Why is my AC making a humming sound?

 HVAC Contractor | HVAC Repair Redwood City

Never Neglect a Noisy AC Unit

It is no longer the norm not to have an air conditioning system in your home. Air conditioning systems are no longer considered a luxury but rather a need. Your air conditioner has the potential to improve your house, health, and general well-being. It can perform more than you can think if properly maintained.

Heating and Cooling Company in Redwood City | HVAC Repair Redwood City

Depending on the kind of air conditioner you have at home, modern HVAC systems utilize sound-dampening technology to keep the sound level between twenty-five and fifty-five decibels. In layman’s terms, twenty-five decibels is equivalent to a whisper, while fifty-five decibels is equivalent to a common mid-level discussion at home. The most recent window and mini-split ductless air conditioners are quieter than central ducted units. Any AC that is generating unusually loud and unexpected noises is most likely aggravated by a malfunction or a condition that requires you to look for a competent HVAC company in Redwood City. Although bothersome, air conditioner noises can lead you to a problem before it becomes unfixable or prohibitively expensive to repair, such as fixing a fan motor or a compressor.

Because multiple disorders can sometimes generate the same sort of noise, it is important to know what the various noises could imply. With this, you can also easily hire an expert when it comes to HVAC repair, installation, and maintenance for you to get rid of a noisy cooling system and prevent it from becoming fully dysfunctional.

7 Common Causes Why Your AC is Humming

Modern air conditioners are quieter compared to their predecessors. And we’re pretty sure that you want your unit to stay quiet as much as possible. But don’t worry because you are not alone when your HVAC unit is making a humming noise. As a matter of fact, a humming sound is usually the most common noise you can hear, and sometimes, the hum noise level is more intense depending on the brand of the air conditioner you have.

A humming noise usually indicates the steady drive of the outside fan and motor. On the other hand, a loud humming sound could also indicate a mechanical or electrical issue with your AC. 

Here are seven (7) most common causes why your AC hums:

  1. The unit’s condenser fan motor may be unable to spin but still receive enough electricity, resulting in resistance and a noticeable—and frequently loud—humming sound.
  1. The contractor relay switch is mechanically and electrically faulty. The contractor relay switch is responsible for activating the outside unit when the inside temperature increases to the level where cooling is required. A humming sound might be produced when the contractor breaks. To check or troubleshoot the problem, the switch is located outside your home in the outside condenser unit.
  1. The circuit breaker might be overloaded. Generally, when a circuit breaker is overloaded, it trips. If the circuit breaker is malfunctioning and will not reset, you may hear an electrical humming noise.
  1. The condenser has ice on it. If your air conditioning unit freezes, you may hear a loud humming noise. When your AC is frozen, other possible causes include a refrigerant leak, a blocked air filter, or a damaged blower motor. A faulty blower motor in your furnace can occasionally make a humming noise. If the furnace is located near the external condenser, the source of the humming sounds might be misidentified. Check to determine whether the buzzing is greater near the external condenser unit or the furnace when the air conditioner is turned on.
  1. The condenser fan motor of your air conditioning unit is damaged. A broken condenser fan motor, like a failed blower motor, can produce a buzzing noise when it fails. Your fan motor may make a loud noise if the indoor blower is on, but the fan is not rotating. Some individuals describe this noise as a hum rather than a buzz. This component can fail for a variety of reasons, including debris entering the condenser, overgrowth surrounding the unit, and loose parts.
  1. Loose components inside your AC unit. Your HVAC system is a complex machine with many moving parts. It’s likely that a few pieces become loose over time due to normal wear and tear. A loose component can lead to premature wear and loud sounds, such as humming.
  1. The refrigerant pipes are vibrating. Vibration can occur if the refrigerant lines are undercharged. This vibration will occasionally sound like a hum. Other reasons for a vibrating refrigerant line include a poorly installed expansion valve.

A humming sound indicates that something inside your air conditioner is malfunctioning and should be checked immediately. Given the aforementioned factors, determining the source of the sound is beneficial. Your complete HVAC system functions as a single unit. To function properly, the air conditioner requires appropriate ventilation. The air filter filters the air, and the blower motor (found inside the furnace) propels the air through the whole system to heat or cool your home. If the air filter becomes clogged or the blower motor fails, it might cause problems with your outdoor condenser unit.

Resolving the AC humming problem is best accomplished by having a professional do a diagnostic examination on your entire unit. Only a skilled expert should do this work, not a homeowner. If you should replace your unit, we provide inexpensive solutions with top-tier repair services that can help you save a bunch of money.

HVAC Repair | HVAC Repair Redwood City

Reasons Why Your AC Unit Makes a Humming Sound

A humming sound coming from your cooling unit is normal. However, when the humming noise is intensively loud, a necessary diagnosis on your unit should take place immediately to see where the noise is coming from. Here are the most common reasons why your AC is humming:

  1. Malfunctioning condenser fan motor. There might be times that a condenser fan might not work properly and thrive to spin, causing your AC unit to produce a humming sound.
  1. Mechanical or electrical malfunctions. The contractor relay switch in your AC is responsible for starting the outside unit when the indoor temperature increases. When this switch breaks down, it produces a humming sound.
  1. Overloaded circuit breaker. When the circuit breaker is overloaded, it trips. When this happens, an electrical humming noise may arise.
  1. Frozen condenser. A frozen condenser is one of the most common reasons why your AC unit hums. When this happens, a blower motor might break down, and when the blower motor breaks down, it will create a humming noise.
  1. Damaged condenser fan motor. When a condenser fan motor fails, it might make a humming noise similar to a failed blower motor. If the indoor blower is turned on, but the fan is not rotating, your fan motor may create a loud noise.
  1. Loose components. A loose component can cause early wear and loud noises like humming.
  1. Vibrating refrigerant pipes. If the refrigerant lines are undercharged, vibration might develop. This vibration will sometimes sound like a hum. A poorly placed expansion valve is another cause of a noisy refrigerant line.

We have inexpensive services here that could help you save your HVAC unit from becoming entirely inoperable. All you need to do is call us at your most convenient time for faster and stress-free booking assistance.v