How to replace the air filter on your AC

You've been shut up inside, windows closed, keeping warm and cozy all winter.  But now that Spring has sprung, do you really want to keep breathing all that stale dusty air that's been building up in your heating/AC filter all winter long? As a general rule, you should really replace the return air filter on your central heating and cooling system every 1-3 months so the unit will work at […]