Furnaces tend to be out of sight and out of mind until they have a problem. Many furnace issues are avoidable, but you must be proactive to keep them functioning at their best. The right combination of a good HVAC maintenance schedule and a few essential HVAC choices will make all the difference.
Filtration
Filtration is process by which the air in your furnace remains clean. Understanding how to keep this air clean is essential.
Filter Replacements
Regularly replacing your furnace filters is easily the low-hanging fruit when it comes to avoiding problems. In many households, the built-in furnace filter is a fiberglass design that captures large particulate matter. These tend to be cheap and readily available at hardware supply stores across the country. Most furnaces also offer easy access so that homeowners can replace the filters.
A good replacement schedule is once every three months. However, you should check the filter monthly to see how well it’s holding up. In households with indoor air quality concerns, such as those with pets or allergy sufferers, owners may need to replace the furnace filter as frequently as once a month.
Clean Air Solutions
Air purifiers are a great addition to any home, particularly benefiting people with respiratory conditions. Your furnace will also benefit significantly from improved air filtration. Secondary systems tend to attach along the cold-air return, limiting their influence on the furnace’s intake pressure.
Added filtration benefits your furnace by providing clean air. The standard furnace filter has a MERV value of somewhere between 1 and 8. This means they capture large particles, like dust bunnies and bigger bits of dander. Such filters won’t capture finer particles. A purifier using a HEPA filter with a good MERV rating can significantly reduce the amount of dust that gets into a furnace. The results are improved efficiency and a longer system life for the furnace.
Poor Heat Production
Your furnace can run, although it may not produce the heat you need to stay comfortable. Here are some issues that can cause this.
Fan-Only Operation
Most furnaces have a switch that allows you to force it into fan-only operation. This is good for testing the furnace or providing some airflow during the summer. Unfortunately, folks often forget to switch the furnace back to normal operation, so check the switch each fall.
Thermostat Issues
In some cases, the furnace may not be the problem at all. A malfunctioning or poorly calibrated thermostat might not send the signal at the right time to the furnace. Many thermostats drift out of spec as they age, potentially leading to deviations from the set temperature by as much as 5°F. Our technicians typically recalibrate the thermostat as part of a home’s annual fall HVAC inspection.
Heat Exchanger Problems
The heat exchanger handles the transfer of warmth from the furnace’s combustion chamber to your home’s vents. It prevents exhaust and gas leftover due to burning from getting into your vents. A heat exchanger can suffer cracks from heating and expansion that can limit its efficiency. Likewise, a heat exchanger can corrode or collect carbon. We always check the heat exchanger and perform necessary maintenance with our annual inspections.
Clogged Burners
Combustion leaves carbon behind on surfaces inside your furnace. The place where most of the carbon collects is in and near the burners. Over the years, carbon can accumulate and lower burner efficiency. In the worst cases, clogged burners may prevent all of the gas from igniting, leading to dangerous gas accumulation in your system. Many homeowners notice this in the form of loud ignitions when the accumulated gas hits flames from burners that are still lighting properly.
Electrical Issues
A furnace may also develop electrical problems. The control board might be shorted, preventing the furnace from working at all. Capacitors can also overheat or fail, potentially inhibiting or ending furnace operation. Wires for signals and power can also corrode. Overloads sometimes happen that force the breaker to trip, too.
Weak or Stopped Pilot Light
A weakened or stopped pilot light can cause the safety system to prevent the furnace from coming on at all. Pilot lights may fail for many reasons. Once more, cleaning carbon accumulation on the light and thermocouple or flame sensor can ensure a proper signal. It is also wise to check for any leaks along the gas line to the pilot light.
Short Cycling
Short cycles usually happen because a safety shutoff in the furnace triggers. For example, poor airflow can cause the burners to heat up too quickly, resulting in the safety systems shutting the furnace off. Make sure your furnace gets the airflow it needs. Remove any obstructions near air vents and return registers. Also, make sure the intake and exhaust systems are clear of obstructions.
Noises
Multiple issues in a furnace can cause noises. The solutions tend to vary based on the sources.
Squealing
The blower motor is responsible for nearly all squealing sounds in a furnace. Lubricating the blower motor’s components, especially the belt, is typically the best way to resolve the issue. Lubrication is a standard part of our inspection checklist.
Vibrations
Moving parts loosening can trigger vibrations. Fans and blower motors are the most likely culprits. Lubrication may be the solution, but replacement is also a common solution.
Water Accumulation
Homeowners are often surprised to see water accumulating near their furnace. Especially with high-efficiency systems, removing condensation from the air before heating it is critical. The removed condensation then has to go down a drain. If this drain clogs, water can back up. Given that a high-efficiency furnace can generate as much as three gallons of condensation per day during peak season, a backup can pool quickly. We can flush the drain and treat it to knock out most clogs.
Smells
The air coming out of the vents from a furnace should have little to no smell. Clean air is always the goal.
Mustiness
If there’s a musty smell, the heating system may require cleaning because mold is accumulating. You may also want to look at whether your basement or service closet is staying dry enough. Dehumidifying a basement prevents musty air from getting into the furnace, potentially eliminating musty odors. An air purifier may also help.
Gas
Gas smells are always a red flag. The smell of gas should never make it from your furnace to the living area. If gas is accumulating enough for you to notice it even slightly, shut off the furnace and call us immediately. If there is a strong smell of gas, consider leaving the house entirely and then contacting us and your gas company.
Annual Inspection
An annual inspection is the best way to avoid the most common furnace problems. Our technicians can check all the systems related to common issues and address anything they find. Not only does this prevent problems, but it improves the odds that you’ll get a few more years out of your furnace. Likewise, your furnace is likely to use less energy, saving you money.
Fox Heating, Cooling & Plumbing serves Wheat Ridge, CO and other areas with heating services in the Denver metro area. We have been in business for more than 20 years. Commercial and residential customers are welcome to talk with us about HVAC issues. Our company is locally run, and we take pride in keeping our neighbors’ homes comfortable.
If you’re concerned about an issue with the furnace in your Wheat Ridge home or business, contact Fox Heating, Cooling & Plumbing today.
