Insulated Copper Tubes - Heat Loss

Heat loss to surrounding air from insulated copper tubes. The heat loss is based on temperature difference 55°C (99°F) with insulation thickness 25 mm (1 inch) and conductivity coefficient k = 0.043 W/m°C (0.3 Btu in/ft²hr°F).

Nominal Bore (mm)	Nominal Bore (inches)	Heat Loss (W/m)	Heat Loss (Btu/hr ft)
22	3/4	8	8
28	1	10	10
42	1 1/2	11.5	12
54	2	14.5	15
67	2 1/2	16	17
76	3	19	20

Conversion Factors

1 W = 3.4 Btu/hr
1 ft (foot) = 0.3048 m

Parameters

Temperature Difference: 55°C (99°F)
Insulation Thickness: 25 mm (1 inch)
Conductivity Coefficient (k): 0.043 W/m°C (0.3 Btu in/ft²hr°F)