Furnace Heating Tune Up Checklist

Check for carbon monoxide – Carbon monoxide is a gas that you can’t see, hear, smell, or taste. In other words, it’s undetectable and extremely dangerous. If you are exposed to enough of it for too long it can be fatal. Since furnaces are powered by gas, they naturally emit carbon monoxide as a bi-product of the fuel burning process. A properly maintained furnace will surely funnel the toxic gas out of your home. However, if the furnace is neglected, cracks can form on the firebox which is where the carbon monoxide is formed and it will leak into the home. This is the most important part of a furnace maintenance as safety is always the number one priority. Another way to ensure your home is safe from the deadly gas, is to purchase a carbon monoxide detector. Whether or not you decide to have scheduled maintenance on your system, we highly recommend to purchase one and have it installed in your home.
Thermostat – The thermostat is the controller responsible for turning your system on and off setting your desired temperature. If your thermostat is not calibrated correctly, it can cause the unit to work more even after you’ve reached the desired temperature making you get either too cold or too hot. This directly causes you to spend more on your electrical bills. In order to prevent this, the technician will check the accuracy of your thermostats and calibrate it as necessary.
Inspect for combustible material around furnace – Fire prevention begins with checking for fire hazards. A gas furnace should not be placed by any materials or items that can catch fire. During a routine maintenance, the technician will thoroughly check the placement of your system and anything around it to ensure the safety of your family and system.
Ignition system – There are 2 types of ignition systems to start up your furnace. The less common of the two is called the intermittent pilot, which uses an electric spark to turn on a pilot light when it is needed. The pilot light has a separate gas line and its own valve. When you turn on your furnace, the pilot light comes on which sends a signal to open the valve to the burners in your heat exchanger and they are then lit by the pilot flame. On the other hand, the more common system is the hot surface ignition system. This system completely eliminates the pilot light and allows electricity to directly ignite the burners. When it reaches a set temperature, the gas flows to the burners and the hot surface of the igniter ignites the burners. This method is clean, simple, and energy efficient! Now unfortunately, these igniter systems can fail overtime. Premature failure can be caused by a number of factors such as improper handling (oil from the skin got onto the element), an improper igniter was installed in your system, it’s the end of it’s life cycle, the voltage in the electrical circuit is too high, and lastly, a dirty air filter (the root of most problems in the HVAC system). In order to catch this before your furnace breaks down or is permanently damaged, you should schedule a system maintenance every 6 months.
Exhaust system/combustion vent – Your furnace generates heat and toxic gasses during it’s heating cycle. The exhaust system in a furnace is responsible for safely venting the combustion gasses and air to the outside of your home. It does this by using a damper to regulate the pressure between the air from your furnace and the outside air. This creates a draft that pulls the air and exhaust gasses for venting. It also prevents the exhausted fumes from entering back into your home. Issues in the exhaust system can include cracking, leaking, and backdrafting. The cracks and leaks will allow the dangerous fumes, that should be funneled out of your home, to seep into your home. This is no different than a cracked heat exchanger and should be taken very seriously. Backdrafting, is when you have negative pressure in your home and the fumes are sucked back inside rather than removed. Again, this is just as dangerous as the scenario above. Having a maintenance technician inspect this component is crucial to your safety and proper system performance.
Measure supply/return temperature differential – You should see a temperature difference of 18-25 degrees between your air duct (or supply) and the return air. The supply is the air that is being pushed into your home and the return is the air that is being vacuumed back into your system for heating. If it is within this range your furnace is heating your home properly. If it is not in this range, there could be a number of reasons that your system isn’t getting your home to the desired temperature. A few reasons may include your ducting, clogged filter, faulty thermostat, debris in exhaust/intake vents and/or clogged drain lines. We recommend that a professional technician check your system since this can be quite dangerous and any mistakes could be quite costly.
Safety and control circuits – Checking for safety switches is extremely important to ensure that your furnace is not putting your family in any danger. There are 3 main safety mechanisms that are used. First, the pilot sensor is used to make sure the pilot light is on to ignite the burners. If for any reason, its off, this sensor automatically turns of the unit. This is important to stop gas from being pumped into your home with nothing to light it. Of course, a gas filled home is extremely dangerous. Second, the limit switch prevents the heat exchanger or “firebox” from overheating. This is where the carbon monoxide is being produced and when it overheats it can develop cracks which will leak “the silent killer” into your home. This is not only extremely dangerous, but very expensive to replace. Lastly, the roll out switch prevents a furnace flame roll out by shutting off the unit during this situation . When a furnace is turned on it emits a steady a flame within the combustion chamber. Under certain conditions, inflammable gasses can build up and remove the oxygen from the flames. When this happens, the flames grow larger until they receive the oxygen they need. This can cause parts of your furnace to heat up that aren’t built to handle high temperatures. This can cause expensive breakdowns and immensely reduce the heater’s overall lifespan. Also, this is extremely dangerous because it can cause nearby combustible materials to catch flames. In other words, this can cause a whole house fire and nobody wants that. During a routine maintenance, ensuring that these mechanisms are in working order saves lives.
Inspect and adjust fan belt tension – A furnace fan, one of the main components of the system, is responsible for moving heated air to where it’s needed. The fan is powered by the blower motor via a pulley belt. If this belt is damaged or loose it can slip off of it’s pulley track and cause the fan to make loud noises or completely stop working. This results in you getting significantly less heat than you’re paying for. When doing a routine maintenance, we ensure your belt is in tip top shape so not only do you save money on your utility bills and repairs, but so you also don’t have to deal with loud, uncomfortable noises.
Clean/replace air filter (If washable) – The filter is responsible to maintain good air quality in your home by blocking the dust and other contaminants that would normally be circulating throughout your home. Not replacing the filter on time will also cause your unit to work harder since its passage way is blocked by contaminants. This puts stress on all the moving components and it will immensely slow down the heating process in your home. This not only makes your home a lot less comfortable, but it will eventually lead to the breakdown of very expensive parts and even might cause you to need to replace your unit prematurely. If your filter is washable, we will wash it, dry it, and return it to your system making it like new. If you have a standard filter, we’ll replace it with a new one for free. This should be done every six months.
Lubricate and inspect blower motor air vents – The blower motor, responsible for forcing warm air through your home, usually needs a specific type of lubrication to upkeep its high performance and function overtime. If this is neglected, not only can it start making loud noises, but it can also cause costly breakdowns and more expensive energy bills. A technician will thoroughly check the blower
Furnace burner – A furnace burner is the component inside the heat exchanger where the air mixes with fuel, and is burned in order to make heat. The burner’s purpose it to heat up the looped coils in order to warm up the air that will pass into your home. Obviously, this makes the component absolutely crucial to the heating process. Without the burners working, there is not heat. However, the burners can still have issues and turn on at the same time. Meaning, the only way to catch these problems is by having your unit maintained. Some of these problems can include cracks, rust, clogs, and insufficient heat. The cracks, just like when a heat exchanger is cracked, can be very dangerous and cannot be repaired. The only solution for this is replacing the burners. Due to a lack of maintenance, furnaces can have poor air circulation and moisture build up which will cause rust to form on the burners, nobody wants that. This can either be cleaned off or replaced, depending on how much rust has accumulated. Not changing the furnace filter will cause clogs in the system and deteriorate the lighting capacity of the burners, this will cause decreased operation and loud noises. If this problem is caught on time, it can usually be fixed with a thorough cleaning. Lastly, if your heater just isn’t heating like it should, your burners may just need some adjustment. A technician should be called to do this as dealing with mechanical machines involving gas can be quite dangerous.
Heat exchangers – A heat exchanger is a set of tubes or coils that are repeatedly looped within your furnace for heating air. Simply put, this component is responsible for actually heating the air. Eventually, all heat exchangers fail. This is due to metal fatigue as it deals with very high temperature differences. When it gets really hot, the metal expands and when it cools off, the metal contracts. This is perfectly normal and part of the cycle for the heating process. Overtime, this expanding and contracting has the same effect on a heat exchanger that bending a paper clip and back forth has, it breaks. When that happens, the furnace is no longer safe to use and this component must be replaced. Heat exchangers should last between 10-20 years, but there are some factors that can shorten this lifespan. Mainly, a lack of maintenance on the system and/or poor initial system installation/design will cause the component to give out prematurely. A routine maintenance check up is absolutely vital to your heat exchanger’s safe operation and lifespan.
Inspect furnace exterior – In order to ensure there are no leaks coming in our out of the furnace, it is imperative that the exterior of the unit is completely sealed. If it is not, not only will the combustion gasses/carbon monoxide enter your home, but also contaminants from your attic or where your furnace is placed will enter your system and cause dirt and debris to accumulate and cause damages to your furnace. During a maintenance, the technician will thoroughly check the exterior of your system
Lubricate all moving parts per manufacturer specifications – Throughout the furnace, there are many moving parts. Since these parts are mostly made out of metal, they need to be lubricated. If not, the friction caused by all the moving parts will damage the equipment and greatly reduce its efficiency. If this is overlooked for long enough, the unit will need many costly repairs or an extremely premature need for replacement. Staying on top of your equipment will make your unit last 2-3x what it would without maintenance.
Blower Motor – Just like your air conditioning system’s blower motor, the blower motor in the furnace is responsible to circulate the air through your house and the heating system. Overtime, blower motors collect dust and tend to get quite dirty. Since, the blower motor is a spinning wheel the accumulation of dirt will cause it to shake and lose its balance. This reduces the airflow capacity and can cause it to breakdown resulting in costly repairs. In order to prevent this from happening, we ensure there is good filtration and that the blower motor is thoroughly cleaned.
Electrical Wiring – All the electrical wires across the system need to be connected properly and tight. Loose connections can cause the system to overheat and lead to failure. JMS will check that the connections are tight and stable to keep your system running smoothly and prevent these costly breakdowns.
Natural Gas – Ensuring there is a proper flow of natural gas to the burners is absolutely crucial to the heating process. The flame is supposed to be steady and have the proper of mixture of blue and orange (much more blue than orange). If the flame is too orange and unsteady there is too much oxygen and therefore, not enough pressure. If this happens, the system will either shut off due to its safety switches or it will short-cycle. Short cycling is when the system turns on for a little while then turns off and keeps repeating this process. During a maintenance, checking the pressure of natural gas will ensure your system heats when you need it to.