Mini Splits for Garages: Your Ultimate Guide to Keeping Your Workspace Cool and Comfortable

Maintaining a comfortable temperature in your garage workspace can be a challenge. Garages are often detached from the main house and lack good insulation, allowing heat and cold to easily permeate the space. Installing a mini split air conditioner designed specifically for garages is an efficient and affordable way to take control over your environment so you can work or pursue hobbies in comfort no matter the weather outside. This comprehensive guide covers everything you need to know when considering a mini split system for your garage, from choosing the right size unit to proper installation and maintenance. Read on to make an informed decision about cooling and heating your invaluable workshop area.

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mini split for garage

mini split for garage

Selecting an appropriately sized mini split system for your garage’s dimensions, climate, and budget is crucial to receive optimal performance.

Benefits of Using a Mini Split in Your Garage


Mini split air conditioning and heating systems offer numerous advantages over traditional HVAC units when it comes to workshops, garages, and other detached structures:


  • Energy Efficient Cooling and Heating: Mini splits only condition the specific room where the indoor unit is located rather than the whole building. This allows them to save up to 30% on electricity costs versus central air conditioning.
  • Precise Temperature Control: The inverter-driven technology within mini splits reacts quickly to subtle temperature changes, avoiding drastic hot and cold fluctuations. This keeps conditions stable so you can work comfortably.
  • Quiet Operation: Designed for residential use, mini splits operate very quietly – most produce less than 45 decibels of sound. This allows you to take phone calls or enjoy music without cranking up the volume.
  • Compact Size: The components are small and mount discretely on walls and ceilings, saving valuable floor and wall space within your garage.


Clearly, mini split air conditioners allow garages and workshops to be cooled in an affordable, efficient, and non-disruptive manner. But choosing the right system and having it properly installed are key to garnering all the benefits.

Choosing the Right Mini Split Air Conditioner for Your Garage


Selecting an appropriately sized mini split system for your garage’s dimensions, climate, and budget is crucial to receive optimal performance. Consider the following factors:


Garage Size

  • Measure the length, width, and height of your garage interior in feet to determine its total volume in cubic feet
  • Consult sizing charts to choose a BTU rating that matches the size of your space
  • Too small = won’t cool effectively
  • Too large = less efficiency and humidity control


Garage Size (sq. ft.)

Minimum BTU Rating

Up to 150















Climate Conditions

  • Hot and humid climates require 20-30% more cooling capacity
  • Heat load calculations factor sun exposure and insulation levels
  • Choose higher SEER ratings to save on summer cooling bills



  • Single vs. multi-zone systems
  • Inverter vs. fixed speed compressor
  • WiFi connectivity, timers, thermostat integration, etc.
  • Warranties on parts and labor (5 years minimum)



  • Installation costs vary based on system complexity, ductwork needed, electrical upgrades required, etc.
  • Estimate $5,000 - $8,000 for a professionally installed single-zone system


While it may be tempting to simply purchase the least expensive garage air conditioner available, choosing one that’s properly matched to your space will save you money and hassle in the long run. Consulting with an HVAC professional is wise to ensure you get the right system before purchasing and installing a mini split unit.

How to Install a Mini Split Air Conditioner in Your Garage

How to Install a Mini Split Air Conditioner in Your Garage

Once you’ve selected the ideal mini split system, it’s time for installation. While a skilled HVAC technician is best suited for this process, you can take a DIY approach if you are comfortable working with refrigerant lines, condensate drains, electrical connections, and the structural considerations the units require.


Here is an overview of mini split installation tasks:


1. Choose Installation Locations

  • Mount the compact indoor unit on an interior wall with ample clearance
  • Install the outdoor condenser unit on an exterior wall with exposure to fresh air
  • Avoid locations that are difficult to access when maintenance is needed


2. Mount the Indoor Evaporator Unit

  • Install a mounting bracket positioned properly on the wall
  • Ensure the bracket can support the unit weight (usually 25-35 lbs)
  • Leave room for service access and airflow clearance


3. Mount the Outdoor Condenser

  • Select a site with proper sun/shade exposure
  • Install a mounting base that raises the unit off the ground
  • Maintain clearance from fences, vegetation, other structures
  • Allow proper airflow and drainage underneath


4. Add Support Structures

  • Build structural overhangs above the units if lacking roof eave protection
  • Install wind guards in very windy locations if unit lacks built-in protection


5. Connect Refrigerant Piping

  • Run A/C refrigerant piping between the indoor and outdoor units
  • Add refrigerant oil and vacuum pump the lines to remove moisture
  • Insulate lines to prevent condensation and efficiency losses


6. Install Condensate Drain Line

  • Run PVC pipe from indoor unit to exterior to remove moisture
  • Maintain downward slope for proper drainage
  • Condensate pump may be needed if drainage is uphill


7. Make Electrical Connections

  • Supply power wiring to both units per manufacturer specifications
  • Use proper conduit, disconnect boxes, overcurrent protection
  • Connect control wiring between the units
  • Ground all components appropriately


8. Evacuate Air & Charge Refrigerant

  • Pull vacuum on line set and indoor coil to remove moisture
  • Charge system with precise amount of R410a refrigerant
  • Avoid over/under charging to prevent damage


9. Test Operation

  • Power up the mini split system
  • Configure thermostat settings appropriately
  • Verify cooling function and proper drainage
  • Scan for refrigerant leaks during initial run time


While condensing the full installation process into a few paragraphs glosses over critical details, it provides a general overview of the end-to-end procedure. Employing a qualified technician ensures proper execution.

Maintaining Your Garage Mini Split for Peak Performance


While mini split systems require very little maintenance compared to full-sized HVAC systems, following some basic preventative measures will keep your garage air conditioner running efficiently for years.


Air Filter Changes

  • Check filters monthly and replace as needed, typically every 3-6 months
  • Clogged filters reduce airflow and efficiency


Clear Debris and Vegetation

  • Remove fallen leaves, grass clippings from the outdoor unit area
  • Trim back encroaching tree branches and plant growth


Annual Professional Check-Ups

  • HVAC technicians check refrigerant charge, electrical connections, all components for wear/corrosion, etc.
  • Tuning ups catch minor issues before they become major repairs


Clean Indoor and Outdoor Coils

  • Use approved evaporator and condenser coil cleaner for best results
  • Avoid water pressure above 30 PSI to prevent fin damage


By properly maintaining your garage mini split system, you can minimize repair bills and extend its operating life by years.

Concluding Thoughts – Beat the Garage Heat with a Mini Split


Adding air conditioning to your garage or workshop with a compact, energy efficient ductless mini split system allows you take full advantage of the space regardless of outdoor weather conditions. Investing in the right sized unit professionally installed delivers comfort, lower energy consumption, and convenience. Hopefully this guide provided you with detailed advice on selecting cooling and heating solutions tailored specifically for detached garage and workshop environments. The next step is to request quotes from qualified HVAC installation contractors in your local area.


For mini split installations in your garage, contact us at or call to speak with an expert and receive a free quote. We specialize in ductless heating and cooling systems for workshops, garages, and detached spaces. Beat the heat and cold this year so your workspace is always the perfect place to create!

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