4
Design & Selection
3 Selection of the Underfloor Coils
3.1 Calculation of Unit Load for Floor Heating
Empirical Values of Floor Heating Load Per Square Meter
House W/m
2
Dining Room
100~120
Mater Room
100~110
Guest Room
110~130
Study Room
90~110
Villa W/m
2
Dining Room
110~140
Mater Room
100~120
Guest Room
100~130
Study Room
100~120
Notes
①
Villas whose load is generally larger than the houses should take the value between the middle and the
maximum empirical values listed above.
②
The top lever whose load is generally larger than the middle or bottom layer should take the maximum
empirical value.
③
The guest room whose load is generally much large should take the value between the intermediate and
the maximum empirical values listed above.
④
For those whose external walls or glass areas are large, it is recommended to take the load calculation.
⑤
The heating load for the bathroom is generally 500W/room.
3.2 Selection of Tube Spacing of the Underfloor Coils
Tube spacing of the underfloor coils which will directly affect heat dissipation of the floor depends on the
tube material, indoor design temperature, supply water temperature and floor material.
Heat Dissipation of Commonly Used Coils
(Tube material: PE-X, Indoor temperature:18°C, Average water temperature:45°C)
Floor Material
Thermal Resistance
m
2
·K/W
Tube Spacing
mm
Heat Dissipation
W/m
2
Tube Spacing
mm
Heat Dissipation
W/m
2
Stone
0.02
200
147.0
150
159.8
Wood
0.075
200
111.2
150
117.8
The dissipated heat of the floor coil is larger than the load for the floor heating system; however the
deviation cannot be larger than 10%.
3.3 Selection of Loop Quantity of Coils for Each Room
3.3.1Type of Underfloor Coils
When selecting underfloor coils, we should consider both their comfortability and heating capacity. The most
commonly used coils are as shown below.
Square-shaped Coil (Recommended)
U-shaped Coil
Length of coils are calculated as below:
Square-shaped coil: =L*W/tube spacing=area/tube spacing
U-shaped coil: =L-1+L*W/tube spacing=L-1+area/tube spacing
The reason why the square-shaped coils are recommended is because they can keep even temperature
Summary of Contents for Versati II Series
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