4 Step DIY Furnace Inspection

Checking your furnace is a critical aspect of home maintenance. Here’s how to do it:

1) Inspect Your Filter

The condition of a filter is perhaps the most obvious and easiest to assess indicator of furnace condition.

Furnace FilterHomeowners that take good care of their forced air systems replace these regularly. Those that don’t, don’t.

While you shouldn’t expect to see an immaculate filter, you definitely don’t want to see on that’s overloaded with detritus. Filters clean the air you breathe, but also keep the furnace clean and in good running condition.

Dirty filters cause furnaces to run hotter than designed, leading to accelerated wear-and-tear and premature breakdown. If you find yours is overloaded, swap it out as soon as you can with a fresh one!

2) Investigate Running Condition

Set your home thermostat to heat mode and increase home temperature by about 5° above displayed temperature.

Head to your furnace, and check to see that it lights up.

Old furnaces will generally switch on right away, but if yours is newer there’s a good chance it might take a minute. High-efficiency units generally go through what is known as a start-up cycle, running a blower to create a draft before engaging the heat.

If flames turn on and turn off after a few seconds, its time to get in touch with Modern PURAIR. This is a problem known as short-cycling and requires professional maintenance to fix.

3) Check Your Vents

If your furnace starts up and runs normally, your final task is to make sure that air is making it’s way to each of the areas of your home.

Supply RegisterHead to each of the supply registers (vents) in your home, and ensure they are open and not blocked by any furniture or household items. Too many closed or obstructed registers can impact the proper operation of your furnace, so you’ll want to ensure they are open and clear.

While inspecting each one, you’ll want to assess for dust by visually inspecting the grates, and looking inside the vent for any unusual accumulations. A flashlight is often helpful with this.

If significant dust has accumulated, or despite no obvious obstructions, airflow is not present; there is a problem with your system that requires a professional diagnosis from Modern PURAIR.

4) Plenum Space Test

After the system has been running for about 20 minutes, head back to your furnace.

Your furnace Plenum is the ductwork directly above your furnace. Heading vertically to feed the rest of your system, you’ll want to carefully place your hand on it to assess it’s temperature.

It should be warm, but not uncomfortably so. If it is, chances are there is something wrong with your system that causes it to overcompensate. To find out what it is, call Modern PURAIR