Furnaces are one of the most popular heating systems on the market today. This is due to their relative affordability and versatile fuel options. Unfortunately, no matter what type of furnace you have, it’s likely that you’ll need to call for furnace repair service at one point or another. Here are some of the causes.
Not Producing Heat
One of the more irritating issues you may experience is that your furnace isn’t blowing hot air. If you have already checked to ensure that your thermostat is set correctly and that your air filter isn’t dirty, there’s likely a problem with the igniter for your furnace.
Most modern furnaces have an electric igniter that sends a spark to the burner to start burning the fuel supply to your furnace. Older models rely on a pilot light to ignite the burner. If the pilot light goes out or the electric igniter malfunctions, your furnace won’t be able to produce heat.
Another culprit behind why you may not be getting hot air out of your ductwork is a broken blower component. In this scenario, your furnace is going to run as normal. However, the blower components won’t be able to successfully move that heat to where you need it. In most cases, the issue is going to be a broken blower fan belt. In rarer instances, the issue may be a faulty blower motor.
Immediately Shutting Off
Another issue you may run into when you notice that your furnace isn’t producing heat is that it seems to turn on and then immediately shut off. You’ll want to watch the cycle to see if the igniter ignites your burner. In the event that the burner ignites but immediately shuts back off, there’s likely a malfunction with your flame sensor. A flame sensor is responsible for sensing when there is a flame in the burner. If it senses there’s a flame, it will allow fuel to flow through to the burner.
To prevent harmful fumes from backing up, however, it will shut off the fuel supply as a safety measure if it doesn’t sense a flame. If your system immediately shuts off, the flame sensor itself could be faulty and need to be replaced. In other cases, the sensor eye may simply be covered in soot and falsely sense that there’s no flame. Merely cleaning the sensor eye will usually return your system to functioning as it normally does.
Odd Noises
When your thermostat first signals to your furnace that it’s time to turn on, it will make a slight clicking noise, and you’ll then hear the whooshing of air traveling through your ductwork. However, if you start to hear other noises coming from your furnace, it’s a real cause for concern. Typically, the particular sound will give you some insight into what the problem may be.
For example, if your furnace starts to make a rattling noise, that typically indicates there’s a loose component somewhere inside the system. If you hear a grinding noise, it’s likely a problem with the blower motor. If you hear a fairly loud rumbling noise, it could indicate that there’s excess fuel left in the combustion chamber. All of these issues should be looked at by a professional sooner rather than later.
Odd-Colored Flame
When your furnace is running, the flame in its burner should always be blue. This indicates a healthy burning of your fuel. In the event that the flame takes on a different color, such as yellow or orange, it indicates an issue with your burner. In most cases, there may be excess debris blocking the fuel supply so that your burner can’t get up to the right temperature. In other cases, the burner itself may have too much buildup that is preventing adequate combustion of your fuel.
Blower Fan Running Non-Stop
Another issue you may run into is that your blower fan seems to be running non-stop. It’s best to first check the settings on your thermostat to ensure that you have it set on “Auto” instead of “On.” If your thermostat is set to “On,” the blower fan will constantly run until you change the settings. If your thermostat is set to “Auto,” then you may have a faulty limit switch. This switch is responsible for turning off your furnace whenever the air in your ducting reaches the set temperature on your thermostat.
Thermostat Not Working
One really frustrating issue you may experience is that your thermostat doesn’t seem to turn on. It’s best to start by checking your circuit breaker and the batteries inside the thermostat. If neither of these issues is the problem you’re experiencing, then there’s an issue with your thermostat itself or the wiring going to it.
Inadequate Heat
If you’re getting a slight amount of heat from your vents but it isn’t what you’re used to, it can indicate a problem with your furnace. The most obvious culprit is a dirty filter, and the problem can be remedied by simply replacing it. If that doesn’t solve the issue, there could be a blockage somewhere in your ductwork, a big air leak that has developed, or a faulty thermostat.
In cases of a blockage, you’ll get adequate heat out of all the vents that run before where the blockage is located. Only the vents after the blockage will experience inadequate heat. An HVAC technician will be able to assess your ductwork for any blockages or major air leaks. If the problem doesn’t lie with your ducting, your thermostat may have a faulty or miscalibrated thermometer that isn’t reading correctly.
Abnormal Smells
Another alarming issue you may experience with your furnace is that it’s producing an abnormal smell. The only time that your furnace should be producing a smell is when it first starts up for the season as it burns off excess dust. If you get a whiff of a musty odor, there’s likely mold or mildew inside your ductwork. If you get more of a metallic smell, it usually signals an electrical problem with one of your furnace components. A rotten egg smell means that you have a gas leak and need to shut off your gas supply.
Repeatedly Tripping the Circuit Breaker
It’s not uncommon for your furnace to trip a circuit breaker right after a nasty power outage. However, if you find that the circuit breaker keeps tripping, it’s important to discover the underlying culprit and repair it as soon as possible. Some of the most common reasons include a dirty air filter, blocked ductwork, blower motor problems, and a faulty circuit breaker.
Frequent Cycling
If you notice that your furnace seems to be kicking on more than a few times an hour, it’s over-cycling. This can happen due to a number of different issues like inadequate air flow, a clogged air filter, or having your thermostat set too high. It’s important to have a professional assess the root cause of the problem because frequent cycling can easily drive up your utility bills.
Trustworthy Furnace Repair Service
Our team at TCS Heating and Air Conditioning offers trustworthy furnace repair services to the New Britain, PA community. We can assist with all your heating, cooling, ductless mini-split, ductwork, boiler, HVAC zoning, and indoor air quality needs. Simply call us today to schedule your next furnace repair appointment.
