Q2: Why does my 4xxx unit make a buzzing sound when powered by AC voltage? Answer: Certain classes of ceramic capacitors exhibit a normal characteristic, called piezoelectricity. In some cases, an acoustic sound may be heard, coming from the capacitor itself. Ceramic piezo effects are well known, and were even the basis for the ceramic phono cartridges used in the past. This is a normal characteristic of the capacitors used in the 4xxx modules, and has no affect on reliability or accuracy of the unit. PR electronics' multifunctional transmitters offer versatile devices for isolation, conversion, scaling, amplification, alarming, control and more.When it comes to electricity and wires, people are skittish. So when you start to hear buzzing/humming noises coming from your circuit breaker panel (aka, the main electrical panel), you’re afraid to even open it for fear of being electrocuted (as you should be). And the noise itself is probably driving you nuts at night!

In this article, we’ll cover the 3 main reasons your electric panel is making this buzzing/humming noise when your air conditioner is running.lennox air conditioning unit problems Do you want immediate professional help and live in the Phoenix metro area? trane ac unit green light flashingAsk one of our experts for help.carrier split system air conditioner wiring diagram First, we want to possibly ease your concerns. If the humming or buzzing isn’t very loud, this is normal. Energy comes in and out of the panel at a rapid pace and this creates vibrations in the breaker that you can hear coming from inside the panel. But if the buzzing or humming is very loud, keep reading. Here are a few reasons as to why:

A circuit breaker’s job is to protect your family by cutting power to an electrical device when the current flow gets too high. For an air conditioner, a circuit usually trips when the A/C overheats. But when a circuit breaker goes bad, it can fail to trip when it’s overloaded. This could be causing the buzzing noise when the A/C runs because the breaker is taking in a large load but can’t trip like normal. That’s bad news because it could eventually lead to a fire. You’ll need to get a professional to replace the circuit breaker if this turns out to be the issue. If a wire connected to a circuit breaker isn’t connected securely (or it’s damaged), it can cause a buzzing noise (and create some sparks, too). Just like the bad breaker, this is dangerous and needs a professional’s attention ASAP. If you live in the Phoenix metro area and have a loud buzzing/humming noise at your circuit breaker panel, we can help.Loud buzzing noise from an AC unit indicates stress on a HVAC system, specifically an electric issue.  

It is important that you do not become familiar with the noise, and instead turn off your AC unit and call a licensed HVAC contractor. It is also important to distinguish the noise from rattling or grinding, as those sounds are a typically signs of malfunctioning parts, debris or misalignment.ElectricalBuzzing noises are usually from electrical arcing – a discharge when electricity is jumping between circuitry. Loud buzzing noises indicate the electrical voltage flowing through your air conditioner is not at its correct amperage. Failing electrical components increases the risk of fire and should be diagnosed by a licenses HVAC expert to keep you and your home safe.MotorThe motor needs to be lubricated with oil, especially in older AC units to keep bearings from getting worn and eventually malfunctioning. A bent blade on the fan could also cause a buzzing noise. Lubricating the motor or replacing fan blades should be done before extensive use of AC (at the beginning of summer for example) to prevent a malfunctioning system later on.

RefrigerantIf a buzzing or hissing noise is coming from the AC unit itself, it could be a sign of a refrigerant leak. Refrigerant leaks cause AC units often freeze up, even during the hottest time of year when the AC is consistently on. Water dripping onto the motor will cause also an abnormal noise; the repair would involve locating the obstruction/leak and properly isolating the unit.PartsThis is associated more with a rattling noise, but misalignment or loose screws/panels could also create a ‘buzzing’ noise. Poor installation or aged AC parts cause screws to become loose also causing the panels on the cabinet to unfasten. At Action Air Conditioning, Heating & Solar we care about your comfort and savings. We guarantee convenient and efficient service for all maintenance and repair calls. Did you know 90% of all HVAC breakdowns are caused by lack of maintenance?  Don’t put your comfort on hold, Call or Schedule Your Maintenance or Repair Appointment Today! Funny air conditioner sounds should be inspected by a professional.

The outside unit of your central air conditioning system is called the condenser. This unit compresses refrigerant and discharges the heat your system absorbs from inside your home. It’s normal to hear noise from your air conditioner’s condenser unit when it's running; however, not all noises are harmless. If your condenser unit is making funny or unusual noises, it may be an indication of a serious problem that should be addressed by a certified HVAC technician. Turn off the power to your air conditioning system at the main breaker panel or fuse box. Inspect the fasteners on the metal cage surrounding your condenser unit if you hear rattling during operation. Tighten the screws or bolts that hold the cage in place to stop the noise, using a screwdriver or an adjustable wrench. Contact a certified HVAC technician if tightening the bolts doesn’t quiet the rattle. The compressor motor mounts may have failed, which causes the motor to rattle around inside. Sweep debris off the top of the unit, using a broom.

Move any objects leaning against the sides or base if you hear thumps, bangs or thuds during operation. Inspect the fan blades if you hear clicking or ticking noises. If a blade is bent, this can cause it to wobble, which can produce these sounds. Contact a technician to replace or repair the blade. Look for loose wiring or signs of burning near the wire connections if you hear buzzes or hums. If you see signs of burning, leave the system turned off and contact a technician for service as these are an indication of an electrical issue or a failing motor. If your unit makes a humming noise but doesn’t start, this indicates the compressor motor may have seized or the system may not be running at the proper voltage. All of these problems should be repaired by a professional. Call a certified HVAC technician immediately if the condenser unit is making loud screaming, hissing or whistling noises. Loud hissing or high-pitched whistles indicate a possible refrigerant leak. Refrigerant gas can be extremely dangerous, even in small quantities.