Common units and conversions:

1 MW=1000 KW

1 KW=1000 W

1 KW=861Kcal/h (kcal)=0.39 P (cooling capacity)

1 W=1 J/s (joules per second)

0.1MPa=1 kg/cm2=10 meters of water column=100KPa

1 USTR (US cold ton)=3024Kcal/h=3517W (cold capacity)

1 BTU (British thermal unit)=0.252kcal/h=1055J

1 BTU/H (British thermal units/hour)=0.252kcal/h

1 BTU/H (British thermal units/hour)=0.2931W (cooling capacity)

1 MTU/H (thousands of British thermal units/hour)=0.2931KW (cooling capacity)

1 HP (electricity)=0.75KW (electricity)

1 KW=1.34HP

1 RT (cooling capacity)=3.517KW (cooling capacity)

1 KW (cooling capacity)=0.284RT=860kcal/h=3.412MBH (103 British thermal units/hour)

1 P (cooling capacity)=2200kcal/h=2.56KW

1 kcal/h=1.163W

1 W=0.86kcal/h

F (Fahrenheit)=9/5 ℃+32

℃ (degrees Celsius)=(F-32) 5/9

1 CFM (cubic feet per minute)=1.699M ³/ H=0.4719 l/s

1 M ³/ H=0.5886 CFM (cubic feet per minute)

1 l/s=2.119 CFM (cubic feet per minute)

1 GPM (gallons per minute)=0.06308 l/s

1 l/s=15.85 GPM (gallons per minute)

1 kg/cm2=105=10mH2O=1bar=0.1MPa

1 Pa=0.1mmH2O=0.0001mH2O

1 mH2O=104Pa=10kPa

Standard coal calorific value Hc=8.14 * 103W. h/kg

1 MJ (heat)=0.034125kg standard coal

1 Nm3 (natural gas)=1.2143kg standard coal

Knowledge that HVAC engineers must know:

1 kcal: When the temperature of 1 kilogram of water rises or falls by 1 ℃ under standard atmospheric pressure, the amount of heat absorbed or released is 1 kcal.

The phase change heat of 1 kilogram of ice is 80 kcal

1 kilogram of vaporization heat is 539 kcal

Maximum water density at 4 ℃

EER/COP/IPLv, the ratio of refrigeration capacity/heating capacity to input power. EER refers to the compressor, COP refers to the weighted average energy efficiency of the system and IPLV under different loads.

IPLV=2.3% * A+41.5% * B+46.1% * C+10.1% * D (weighted average)

Conversion Table for Common Units of Refrigeration: