Keeping your home as comfortable as possible with your furnace during the winter is important if you live in a cold climate. When your furnace is on almost constantly to keep your home warm, your heating bill will go up. To help you conserve your home's heat better, here are five ways you may be losing and wasting valuable heat and how you can fix them.

Up Your Chimney Flue

When you are not using your fireplace to heat the main room of your home, you need the furnace's heat to warm your home. But, the heat from your furnace can go up and out your chimney if your damper is not sealing right. If there is any crack or gap around the damper inside the flue, heat will get sucked right outside.

Fortunately, you can do a test to see if you have a poorly-fitting damper in your chimney flue. Light a match, then blow it out and hold the match in front of your fireplace opening. Allow the smoke from the match to drift up in front of the fireplace. If your damper is leaking, the smoke will flow toward and up your chimney.

If you have a damper that doesn't fit well, call a chimney professional to install a new, properly-fitting damper. Once they have installed the new damper, you can do the match test again and see the change in air flow as the smoke stays in the room.

Clogged in Your Furnace

One of the biggest reasons your furnace is not warming your home efficiently is because your furnace filter is dirty. 

A dirty filter can cause your furnace to shut off too soon, leaving your home cold, even though there is plenty of warm air inside your furnace. This happens because a dirty filter will block heated air from blowing throughout your home. Instead, the hot air builds up inside the furnace unit, which causes the furnace to sense the heat and shut off. This series of short cycles will heat the inside of your furnace, but not your home.

To correct this problem in your furnace you need to check your filter once a month and change it out when it gets dirty.

Through Your Door

Whether your front door is open or closed, you can still lose a great deal of furnace heat through it. 

If you can see light shining through a gap under your closed front door, you are losing heat through the gap. Any gaps around your door that are large enough to allow a piece of paper to slide through are too large and are letting heat escape your home.

Fill the gaps and cracks around your door with adhesive-backed foam tape to keep heat in your home.

You may also be guilty of leaving your front door open when someone comes to your door. If you open the door and stand in the doorway talking, you are losing valuable heat each second the door is left standing open. Instead, invite your guest in and close the door while you chat. Your guest will probably appreciate not having to stand out in the cold.

Out Your Old Windows

About 30 percent of a home's furnace heat can escape through small cracks and holes around windows and under doors. 

Old and poorly constructed windows can allow heat to escape through any tiny crack or gap in the window. But, you can do several things to help insulate your windows for winter.

You can buy a transparent window film insulation kit that you roll over your window frame to create an extra barrier to keep the heat inside your home. You can also switch out your thin curtains for thick fleece curtains that help insulate your windows better.

Make sure to keep the warm air your furnace creates inside your home, and to reuse wasted heat to heat your home as much as possible.