Can MRCOOL AC Be Used as Heater: A Comprehensive Guide

MRCOOL air conditioners can indeed be used as heaters, as they are heat pumps that can both heat and cool. MRCOOL mini split heat pumps are known for their efficiency, ability to provide both heating and cooling, and custom zone comfort. They can effectively heat homes at temperatures as low as -15 degrees Fahrenheit, making them suitable for most climates and conditions throughout the United States.

Understanding MRCOOL Mini Split Heat Pumps

MRCOOL mini split heat pumps are a type of ductless HVAC system that can both heat and cool a space. These systems consist of an outdoor compressor/condenser unit and one or more indoor air handling units, connected by refrigerant lines. The key advantage of a mini split system is its ability to provide targeted, zone-based heating and cooling, allowing homeowners to control the temperature in specific areas of their home.

How MRCOOL Mini Split Heat Pumps Work

MRCOOL mini split heat pumps use a refrigeration cycle to transfer heat between the indoor and outdoor units. During the heating mode, the outdoor unit absorbs heat from the outside air and transfers it to the indoor unit, which then distributes the warm air into the living space. This process is reversed during the cooling mode, with the outdoor unit dissipating the heat from the indoor air.

Heating Capacity and Efficiency

The heating capacity of a MRCOOL mini split system depends on the model selected, with more zones and higher BTU ratings providing greater heating potential. For example, a 10,000 BTU system can comfortably heat an area of around 450 square feet, while a 24,000 BTU system can effectively heat up to 1,500 square feet.

MRCOOL mini split heat pumps are known for their high energy efficiency, with many models achieving SEER (Seasonal Energy Efficiency Ratio) and HSPF (Heating Seasonal Performance Factor) ratings that exceed the minimum requirements set by the U.S. Department of Energy. This translates to lower energy bills and a more sustainable heating solution for homeowners.

Preparing for MRCOOL Mini Split Heat Pump Installation

can MRCOOL ac be used as heater

Before installing a MRCOOL mini split heat pump, it’s essential to properly size the system for the space being heated. This involves calculating the heating load, which takes into account factors such as the square footage, insulation, and climate conditions of the home.

Selecting the Right MRCOOL Mini Split System

When choosing a MRCOOL mini split system, consider the following factors:

  1. Heating and Cooling Capacity: Ensure the system is properly sized for the space, with enough BTUs to effectively heat and cool the area.
  2. Number of Zones: Determine the number of indoor units needed to provide targeted comfort in the desired areas.
  3. Energy Efficiency: Look for models with high SEER and HSPF ratings to maximize energy savings.
  4. Noise Level: Consider the sound output of the indoor and outdoor units, especially if they will be installed in close proximity to living spaces.
  5. Warranty: Review the manufacturer’s warranty coverage, including any limitations or exclusions.

Preparing the Installation Site

Before the MRCOOL mini split heat pump installation, ensure the following:

  1. Outdoor Unit Placement: Choose a location for the outdoor unit that is level, well-ventilated, and protected from direct sunlight and heavy snowfall.
  2. Indoor Unit Placement: Identify suitable locations for the indoor units, considering factors such as airflow, accessibility, and aesthetics.
  3. Electrical and Plumbing Preparations: Ensure the necessary electrical and plumbing infrastructure is in place to support the mini split system.
  4. Permits and Inspections: Verify any local building codes or regulations that may require permits or inspections for the installation.

Installing and Maintaining MRCOOL Mini Split Heat Pumps

The installation of a MRCOOL mini split heat pump system should be performed by a licensed and experienced HVAC technician to ensure proper setup and optimal performance.

Step-by-Step Installation Process

  1. Outdoor Unit Placement: The outdoor unit should be placed on a level, stable surface, with adequate clearance around it for airflow and maintenance.
  2. Indoor Unit Mounting: The indoor units should be securely mounted on the wall or ceiling, with consideration for airflow and accessibility.
  3. Refrigerant Line Installation: The refrigerant lines connecting the indoor and outdoor units must be properly sized, insulated, and routed to minimize heat loss or gain.
  4. Electrical Connections: The system’s electrical connections, including the power supply and control wiring, must be made in accordance with local codes and the manufacturer’s instructions.
  5. Commissioning and Testing: The HVAC technician will perform a series of tests to ensure the system is functioning correctly and to make any necessary adjustments.

Maintaining MRCOOL Mini Split Heat Pumps

To ensure the long-term performance and efficiency of your MRCOOL mini split heat pump, regular maintenance is essential. This includes:

  1. Cleaning the Filters: The indoor unit’s air filters should be cleaned or replaced periodically to maintain optimal airflow and system performance.
  2. Outdoor Unit Maintenance: Keep the outdoor unit free of debris, snow, and ice to prevent any obstructions to airflow and heat transfer.
  3. Refrigerant Checks: Periodically check the refrigerant levels and have the system serviced by a qualified technician if any leaks are detected.
  4. System Inspections: Schedule annual inspections by a licensed HVAC technician to identify and address any potential issues before they become more serious.

Troubleshooting MRCOOL Mini Split Heat Pumps

In the event of any issues with your MRCOOL mini split heat pump, it’s important to address them promptly to maintain optimal performance and prevent further damage.

Common Issues and Solutions

  1. Insufficient Heating: If the system is not providing enough heat, check the outdoor unit for any obstructions, ensure the filters are clean, and verify that the system is properly sized for the space.
  2. Icing on the Outdoor Unit: If the outdoor unit is accumulating ice, ensure the defrost cycle is functioning correctly and that the unit is not obstructed by snow or debris.
  3. Compressor Failure: If the compressor fails, it may be covered under the manufacturer’s warranty, but the user may be responsible for shipping costs.
  4. Refrigerant Leaks: Any refrigerant leaks should be addressed by a licensed HVAC technician to prevent further damage and ensure the system is operating safely.

Contacting MRCOOL for Support

If you encounter any issues with your MRCOOL mini split heat pump that you are unable to resolve, it’s recommended to contact the manufacturer’s customer support team for assistance. They can provide guidance on troubleshooting, warranty claims, and any other questions or concerns you may have.


MRCOOL mini split heat pumps can be an effective and efficient heating solution for residential homes, providing targeted comfort and energy savings. By understanding the system’s capabilities, properly sizing and installing the equipment, and maintaining it regularly, homeowners can enjoy the benefits of MRCOOL’s heating and cooling technology. However, it’s important to be aware of the system’s limitations, such as warranty coverage and potential longevity issues, to make an informed decision when choosing a MRCOOL mini split heat pump.

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