Comprehensive Furnace Maintenance Guide

Published by 
AllThingsHVAC
Last updated: 
November 9, 2015

Heating and cooling systems are the best solutions to keep your home a pleasant environment both during winter and during summer. While maintenance is usually kept to a minimum, to make sure you’re looking after your furnace’s longevity, take notes on these ABCs of furnace maintenance. Propane gas furnace maintenance or oil furnace maintenance? Regardless of the type of system you own, you can keep everything in check with a few preventive steps you can repeat every month or each winter.

What can go wrong?

Furnaces are reliable and you shouldn’t have any problems with them. However, a furnace that won’t turn on or give off heat indicates there is a problem with the heating source, the thermostat, or the distribution system. If you’re having trouble running your air conditioner, boiler or furnace, there could be an issue at the source. This could be happening either because fuel is unable to get to the unit or, if fuel does reach the system, it fails to ignite and turn it on. On the other hand, if you can turn on your heating system, but you don’t feel the heated air coming into your rooms, you probably have a problem with the distribution system. A defective thermostat could be overturning your settings by switching the system on and off and throwing the preset temperature completely off track.

Comprehensive Furnace Maintenance Guide

Furnace maintenance checklist

HVAC repair costs can set you back a few hundred dollars. Most of the time, the problem is not that serious and can be fixed by anyone who can follow some simple guidelines. If you find your furnace humidifier has stopped working properly, or that the steam boiler is not giving hot water, don’t rush to the phone to call a furnace repair pro to look at your heating system. Here are some tips and tricks on how you can take care of your unit in order to avoid the additional furnace maintenance cost.

  • The first step in pinpointing the issue with your furnace is to check if it’s receiving power. Take a look at the main panel. Are there any tripped circuit breakers? Your furnace might have its own direct power entrance, on another panel, or even a fuse mounted on the unit or within. Check these as well, to rule out the power issue.
  • Most furnaces have a “reset” button. Before pressing it, wait for the unit to cool down. Repeat the process if the heating doesn’t restart on the first try, waiting 30 minutes between each attempt.
  • Some units might have an individual switch. Check to see if it’s on.
  • To rule out the thermostat isn’t faulty, take a look at the settings and try to raise or lower the temperature to see if anything happens.
  • Sometimes, the simplest issues are to blame. For a unit that uses natural gas, make sure the supply is turned on; if the system uses oil, check the supply isn’t running low.

Safety first

Making sure your heating or cooling units are working properly isn’t dangerous, but there are some safety measures you should keep in mind before tackling the issue.

  • Before starting working on the faulty unit, you have to turn off the power. Head over to the electrical panel and remove the fuse that fuels the heating unit. If you don’t know what circuit breaker to trip, the safest method is to turn off the power for the entire house. If your furnace uses a separate electrical panel, perform the above mentioned steps there.
  • If your air conditioning service or furnace unit trips the circuit or causes the fuses to blow each time they are turned on, you have a problem within the electrical system.
  • If you smell gas in your house and your heating system runs on gas, leave the windows and doors open and get out of your house. To prevent a blast, don’t shut off the gas and don’t switch on the lights. Call the gas carrier to let them know about the gas leak as soon as everyone is safely out of the house.
  • Experts recommend you schedule an annual professional check-up for your heating system. The best time for the inspection is when the heating season ends. To kill two birds with one stone, perform the professional check-up for your air conditioning as well.

Comprehensive Furnace Maintenance

Tips on cleaning a furnace

Whether you acquired your home heating system from Lennox or Trane and you’re a client of Enbridge in Calgary or other energy delivery company in Toronto or Chicago, you’ll still have to deal with dirt and dust. These two can affect the furnace’s efficiency and sneak its way into the key components of the unit: the motor, which can overheat, the filter, which can get clogged, and the blower. It’s recommended you replace the filter before the heating season starts and clean it periodically, at least once a month after you turn on the unit. To check on the filter’s condition you can take it out of the furnace and look at it in the light. If it’s extremely dirty, don’t postpone replacing it, even if it was only used for a week or two.

Keeping the blower and the pulleys clean is just as important as replacing a dirty filter. In order to clean the blower, you have to take out the filter panel so you can reach in front of the furnace. If you need to disconnect any cords or wires, don’t forget to mark them, so you know how to reassemble them in the right order. To clean the blades of the fan, you can use an old toothbrush, vacuuming the dust and dirt on the belt. The motor tends to clog with buildup, so it’s always ideal to clean it with a damp cloth and remove the dirt and dust.

Lubricating a furnace motor

Furnace motors can easily overheat, causing the entire unit to turn off. To keep the motor working at full power, lubricate it regularly by applying motor oil into every port. Don’t be too generous with the lubrication process. If you add more than necessary, you risk over-lubricating, and you’ll end up doing more damage than good. To reach the ports, unscrew the plates and use tiny amounts of oil.

Guide to Comprehensive Furnace Maintenance

Replacing your drive belt

We’re tempted to wait for the drive belt to break down before replacing it, convinced that as long as it’s working, it’s as good as new. But if you didn’t replace your furnace’s belt in the last three years, and you’re ready for some DIY, you should at least keep a spare one in your house, just in case. A busted belt can cause other problems, like reduced airflow. You can buy a replacement belt online or at any hardware store. Before you start your handiwork, inspect the belt to make sure you replace it with the same model. You’ll find a series of numbers and letters on the outside of the belt, which indicates the exact model and type.

The first step is to power off the unit completely from its switch button or from the control panel. Then, to access the blower, remove the panels and any screws holding them together. Don’t rush into things, the old belt shouldn’t be forced out. Pulling it out could damage the motor or even the blower. Instead, use a marker to make a note of the motor mount’s position and with and wrench, start loosening the bolts. This will help you take out the belt easier, without damaging other parts. Take advantage of the occasion to clean the pulleys and the blower, which often gather dust and dirt. You can also lubricate any oil ports, avoiding staining the copper parts within the motor. To set up the new belt, begin with the smaller pulley and place the motor mount back, according to the mark. The belt shouldn’t be extremely taut, but it should be firmly stretched out. Finish off by reattaching the screws and the panels and turning on the circuit breakers.

Additional tips and tricks

When it comes to furnaces, seasonal cleaning and care will take you a long way and even spare you additional costs. Regular filter cleaning will prevent dust and dirt reaching the blower and slowing down the unit. You’ll never have to clean the blower as long as you clean or replace the filters as soon as they get clogged. Never use a furnace without a filter. This won’t only damage the main parts of the unit (the blower wheel, the furnace controls and the air ducts), but the charred air will also soil your walls, upholstery, and carpets. Lubrication is unnecessary for furnaces that don’t have oiling ports. For those with oiling ports, a maximum of 20 drops is more than enough. Most furnaces that break down require uncomplicated solutions. Frequently, a tripped circuit breaker, a clogged filter or a turned off switch are the causes of the malfunction. If you want to roll up your sleeves and save some money, instead of calling a professional service person, you can investigate the issue yourself. Make sure to follow all the safety advice before getting to work. Furnace maintenance will not only discard unnecessary expenses, it will also prevent unpleasant surprises when you least expect them.

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