Furnace Filters

Replacing a furnace filter is, in most cases, very easy and very rewarding. It will improve the furnace's energy efficiency and improve indoor air quality.

I say "in most cases" because, well, some jobs are easier than others. Most furnaces have filters that come mounted in a handy cardboard frame. Here's an example of one, in case you haven't seen them before. Manufacturers suggest changing furnace filters monthly during the winter, and most are cheap enough that this isn't an unreasonable request. For these furnaces, you just slide the old filter out, note its size, go to the hardware store to buy a new one and then slide it in. Easy-peasey.

But not mine. Oh, no, nothing so simple for the Green Tenant. The furnace in my apartment was installed in 1984 and doesn't have the handy pre-framed filter.

For mine, one must buy a roll of fibreglass material and cut it to size. Still, it's not hard.

First, open the bottom compartment of the furnace (usually they just slide into place) to reveal the filter chamber. Then remove the carriage holding the filter. In this case, it was a simple matter of pulling the top edges in slightly, then sliding it out.



The filter on this model is held by clips on either side. They clip onto the mesh and are released by sliding (on this one, one side goes up, the other goes down). Then peel off the old filter. This one obviously hasn't been replaced in ages. Eeew.







Lay the old filter on the floor. Lay the sheet of new material over top, then cut it to size with an Olfa knife, box cutter or scissors.








Clip the new filter into the carriage, then slide the unit back into place. Follow any directions on the package (it might tell you which side of the filter to position facing in).







This won't make a 24-year-old furnace particularly energy efficient, but it will help the fan circulate warm air more easily. And your lungs will thank you, too.