The answer to 'ductless system not heating' is that there are several common causes, including a refrigerant leak, a malfunctioning compressor, or an issue with the indoor or outdoor unit. Symptoms may include the system not producing any warm air, the compressor not running, or the unit cycling on and off frequently.
Some potential solutions include checking the refrigerant levels, cleaning or replacing the air filters, and ensuring the outdoor unit is free of debris. However, many ductless system repairs should be handled by a professional HVAC technician, as they require specialized knowledge and tools to diagnose and fix properly.