5. The term of unit
1) Kcal : Adding or releasing heat to or from a substance changes its temperature. This change of temperature is
in proportion the heat added or released. This heat is called calorie which is expressed in Kcal or cal.
1 Kcal is equal to the amount of heat required to raise the 1°C temperature of 1kg water 4°C.
2) BTU : 1 BTU is equal to the amount of heat required to raise the 1°F temperature of 1 lb water.
• 1 Kcal = 3.968 BTU, 1 BTU = 0.252 Kcal
3) RT : 1 RT (Refrigerating Ton) is equal to the capacity which makes 1 Ton water 0°C into ice 0°C in 24 hours. It
is expressed in calorie required to freeze water 1 Ton water 32°F(2000 lb) into ice 32°F, and when using
the solidification latent heat of water, 1RT is as follows
• 1 RT = 144BTU/lb x 2000 lb/24hr = 12,000 BTU/hr = 3,024 Kcal/hr = 3.517 KW
4) Hp : Horse Power
• 1 Hp = 0.75 KW = 645 Kcal/h, 1W = 0.86 Kcal/h
5) Temperature conversion (°C
↔
°F)
• °F = 9/5°C + 32, °C = 5/9 (°F-32)
6) Area or volume conversion
• 1m
2
= 10.764 ft
2
, 1m
3
= 35.3165 ft
3
7) Weight conversion
• 1Kg = 2.2 lb, 1 lb = 0.45 Kg
8) Unit conversion table
Classification
BTU/h
Kcal/h
W
KJ
Hp
RT
1BTU/h
1
0.252
0.293
1.055
0.00039
0.000083
1Kcal/h
3.968
1
1.163
4.186
0.00155
0.000329
1W
3.413
0.86
1
3.601
0.00133
0.000283
1KJ
0.948
0.239
0.278
1
0.00037
0.000079
1Hp
2559
645
750
2700
1
0.212
1RT
12000
3024
3516
12660
4.68
1
TCL Air Conditioner Service Manual
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