There’s quite possibly nothing worse than having furnace problems with the cold weather coming on, or when you are in the middle of some of the coldest weather of the season. Murphy’s Law aside, there are a few things that you can do to fix your furnace yourself, or at least make it work long enough to find someone to come out and fix it permanently for you. Carol Flynn Heating and Cooling, Inc. has a few ideas when it comes to diagnosing your own equipment.

Troubleshooting Furnace Problems: DIY Fixes and Expert Solutions for a Warm Winter

First, check the easy things. These are usually the things that embarrass you when you have to call a repairman and all they end up doing is flipping a switch. So…check to see if your thermostat is actually on. Sometimes normal wear and tear, someone bumping into it, maybe the kids hit it with a ball, or someone decides to turn it off because they are hot/cold may have moved your switch to the off position. Simply flip it back on and you are in business. This sounds simple, but many people ‘think’ they have it turned back on, and they don’t. Look at your thermostat and make sure the switch is set to the ‘heat’ rather than the ‘cool’ setting. Then check the temperature setting. It could be that you don’t have it set to the proper temperature and that’s why it hasn’t been coming on. Make sure that it isn’t your thermostat that is off by using a room thermometer (like for outside), then see if your thermostat registers within a 2-3 degree reading of that. If it doesn’t, then it might not be your furnace, but rather your thermostat. Luckily, Carol Flynn Heating and Cooling, Inc can also take care of anything minor like this and even suggest a better thermostat that can be adjusted using your smartphone.

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Secondly, check to see if the breaker or fuses are still in the on position. Sometimes when there is a lot of thunderstorm activity in the area, or an unusually heavy ice storm, then the breakers or fuses can be blown or tripped. Locate your electrical box (most are located in the garage or a closet) and see if the breaker switches are all the way over to the left (or in the on position). Flip them off, then back on if you are not sure.

Third, check your filters. Something as simple as a too full filter can cause some types of furnaces to shut off. Carol Flynn Heating and Cooling, Inc. suggests changing them at least every few months, and ideally every month if you can remember. Remember that dust and dirt restrict air flow so if the filter gets too clogged the heat exchanger will overheat shutting it down (and then you become very cold). Also, a dirty filter can cause buildup on the exchanger making the furnace less efficient, cost you more money, and have half the life expectancy. Most owner’s manuals show where the filter is and how to change it, but if you’ve lost your owner’s manual you can either call Carol Flynn Heating and Cooling, Inc as they are familiar with almost every kind of furnace there is (they’ve been in business for more than 25 years!) and they’ll be happy to tell you. Or, you can do a quick internet search and most likely find it there, too.

Fourth, if you have a furnace that is powered by fuel, then make sure that the gas has been turned on and that the chimney exhaust flue is clear.

Fifth, if you know how to flush the drain lines this would be a good thing to do as they could have become clogged over the summer months. Carol Flynn Heating and Cooling, Inc. can do this for you, also, for a nominal fee. Along those same lines is the blocked or leaky ducts that can restrict air flow.

Lastly, if you smell gas at all deal with it immediately. Don’t light any matches or have any open flames around your home until it is taken care of and consider evacuating your home until the repairman comes. If you can find the gas supply valve, which is usually located by your gas meter on the gas inlet pipe, rotate the valve one quarter turn so that it is off. Call Carol Flynn Heating and Cooling, Inc as soon as you and your family are safely away.

If you’ve tried all of these steps and the furnace is still not heating correctly or well, then it is most likely time to call Carol Flynn Heating and Cooling, Inc. They are some of the most called upon repair people in the business and certainly in the Redwood City area. With more than several decades servicing the area, they can best detect what the problem is with your furnace, and either repair it on the spot, or give you the news that you will need a new system. A rule of thumb is that if your system is more than 10 years old you really should consider having a new one installed because the newer units are much more efficient and that can translate into hundreds of dollars in savings over the entire year.

Carol Flynn Heating and Cooling, Inc have very knowledgeable professionals who can guide you in determining what sort of furnace would be right for you, your family, and your budget. What is nice is that they will tell you which unit is priced for your budget and will match you with a brand of furnace that will meet the load needs of your size home. Many times people believe that bigger is better, but this is definitely not the case. Allow the good people at Carol Flynn Heating and Cooling, Inc to help you with this very important decision. Their trained professionals have to go through a lengthy training program in order to be able to not only repair your unit, but to recommend those that would work best for you.

This season, don’t get caught out in the cold. Let someone from Carol Flynn Heating and Cooling, Inc help you troubleshoot any of your furnace issues, or better yet, come out and take care of it for you.


How Does a Central Forced-Air Heating System Work?

  • It pulls colder air to the internal ductwork and pushes it into the furnace, where the air is filtered and heated. Then it distributes the heated air through vents into different rooms throughout the home.

What are the Fuels for Furnaces?

  • Natural gas (most common in Bay Area homes) 
  • Oil
  • Propane
  • Coal
  • Wood
  • Electricity & other combustible materials
  • Learn more about furnaces

How Furnace Efficiency is Rated?

  • The measurement used for determining a furnace’s efficiency is an Annual Fuel Utilization Efficiency (AFUE) rating. Most new furnaces come with a posted rating from the manufacturer, generally in the form of a yellow “Energy Guide” label attached to the unit. AFUE ratings for new furnaces generally range from 78% to 96.7% for Carrier’s SXC model. Learn more

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Welcome to Carol Flynn Heating & Cooling! Let us design and install a highly efficient heating and cooling system in your home and/or office. Superior products and quality installations for less.

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Carol Flynn Heating & Cooling

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