your entire system in tune.