While you were enjoying your summer, you probably didn’t pay much attention to your furnace since you didn’t need to use it. With the colder months on their way, though, it’s time to think about your heating system and get it ready for the fall and winter.

At Grandmark Service Company, we can make sure that you know what to do. Here are some tips that will help you ensure that your furnace is prepared for the changing seasons so that you and your family are comfortable in your home during the colder months.

Giving Your Furnace a Test Run

The first thing you are going to want to do to ensure that your furnace is ready for fall and winter is to give it a test run. To do this, turn on your system and set the temperature above your home’s room temperature.

There are four key indicators at this stage to look out for that could point to your furnace having an issue:

  • Noises
  • Odors
  • No heat
  • Continuous running


When you turn on your furnace, there is the possibility that you may hear a noise that is unfamiliar to you. If you hear a high-pitched, continuous sound, this could be from the air return not working properly. When there is a flapping or rattling sound, this could be from debris that has settled in the duct or from a part that is loose. If you hear squeaking or squealing, this is an indicator that a bad belt is the problem. Finally, if you notice a metal-on-metal sound, that means there is potentially a part of the blower system that needs to be adjusted.

Should you encounter any of these noises, it is time to call in a professional.


If you encounter an odor when you are testing your furnace, it may just be dirt and dust that has collected during the warmer months and is now burning off. This is completely normal and should stop within a few minutes to a few hours. If the burning smell does not stop, though, this could be an indicator that your system is overheating. This will be more apparent if the smell is like burning plastic as this points to the possibility of melting components or wiring.

If there is a rotten egg smell, this could be an indicator that there is a natural gas leak. If this happens, turn off your gas supply if you are able to do it safely, exit the house, and call emergency services as well as the gas company.

When there is a musty or damp smell, this could mean that water has somehow gotten into the furnace. This is potentially from the furnace drain pan having a loose connection.

Should you encounter a smell like car exhaust, this could mean an issue with your furnace being vented.

No Heat

If you turn on your furnace and you get no heat, this could be due to a few potential issues. First, it could simply be that your thermostat is set to the wrong settings. This is actually one of the most common issues. You will want to make sure that your thermostat is set to HEAT and not COOL as well as AUTO. If this does not work, set your temperature a couple of degrees higher. If there is still no heat, bring in a professional.

A lack of heat could also potentially be due to an airflow issue. This often means that there is some type of obstruction.

Another possibility is that something could be preventing your furnace from getting gas. If there is no fuel to combust, then you will not get heat.

Continuous Running

If you take your furnace for a test run and it will not shut off, it is likely one of the following issues:

  • A problem with the thermostat
  • Dirty air filter
  • The blower is faulty
  • Air ducts are leaky

Aside from there being a dirty air filter, any of these issues will be difficult to determine on your own and should be addressed by a licensed professional.

Changing the Air Filters

Your air filters are typically protected by vent grills in your walls or your ceiling. Otherwise, sometimes there is just a single filter that is in the HVAC system directly. These filters are meant to be changed every few months, so they should definitely be replaced before heading into the fall and winter.

Check Your Carbon Monoxide Detectors

Carbon monoxide is a gas that could lead to dangerous health situations or worse. Before you run your furnace throughout the colder months, you are going to want to make sure that you have carbon monoxide detectors that are set up and working properly.

Professional Routine Maintenance

Before the fall and winter are upon you, you should have a licensed professional take a look at your system. Even if there does not appear to be a problem during your test run of the furnace, it is a good idea to have a technician make sure everything is looking good. This is best for your safety and that of your loved ones, and it also gives you the opportunity to catch any issues early before it is already cold.

One of the things a licensed technician will look at is the heat exchanger. This involves cleaning and vacuuming the unit while it is disabled. During this process, the technician will also check for any cracks.

A professional will also take a look at your chimney to make sure there is no carbon buildup or any small animals that have settled in.

Another thing a professional may look at during routine maintenance is the blower motor. They are going to want to make sure that it does not need lubricating. If it does, they will typically lubricate the bearings.

During a routine maintenance check of your furnace to prepare it for winter, your service technician will also do things like inspect and clean the air ducts, check and adjust the fan switch for ideal velocity, and check the gas line for any leaks to ensure safe operation.

Once you have given your furnace a test run, cleaned your air filters, checked your carbon monoxide alarms, and had a routine maintenance visit from a licensed technician, you will be ready to embrace the chillier time of the year. You can do so with confidence, knowing that you will be able to enjoy the season in comfort.

If you are in Fresno, Kern, Stanislaus, or Sacramento county, look to Grandmark Service Company when you are ready to get your furnace prepped for the fall and winter. Our team of professionals is here to meet all of your heating and cooling needs. We are also experts in other services, such as roofing and solar installations.

Get in contact with Grandmark Service Company to make sure your furnace is ready for the cold so that you and your loved ones don’t spend a single day in discomfort.

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