Maximize Efficiency and Comfort in Your Southern California Home

LA & Orange County AC Repair and New System Installation Experts

Coastline Mechanical Inc. stands as the leading C-20 licensed HVAC contractor catering to both Los Angeles and Orange Counties. We provide tailored, top-notch heating and air conditioning solutions that are built to endure the diverse Southern California climate. Our priority lies in optimizing your home's energy efficiency, guaranteeing system dependability, and providing enduring comfort throughout the year.

Before and after of a furnace. Old unit is rusty, new unit is white with a

Comprehensive HVAC Service

HVAC technician installing ductwork on a ceiling, wearing gloves and gray uniform, using a ladder in a modern office.

Residential & Commercial HVAC Repair

Don't let common heating or cooling issues disrupt your home or business. Our certified C-20 technician specialize in swift, effective solutions, leaving no mess to disrupt your daily life, allowing you to enjoy your space free from HVAC troubles.


  • No Cold Air: AC unit blowing warm air or not cooling at all, often due to refrigerant leaks or compressor failure.
  • No Heat: Furnace failing to ignite, pilot light issues, or heat pump malfunctions leaving your space cold.
  • Strange Noises: Banging, clanking, or hissing sounds from your AC or furnace indicating mechanical problems.
  • Poor Airflow: Weak air coming from vents, signaling dirty filters, blocked ducts, or fan motor issues.



Common HVAC Problems We Fix

HVAC technician inspecting ductwork with a flashlight in a mechanical room, wearing a gray uniform.

System Replacement & Upgrades

When your old system costs more to repair than replace, we offer smart, energy-efficient upgrades. We provide seamless transitions to new, reliable units with transparent pricing and expert installation across LA and Orange County. We also offer FREE estimates for replacements.


  • Aging System: Your current AC or furnace is over 10-15 years old and frequently breaks down.
  • Frequent Repairs: Constant service calls and costly part replacements are draining your budget.
  • High Energy Bills: Noticeable spikes in utility costs without changes in usage, indicating poor efficiency.
  • Uneven Heating/Cooling: Hot and cold spots throughout your property, even with the system running constantly.


Is It Time for HVAC System Replacement?

Air conditioner unit on a concrete pad in a grassy backyard. Beige house in background.

New AC System Installation

Whether for new construction or upgrading an existing property, we ensure your new AC system is perfectly sized and professionally installed for optimal performance and efficiency. We are proud to offer FREE installation estimates.


  • Proper Sizing: Ensuring the AC unit perfectly matches your space for maximum cooling efficiency.
  • Ductwork Integration: Seamless connection and sealing of new AC to existing or new duct systems.
  • Thermostat Setup: Installation and programming of smart or traditional thermostats for optimal control.
  • Post-Installation Testing: Rigorous testing to confirm flawless operation and peak energy performance.


Expert AC Installation with Free Estimates for Peak Performance.

Hand pressing a button on a white thermostat; displays temperature and time.

Furnace & Heating Solutions

From meticulous furnace repair to the installation of new, high-efficiency heating systems, we cover all your needs. Ensure your property is warm when needed with our licensed expertise, and get a FREE estimate on new furnace installations.


  • Furnace Malfunctions: Pilot light issues, faulty igniters, or blower motor failures leaving your home cold.
  • Heat Pump Service: Repair, maintenance, and installation of efficient heat pump systems for year-round comfort.
  • Thermostat Control: Installation and calibration of heating thermostats for precise temperature management.
  • Safety Inspections: Thorough checks of gas lines, carbon monoxide detectors, and system components.


Safe, Dependable Warmth with Free Installation Estimates.