Trench Heating

Discrete under floor system for combating heat losses at glazed elevations

Performance

Trench heating output will depend on tube diameter, number of elements etc. Output for the standard range of nine models is summarised below.

Outputs are based on a LPHW mean water temperature of 80°C, an entering air temperature of 20°C and a water velocity of 1 m/s.

Model

*Output
watts/metre

Tube Diametre
mm

LTU/J 250 15 or 22
 
LTU/JJ/S 380 15 or 22
 
LTU/N 485 15, 22 or 28
 
LTU/W 645 22 or 28
 
LTU/JJ 645 15 or 22
 
LTU/FF 645 15 or 22
 
LTU/FN 805 15 or 22
 
LTU/NN 970 15, 22 or 28
 
LTU/WW 1290 22 or 28
 

* All outputs in watts/metre are for finned length of element and based on
LPHW 80° m.w.t., 20°C e.a.t. and 1.0m/s water velocity.

Outputs for variations in water velocities and temperature variations can be used using the correction factors listed below.

Correction Factors   
Variations in water velocity  Variations in  ΔT 

Water
 Velocity in metres/sec

 Correction Factor

  ΔTm.w.t. - e.a.t.
K

 Correction Factor

 0.08  0.90  30  0.38
 0.10  0.91  35  0.47
 0.15  0.92  40  0.57
 0.25  0.93  45  0.67
 0.28  0.94  50  0.77
 0.30  0.95  55  0.88
 0.35  0.96  56  0.90
 0.50  0.97  57  0.93
 0.75  0.98  58  0.95
 1.00  0.99  59  0.98
 1.35  1.00  60  1.00
 2.00  1.02  65  1.12
   1.03  70  1.24
     75  1.34
     80  1.47

 


Newsletter sign up

Receive our quarterly newsletter