As the holiday season kicks into full swing, it's likely that your home will be filled with guests coming to stay for a weekend or two — and with holiday guests comes a little preemptive holiday cleaning. However, among the dusting, vacuuming, and polishing, there's a hidden source of dirt lurking within your home: your heater.

It can be hard to tell when your filter for your heater stops doing its job and starts keeping all of the grime in your ducts and even in the air, so if you're prepping your home this winter for a little festive fun and want to leave the dirt behind, then here are four signs your air filter needs to be replaced before the guests start to arrive.

1. Check the Color of Your Air Filter
As with Santa and Christmas bonuses, seeing is believing, so your first step should be to look at the filter for yourself. Clean filters are white or off-white and have no noticeable buildup, while filters that need to be replaced are usually varying shades of grey and have dust visibly built up along each ridge. If you're not sure if your filter is clean or not, then you should probably replace it, just to be safe.
Replacing the filter may improve the air quality throughout your home.

2. How Long Does It Take for Your Home to Warm Up?
When the nighttime chill starts to set in, you'll want your home to heat up as quickly as possible, but if you're spending hours rubbing your hands together and waiting for heat, the problem might lie in your filter.
When the filter is dirty and clogged, air has a harder time traveling past it and into your home, meaning that less air, in general, makes it out to you, slowing any temperature gain you might want. If your heater takes more time to heat your house, then that means the heater is on for longer, which can quickly increase your electric bill.

3. Is There a Weird Smell?
The holidays hold many distinctive smells — gingerbread, peppermint, pine — but one smell that you don't want in your home is a burned or burning smell. If you're constantly smelling a burned smell, then there's a good chance that the smell is coming from your heater's filter.
Whether it's the blower motor or the furnace filter itself overheating, a burned smell means that your filter isn't doing its job anymore and needs to be tossed.

4. Are There Weird Sounds?
Over the holidays you home will probably be filled with chatter, holiday movies, music, laughter, and the sounds of wrapping paper being torn, but one sound you should be on the lookout for is a high-pitched whine coming from your heater.
This whistle is an obvious sign that your motor is struggling to suck in the air or that your airflow, in general, is restricted. Both of these symptoms can happen because of a dirty filter. If you hear a constant high-pitched noise, it's time to replace your filter.

What Else Could Be Wrong?
The goal of appliances such as your heater is to make life easier, not harder. If your home shows all the signs of a dirty filter, but your filter is still shining white, then it's time to call in the professionals, preferably before you start slicing the holiday ham.
Visit the experts at APD Appliance Parts Distributor today for great deals on parts for your heater or other appliances to ensure that your home’s heater works as well as possible as the cold weather begins to blow in.