Top 9 Most Important Furnace Maintenance Tips With DIY Solution By Pro HVAC Technician

furnace maintenance

Paying for furnace problems can be quite irritating especially if they occur every now and then. So what should homeowners do to maintain their furnaces?

I have been repairing AC furnaces for a long time now and I know what are those things that you should do to keep your furnace running properly.   

So In this article, I’ll list TOP 9 Furnace maintenance tips that every homeowner should follow. Some of these are minor problems but they can lead to a big one if you don’t operate them correctly. So make sure to read all the tips 

Maintenance Tip No#1: Change Your Furnace Filter 

dirty furnace filter

Furnace maintenance tip number one is to change your filter regularly (every month or two). A dirty furnace filter can cause the furnace to overheat and sometimes it’ll completely stop working.

So how frequently filters should be changed. If you have a 1-inch filter that should be replaced every month or two. I know that a lot of people will say that they last three months.

But let me tell you one thing the only time they’re lasting three months is in the fall when you’re not really using your air conditioner or your furnace or you’re barely using them.

But if it’s negative 30 degrees outside and your furnace is running all the time your filter is going to get plugged up in like three or four weeks.

So if you use your plugged-up filter then the blower motor is going to have a hard time trying to suck the air. Sometimes due to these dirty filters, you’ll end up burning your blower motor.

Also if your furnace is making whistling sounds and when you take that furnace filter out everything stops that’s a good indication that the filter has come to its end cycle. So in general you should be replacing 1-inch filters every month or two.

Maintenance Tip No#2: Duct Cleaning

Furnace maintenance tip number 2 is duct cleaning. Now, this is the most common problem when you have some kind of a home renovation going on.

If you’re remodeling your kitchen or something. Especially if you’re doing sheetrock flooring carpeting that will get your ducts really dirty especially the coil that sits on top of the furnace.

And on top of that you’re not replacing your filter as regularly as you should that a-coil is going to start to get dirty.

Unfortunately, duct cleaning is not something you could do yourself. You do have to hire duct cleaners but a few pointers on that if you’re doing some kind of remodeling make sure you’re replacing your filter a lot more frequently.

Because that will get dirty a lot faster and after you’re done with all the remodeling we do recommend getting your ducts cleaned.

And the most important part about that is to get your evaporator coil cleaned. So if you do hire some duct cleaners make sure you ask them to clean the coil along with all the ducts

Maintenance Tip No#3: Keep Your Return Grills Open

return grills

Furnace maintenance tip number three is to keep your return grills always open. And not blocked by anything and to keep most of your supply registers opened up as well.

I know some people like to close off the supply registers like in the basement for example or in the upstairs room because it gets too hot.

So the rule of thumb for that is you don’t want to close off more than one-third of all the supplies in your house. So if you have let’s say twenty-one registers seven is the absolute maximum that you should be closing but really optimally you should keep them all open.

As for return grills, they’re usually bigger, and return the ones that are sucking air in they will never have shutoffs on them you can’t close a return grill.

And one thing to watch for is that you don’t have any couches or shelves in front of those return grills so nothing is blocking them.

Because they’re sucking the air in if you have some of those return grills blocked then your furnace will overheat. So make sure they’re open and they’re clean.

If your registers have a lot of dust and you can see dust then just get a vacuum cleaner and just vacuum it all out. If the ducts and vents are really dirty you can call a duck work company to clean it out.

Maintenance Tip No#4: Check Your Thermostat


Furnace maintenance tip number four is to check your thermostat. A lot of thermostats will have batteries and a lot of customers won’t be aware that the thermostat has batteries.

Now usually there will be a low battery symbol that appears but unfortunately, most people will miss that little notification until their furnace stops heating.

Or in other times when the batteries get weak that low battery symbol doesn’t always appear before you start having problems. So a good thing to do is to just check out your thermostat pull it off the wall to see if it has any kind of batteries.

And also if you have a programmable thermostat learn how that programming works.

Because if your thermostat accidentally gets bumped into the program mode instead of the manual hold your temperatures can be jumping around all over the place. All of a sudden your thermostat setting will go down to 62 and then back up to 68 and it can be really frustrating. 

Also, Check Our Tutorial On How To Check And Bypass Your Thermostat?

Maintenance Tip No#5: Check Your Furnace Humidifier

Furnace maintenance tip number five is to check your humidifier. So not everybody will have a whole house humidifier but there are quite a few furnaces out there that do have them.

And the only thing you should be aware of about the humidifier is replacing the water panel (Humidier’s filter). If you use your humidifier your water panel will get dirty.

If you press on the water panel and your finger just crumbles right through it that means you should replace that water panel. 

Now talking about the dampers most of the humidifiers will have the damper. So what this damper basically does is closes and opens up the air supply to the humidifier.

So it’ll have a switch or lever-like thing that will operate its opening and closing. So you want your humidifier to close in the summer and running in the winter and you turn it on and off with that switch.

Maintenance Tip No#6: Carbonmono Oxide Detector

Furnace maintenance tip number six is the carbon monoxide detector. In most states by code, you should have a CO detector or a carbon monoxide detector on every single living floor of your house no more than 10 feet away from bedrooms where people sleep.

There are stand-alone carbon monoxide detectors and there is also the duals detector where it’s a smoke detector and a carbon monoxide detector in one.

These detectors are super helpful since you are using an HVAC item at your home. And you should replace them every 5 or 7 years.

Maintenance Tip No#7: Furnace Gas and Power Shutoffs Switch 

furnace switch

Every AC owner should know about the furnace power and gas switch. Most of the time people don’t know these they end up paying technicians for these minor things.

If you look on the sides of your furnace there’ll be a power switch. You’ll have the junction box or the power switch and if you don’t see a power switch at the side of your furnace then just follow the cable that comes out the side of your furnace.

Your gas supply valves will also be on the side of the furnace you just have to look for it. And how to tell if your gas supply is on or off.

So just remember this about the valves if it makes a cross that means that’s off and if it goes with the pipe that means the gas supply is on.  

Maintenance Tip No#8: Check and Clean Your Flame Sensors

Furnace maintenance tip number nine is occasionally a couple of years cleaning the flame sensor. A dirty flame sensor happens to be the number one furnace problem. So periodically cleaning it will prevent it from causing you trouble down the road.

Check Our Tutorial On Troubleshooting Furnace not igniting

Maintenance Tip No#9: Check Intake And Exhaust Pipe

Maintenance tip number eight involves only high-efficiency furnaces. So if you have the plastic PVC exhaust pipe and intake pipe a good thing to check for is to go outside where those pipes are and make sure that those pipes are not covered in the snow.

Especially if you live in a snowy area. A lot of times those pipes get covered by snow and of course, if the exhaust and intake are covered by snow then your furnace is going to stop working. So make sure the area underneath those pipes is shoveled so the snow is not getting too high.

Check Our Furnace Repair Guide

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