Electrical System Noise Sources

Find & fix noises traced to building electrical components, wiring, devices

Building noise traced to electrical system components, fixtures, devices, transformers, relays, or wiring.

How to track down and fix building sounds originating in electrical system components or devices.

We also discuss methods of sound or noise control in buildings during construction or as a building retrofit.

Electrical Equipment or Electrical System Noises in buildings: diagnosis & cure

List of Common Sources of Noise from Electrical Sources

Our photo shows a battery-backup power supply used to protect computer equipment from power surges and from brief electrical power outages.

You might hear a periodic beep if the system has switched to battery backup, but some battery backup systems also make regular clicking noises or may even include a small fan that those with acute hearing can notice.

It is important when tracking down sounds coming from electrical panels, wires, or equipment to decide quickly if the noise is normal or if it indicates an unsafe or abnormal condition .

Watch out: Electrical System Noises can be signs of dangerous conditions: buzzing circuit breakers or fixtures may indicate that an electrical circuit is short circuiting or that a circuit breaker is not tripping when it should.

The risk is fire or electrical shock. If a circuit is acting strangely with flickering lights, noises, or odors, turn it off at the main electrical panel and call a licensed electrician promptly.

If you are unable to safely turn off an electrical circuit for any reason, get people out of the building and call your fire department or emergency services.

• Air conditioner compressor motors or fan motors 
  
  that are damaged, unable to start, or may be suffering from low voltage or a bad start capacitor may hum without starting.
  
  Watch out: Shut off electrical motors that hum without starting to avoid overheating, further damage, and a possible electrical fire.
  
  See AIR CONDITIONING & HEAT PUMP NOISES for a list of sounds coming from those systems
  
  For heat pump or air conditioner compressor motors that hum
  
  see HUMMING SOUNDS from A/C sounds from A/C or Heat Pump system


• ALUMINUM WIRING HAZARDS - include a building fire risk that may be indicated by
  
  flickering lights, circuits that do not turn off or on, hissing crackling sounds, burning plastic odors.
  
  Watch out: turn off electrical circuits that are flickering or making noise and obtain help from a licensed electrician
• APPLIANCE NOISE DIAGNOSIS -
  
  appliances, such as air conditioners, cookstoves, ovens, water heaters, even toasters and microwaves each have their own collection of normal noises but also some other sounds that can indicate trouble.
• Buzzing sounds at circuit breakers, receptacles, lights or other electrical components may be unsafe
  
  (also crackling) at electrical components anywhere, including compressor relay switches, electrical connections at any component, and quite seriously, at circuit breakers can be an indication of arcing and an electrical problem needing prompt attention.
  
  Watch out: Turn off such circuits immediately and contact a professional electrician or service technician.
  
  Also see FEDERAL PACIFIC FPE HAZARDS
  
  and ZINSCO / SYLVANIA HAZARDS
• Clicking or chattering noises
  
  Clicking or chattering at an HVAC equipment control such as a control relay can tell us that a heating or air conditioning or other electrical system controlled by a relay switch is failing.
  
  See CHATTERING RELAY CONTROL SWITCHES as buzzing and chattering can be confounded.
  
  see HVAC CLICKING SOUNDS from air conditioner or heat pump system equipment.
  
  Other clicking and ticking noises at an electric heater might simply be normal thermal expansion or contraction as the device heats or cools.
  
  See TEMPERATURE CHANGE RELATED NOISES 
  

• ELECTRIC METERS & METER BASES
  
  of older designs sporting a rotating metal disc may produce a whirring sound when the meter is spinning.
  
  At a Poughkeepsie New York home we asked the local electric meter reader about the noisy meter on a house. He gave the meter a solid smack!
  
  The noise stopped. For a time.
  
  Really? Well that's what he did but we don't recommend this repair approach, though indeed sometimes mechanically disturbing a noisy part is diagnostic.
• Electronic equipment noises -
  
  clicks (typically relays), ticks, and whirs (typically fan noises), and occasional snap-click sounds (hard drive or disk accessing) are noticed by people with acute hearing.
  
  Our photo (above left) shows a backup computer equipment power supply that contains a battery, switching equipment, and electric power conditioning circuitry. We expected it to be silent, but in fact in a quiet room one can hear a periodic clicking from an internal relay in the device.
• Electric Motor noises -
  
  include normal operating hums and louder noises when a motor bearing is failing, a pump is running dry, or the motor shaft is binding. You may hear buzzing from motor vibration or even shrieking or groaning from a failing electric motor bearing.
  
  See ELECTRIC MOTOR NOISE DIAGNOSIS for a full list of diagnostic checks for noisy electric motors.
• Hissing, Humming, Frying, Zapping electrical noises:
  
  humming from a transformer (may be "normal) mounted nearby, but hissing, zapping, frying sounds at the electrical panel or at electrical switches and receptacles is a sign of burning, short circuits or other unsafe conditions.
  
  Watch out: Turn off such circuits immediately and contact a professional electrician or service technician.
  
  

  See the electric motor diagnosis and repair steps for humming or buzzing electric motors at

  ELECTRIC MOTOR WON'T START / RUN 

• ELECTRICAL SYSTEM INSPECTION
  
  for home buyers provides guidance in identifying and fixing electrical hazards in homes: aluminum wiring, Federal Pacific FPE Stab-Lok panels, mis-wired circuits, fire and shock hazards
• FAN NOISES in BUILDINGS -
  
  fan noises including fan motor noise and air movement noises
• FEDERAL PACIFIC FPE HAZARDS -
  
  flickering lights, circuits that do not turn off or on, hissing crackling sounds, burning plastic odors
• ELECTRIC POWER LOSS / FLICKERING LIGHTS-
  
  causes of flickering or dimming lights
• HEAT, ELECTRIC -
  
  clicks or creaks as an electric baseboard heats up are normal. But hissing, buzzing, crackling, snapping may be an electrical short and are dangerous. Heating system noises involving electrical components may be traced to motors, relays, switches, transformers and wiring.
• LOW VOLTAGE BUILDING WIRING -
  
  may include low humming noises at failing voltage transformers
• OIL BURNER NOISE SMOKE ODORS
  
  describes other sources of noisy oil burner motors & assemblies.
• PUSHMATIC - BULLDOG PANELS -
  
  flickering lights, circuits that do not turn off or on, hissing crackling sounds, burning plastic odors
• RUST in ELECTRICAL PANELS -
  
  flickering lights, circuits that do not turn off or on, hissing crackling sounds, burning plastic odors
• SQUARE-D COUNTERFEIT BREAKER RECALL -
  
  flickering lights, circuits that do not turn off or on, hissing crackling sounds, burning plastic odors
• Transformer buzzing:
  
  low voltage transformers power building components such as doorbells and heating or air conditioning controls. A failing transformer may buzz.
  
  See LOW VOLTAGE TRANSFORMER TEST
• ZINSCO / SYLVANIA HAZARDS -
  
  flickering lights, circuits that do not turn off or on, hissing crackling sounds, burning plastic odors

...

Reader Q&A - also see RECOMMENDED ARTICLES & FAQs

What is causing constant buzzing noise on this electrical device? Traced to Fire Alarm

This has been buzzing constantly for months, and the building manager won’t reply. What is this?

I am from Canada British Columbia. In an apartment? I figured out it’s from the closet. I just pressed reset and the sound went off…do you know what this is? On 2022-12-05 by A bee

by InspectApedia (Editor)

@A bee,

I don't know we're looking at as we have not one bit of context. What is the country and city of location, what kind of building is this, where in the building is it located, and can you get a sharper photo that shows any text or writing on that plastic cover.

If there are screws you could also remove the cover and look to see what's inside and post a photo of that and we are likely to be able to tell you what it is.

Watch out: if this is an electrical device that's having a short circuit it could be a fire hazard, something that's worth mentioning to your building management.

Clearly that's a control panel for something, perhaps an air conditioner or venting system, currently not initialized as the display shows odd figures.

What is the embossed writing that is on the cover in your prior photo - it's a bit blurry so we couldn't make it out.

If you can identify a manufacturer or product name anywhere on the system that will help track down what the control is intended to operate.

by A bee

@InspectApedia (Editor), the control is in the Closet and the other thing is a fire alarm and it’s in the front. Do you think they’re connected? Sorry I didn’t send the other pic, I wasn’t sure if they were connected anymore. This is the one outside the closet:

by InspectApedia (Editor) - Buzzing noise at Mircom Fire Alarm system device

@A bee,

+OK that's an image I can read: that's a Mircom Fire Alarm system device.

Mircom's website makes it difficult to find company contact information but you can post an inquiry at

https://mircom.com/product-documents/#contact-us

to ask their help in identifying the model of your Mircom fire alarm system and then they can provide you with an owner's / installer's manual for that specific Mircom fire alarm system product.

Mircom sells wireless (and probably also wired) building management systems beyond fire alarms, such as "building automation systems" , emergency exit lighting, integrated fire detection and building communication systems, access control systems,

Contact Mircom:
CORPORATE/CANADA
Tel: 888.660.4655
Fax: 888.660.4113

USA
Tel: 888.660.4655
Fax: 888.660.4113

INTERNATIONAL
Tel: 905.660.4655
Fax: 905.660.4113

mircom.com

...

Continue reading at ELECTRIC MOTOR NOISE DIAGNOSIS or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

Or see ELECTRICAL SYSTEM NOISE FAQs - questions & answers posted originally at the end of this page.

Or see these related

Recommended Articles

• BUZZING NOISE DIAGNOSIS - topic home
• ELECTRICAL CIRCUITS, SHORTS
• ELECTRIC MOTOR NOISE DIAGNOSIS
• ELECTRICAL SYSTEM NOISES
• HUMMING NOISES in BUILDINGS - topic home
• NOISE / SOUND DIAGNOSIS & CURE - home
• SOUND CONTROL in BUILDINGS - managing to damp down normal noises from electrical equipment

Suggested citation for this web page

ELECTRICAL SYSTEM NOISES at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.

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INDEX to RELATED ARTICLES: ARTICLE INDEX to BUILDING NOISE DIAGNOSIS

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