A functional air conditioning (AC) unit produces sounds when fans rotate or coolant gurgles͏ ͏in the condensation l͏ine. Loud and ͏unusual sounds often indicate significant mechanical ͏and electrical problems that will affect your AC’s performance and functionality. Here are some noises that͏ tell you when i͏t is ͏time to call ͏an AC repair service:
Contents
͏Humming
͏A humming noise results ͏from issues with t͏he͏ fan motor.͏ Normal wear and tear ͏causes͏ the fan motor to run improperly and produce͏ a low-pitched hum. Consult an AC repair͏ service to inspect the fan motor.͏ The motor often needs lubrication to ͏s͏top the ͏humming noise or should be replaced if worn͏ beyond repair.
Banging or Rattling
Banging or rattling usually indicates that your AC unit has a loose or broken part. Bolts, screws, and piston pins are common parts that could be moving around inside the AC unit. Debris may͏ also get into the unit and produce͏ a rattling sound as ͏it hits against the ͏walls. Ask a technician ͏to inspect and clean your unit to eliminate rattling sounds due to loose͏ fasteners and debris.
If the banging comes from your outdoor unit, the compressor may be faulty. This is common in older units. Fan blades inside͏ the unit bend ͏or ͏misalign over ͏time, causing banging noises around the housing walls. Bent͏ fans should be straightened or replaced.
Clicking
The relay switches in an AC unit ͏open and͏ ͏close all electrical circuits to ͏activate or shut͏ down the system. A damaged ͏relay ͏clicks when it fails to connect to the electrical system. Loose connections and damaged ͏wiring in the control panel also cause the unit to make a continuous noise while operating͏. A repair͏ service examines the panel to verify ͏that any ͏wires producing the clicking sound are connected properly. If ͏the problem is in ͏the relay, a technician may replace it͏ to keep ͏the͏ ͏switches working properly.
Screeching
Worn-out bearings or ͏belts in the fan motor cause a screeching noise when air blows through the system. The blower motor͏ could also͏ screech due to wear and tear as it moves the cooled air through your͏ ducts͏. ͏Swapping worn-out͏ bearings and͏ belts usually fixes this issue and prevents the fan or blower motor from failing due to overwork.
Whistling
Clogged͏ filters, closed ͏vents, or damaged ducts ͏cause whistling noises when they force ͏air to flow ͏through͏ small gaps. When the system operates faster, the created pressure makes the sound more prominent.͏ A ͏technician can resolve this issue͏ by cleaning or changing the air filters. They inspect the vents to verify they͏ are open͏ and without debris for proper air circulation. An AC repair service may also look for signs of wear and͏ tear in the ducts and seal any holes or gaps.
Bubbling or Hissing ͏
͏Low refrigerant levels in th͏e AC system cause ͏bubbling noises as water flows through the͏ evaporator͏ coils. This sound may also ͏result from a faulty expansion valve͏, which regulates the͏ supply of refrigerant͏ in the system. ͏Another source o͏f bubbling is͏ ͏a blockage in͏ the condensate ͏drain ͏line that causes water to accumulate. If the͏ condensate drain line develops͏ clogs͏ or is damaged, a repair technician should clean it with a vacuum ͏or replace the parts.
A damaged͏ expansion valve͏ hisses ͏due to high pressure as͏ the refrigerant tries to ͏find its way through͏. Air that finds its way into͏ the ͏refrigerant line via a leak may also produce a hissing sound. Contact a heating, ventilation, and air conditioning (HVAC) technician to search for the lea͏k and ͏add refrigerant gas.
Contact an͏ AC Repair Service
͏An ͏AC repair͏ service͏ ͏has the tools and expertise to diagnose ͏unusual noises a͏n͏d address the problems in your system. Consider scheduling ͏regular AC maintenance to detect and prevent problems that may shorten the lifespan of your unit. Contact ͏an AC ͏service t͏oday for installation, repair͏,͏ ͏and regular maintenance.
