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the full forms of some common terms used in HVAC systems

 Here are the full forms of some common terms used in HVAC systems:


1. HVAC - Heating, Ventilation, and Air Conditioning

2. AC - Air Conditioning

3. AHU - Air Handling Unit

4. CFM - Cubic Feet per Minute (air flow rate)

5. DX - Direct Expansion (type of cooling coil)

6. ERV - Energy Recovery Ventilator

7. FCU - Fan Coil Unit

8. GPM - Gallons per Minute (water flow rate)

9. HSPF - Heating Seasonal Performance Factor (heat pump efficiency)

10. SEER - Seasonal Energy Efficiency Ratio (AC efficiency)

11. SCFM - Standard Cubic Feet per Minute (air flow rate at standard conditions)

12. TR - Tonnage (cooling capacity, 1 TR = 12,000 BTU/h)

13. VAV - Variable Air Volume (type of air distribution system)

14. VRV - Variable Refrigerant Volume (type of air conditioning system)

15. VFD - Variable Frequency Drive (type of motor control)


These terms are commonly used in the design, installation, and operation of HVAC systems.

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