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2.
Fire Sprinkler
System Freeze
Protection
1.
Pipe Freeze
Protection and
Flow Maintenance
3.
Roof and Gutter
De-Icing
4.
Surface Snow
Melting – MI
5.
Surface Snow
Melting and Anti-
Icing – ElectroMelt
6.
Freezer Frost
Heave Prevention
7.
Floor Heating
8.
T
echnical Data
Sheets
Pipe Freeze Protection and Flow Maintenance Design
Table 5 Power Output Correction Factors
voltage correction factors
5XL1
8XL1
5XL2
8XL2
12XL2
120 V
1 .00
1 .00
–
–
–
208 V
–
–
1 .00
1 .00
1 .00
240 V
–
–
1 .12
1 .12
1 .14
277 V
–
–
1 .29
1 .27
1 .30
Plastic pipe correction factor
(With AT-180 Aluminum tape)
0 .75
0 .75
0 .75
0 .75
0 .75
Confirm that the corrected power output of the heating cable selected is greater than the
corrected pipe heat loss (Q
corrected
) . If Q
corrected
is greater than the power output of the
highest-rated heating cable, you can:
• Use two or more heating cables run in parallel
• Use thicker insulation to reduce heat loss
• Use insulation material with a lower k factor to reduce heat loss
Example: Pipe Freeze Protection – Water Piping
Pipe maintain temperature (T
m
) 40°F (4°C)
(from Step 1)
Q
corrected
Q
corrected
= 3 .9 W/ft @ T
m
40°F (13 .1 W/m @ T
m
4°C)
Supply voltage
120 V
(from Step 1)
Pipe material
Plastic
(from Step 1)
Select heating cable:
Q
b
= 3 .9 W/ft @ T
m
40°F
(from Step 1)
5XL1= 5 .6 W/ft @ 40°F
(from Fig. 13)
Supply voltage correction factor
1 .00
(from Table 5)
Pipe material correction factor
Plastic = 0 .75
(from Table 5)
Corrected heating cable power
5 .6 W/ft x 1 .00 x 0 .75 = 4 .2 W/ft
Selected heating cable
5XL1
Example: Flow Maintenance – Greasy Waste Line
Pipe maintain temperature (T
m
) 110°F (43°C)
(from Step 1)
Q
corrected
3 .9 W/ft @ T
m
110°F (13 .1W/m @ T
m
43°C)
Supply voltage
208 V
(from Step 1)
Pipe material
Metal
(from Step 1)
Select heating cable:
Q
b
= 3 .9 W/ft @ T
m
110°F
(from Step 1)
12XL2= 7 .0 W/ft @110°F
(from Fig. 13)
Supply voltage correction factor
1 .00
(from Table 5)
Pipe material correction factor
Metal = 1 .00
Corrected heating cable power
7 .0 x 1 .00 x 1 .00 = 7 .0 W/ft
Selected heating cable
12XL2
