Onix Tubing Installation Manual

PRESSURE DROP (Feet of Head Pressure Drop per Lineal Foot of Hose)
Watts Radiant PRESSURE DROP CHART FOR Onix
50% Propylene Glycol/50% Water
TM
TM
FLOW RATE (GPM) AT 20 F T
Q
s
HEAT REQUIRED (BTU/h) FOR AREA SERVED BY ONE CIRCUIT
0.0001
0.001 0.01 0.10.03 1.0
3/8" Tubing
1/2" Tubing
5/8" Tubing
3/4" Tubing
40,000
30,000
20,000
10,000
9,000
8,000
7,000
6,000
5,000
4,000
3,000
2,000
1,000
900
800
700
600
500
1 ft/sec
2 ft/sec
3 ft/sec
7 ft/sec
1.5 ft/sec
5 ft/sec
4 ft/sec
6 ft/sec
5
4
3
2
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.09
0.08
0.07
0.06
1" Tubing
0.05
50,000
Notes: 1. The heat required is the energy the boiler must deliver for the calculated heat output of a circuit. If only the net heat output of
the circuit is known, multiply by 1.1 to get Q
s
, assuming the back and edges are insulated or space below is heated.
2. If the ∆T is different from 20°F, the value of Q
s
must be multiplied by 20/∆T.
3. Numbers from 1-7 in graph show the average water velocity in the hose (ft./sec).
4. This chart is for 50% propylene glycol/50% water mixture only.
5. Remember to correct the flow rate for the different heat carrying capacity of propylene glycol, as opposed to plain water.
page 66 Watts Radiant: Onix Installation Manual
Typical pressure drop chart for propylene glycol systems.
Appendix