Furnace failure rarely occurs out of the blue. In many cases, a total failure only occurs after you have ignored some problems. Below are some of the telltale signs that should tell you a furnace is headed for disaster and requires quick intervention.
You should diagnose your furnace if it is no longer starting as easily as it used to do. Several things can affect a furnace's ease of starting. Maybe the thermostat is malfunctioning, the start capacitor is malfunctioning, or the air filter is blocked, among other problems. Whatever the problem is, you need to figure it out fast and correct it before the furnace completely fails to start.
Increased Dust Levels
In addition to heating up the indoor air, the furnace should also remove particles from the air so that you can breathe in clean air. The air filter is the part of the furnace responsible for cleaning the air. Unfortunately, your air filter might not do its job properly if it is of the wrong size, is dirty, or if the furnace is undersized for your house. What is more, increased dust in the house is not just bad for your respiratory system; it can also affect the furnace because a dirty furnace tends to overheat and struggle at its job.
You should also suspect a heating problem in the offing if your furnace is noisier than usual. Furnace fan malfunction, delayed starting, damaged bearing, motor malfunction, and even air duct leakages are all possible causes of furnace noise. Unfortunately, all these noises can trigger impaired heating for your furnace.
A short-cycling furnace is one that is switching between "on" and "off" cycles too frequently. Short cycling overexerts the furnace, increases wear and tear, and can lead to furnace breakdowns. Typical causes of short cycling include improper furnace sizing, thermostat problems, overheating, and even dirty air filters. You risk further damage to the furnace, and impaired heating if you don't diagnose and fix the issue.
Discolored Pilot Light
In traditional (older) furnaces, the pilot light provides the heat that ignites the gases to trigger combustion and heating. Ordinarily, the pilot light should be yellow with a bluish tip. A completely blue pilot light means overheating and a completely yellow pilot light means under heating. Typical causes include improper adjustment or impairment of the pilot light system. Both problems can lead to impaired heating if you don't correct them in time.
Reach out to a heating repair service if you suspect your heating system needs attention.