Definition:
Ductless HVAC systems are heating and cooling solutions that don’t require traditional ductwork, making them ideal for retrofitting older buildings or adding climate control to specific areas. These systems typically consist of an outdoor unit connected to one or more indoor air handlers, allowing for flexible installation and individualized temperature control in different zones.
Additional Facts
- Ductless mini-splits: These systems consist of an outdoor unit and one or more indoor air-handling units, connected by a small conduit.
- Radiant heating: This method uses electric cables or hot-water tubing installed beneath the floor or within walls to heat spaces without air ducts.
- Window AC units: These self-contained systems are designed to cool individual rooms and can be easily installed in existing windows without ductwork.
- Portable air conditioners: These freestanding units can be moved from room to room and only require a small exhaust hose to vent hot air outside.
- High-velocity systems: These use small, flexible tubing instead of traditional large ducts to deliver conditioned air, making them ideal for older buildings with limited space.
Fundamental Mechanisms
| Mechanism | Purpose | Key Components | Critical Issue | Impact of Failure |
|---|---|---|---|---|
| Mini-Split Systems | Provide heating and cooling to individual rooms or zones | Indoor air handling unit, outdoor condenser unit, refrigerant lines | Refrigerant leaks, compressor failure | Loss of heating/cooling in specific areas, increased energy costs |
| Radiant Heating | Warm spaces through radiation from floors, walls, or ceilings | Heating elements (electric or hydronic), thermostats, insulation | Leaks in hydronic systems, electrical failures | Uneven heating, water damage, increased energy consumption |
| Chilled Beams | Provide cooling (and sometimes heating) using convection | Chilled water pipes, heat exchanger fins, ventilation system | Condensation on beams, improper air circulation | Reduced cooling efficiency, potential water damage, poor air quality |
| Variable Refrigerant Flow (VRF) | Offer simultaneous heating and cooling to multiple zones | Outdoor condensing unit, multiple indoor units, refrigerant lines, central controller | Refrigerant leaks, compressor issues, control system failures | Zone-specific comfort issues, system-wide inefficiency, high repair costs |
| Packaged Terminal Air Conditioners (PTAC) | Provide heating and cooling for individual rooms, often in hotels | Compressor, condenser, evaporator, fan, heating element (optional) | Compressor failure, fan motor issues, clogged filters | Room-specific comfort problems, noise issues, increased energy use |