5 / 12
THERMAL MANAGEMENT SOLUTIONS
EN-RaychemWinterGardH900-IM-H53665 01/13
HEATING cAbLE DESIGN
Only WinterGard Wet H612 120-V and H622 240-V heating cables
are suitable for use with the H900 power connection kit for roof
and gutter de-icing applications.
1. calculate the heating cable length required.
Length = A + b + c + D + E + F + G
A Roof edge length (ft) x feet of heating cable per foot of roof edge
(From Table 5)
b Roof edge length (ft) x 0.5*
c Total gutter length (ft)
D Total downspout length (ft) + 1 (ft)
E 1 ft for each power connection
F 2 ft for each splice connection
G 3 ft for each tee connection
= Total heating cable length (ft)
* Roof extension: This length allows the heating cable to extend into the gutter
to provide a continuous drain path, or where no gutters are present, extends
beyond the roof edge to form a drip loop.
Note: Pentair Thermal Management recommends a gutter and downspouts to
provide a continuous path for melted water.
Table 5. WinterGard Wet cable length for roof de-icing
Standing seam metal roof:
Eave overhang
Shingle roof
18 inch seam 24 inch seam
0
2.0 ft
2.5 ft
2.0 ft
12"
2.8 ft
2.8 ft
2.4 ft
24"
3.8 ft
3.6 ft
2.9 ft
36"
4.8 ft
4.3 ft
3.6 ft
Note: Pentair Thermal Management recommends a gutter and downspouts to
provide a continuous path for melted water.
Important: For the Pentair Thermal Management warranty to be
valid, you must comply with all the requirements outlined in these
guidelines.
All design information provided here is based on a “standard” shake
or shingle roof application. For any other application or method of
installation, consult Pentair Thermal Management at (800) 545-6258.
HEATING cAbLE INSTALLATION
1. prepare for installation.
• Store the heating cable in a clean, dry place.
• Use only the following Pentair Thermal Management accessories to
satisfy code and agency requirements:
- H900 WinterGard Plug-in Power Connection Kit (with end seal)
- H910 WinterGard Splice and Tee Kit (if splicing or teeing)
- H915 Downspout Hangers
- H913/H914 Roof Clips
• Carefully plan the routing of the heating cable for roof and gutter
de-icing.
• Make certain gutters and downspouts are free of leaves and other
debris.
2. cut the heating cable to length.
• Cut the heating cable to the length required. This can be done before or
after it is installed. Leave a minimum of 1 foot extra heating cable for
connection to power. For splice and tee connections leave a minimum
of 1 foot for each section of heating cable. WinterGard heating cable
can be cut to length without affecting its heat output per foot.
• Protect the heating cable ends from moisture and mechanical damage
if they will be left exposed before connection.
3. position and attach the heating cable.
On roofs
• Loop the heating cable on the overhang area of the roof. This is the
part that extends past the building wall. Extend the bottom of each
heating cable loop over the roof edge and, using a UV-resistant cable
tie, connect the bottom of each loop to the cable running in the gutter
to ensure a drainage channel off the roof and into the gutter and
downspout. The cable running in the gutter should remain against
the bottom of the gutter. Extend the top of each heating cable loop
beyond where the wall joins the roof. Pentair Thermal Management
recommends 2-foot clip-spacing along the roof edge. See the “Heating
cable design” section (Table 5) for spacing and layout information.
• Use WinterGard H913/H914 roof clips to attach heating cable to the
roof surface. One kit contains ten double roof clips for approximately
7 linear feet of roof edge. One H914 kit contains 50 roof clips for
approximately 35 linear feet of roof edge.
For flat roofs, the heating cable can be spaced as needed to create
runoff paths for melting ice and snow. Use single-ended clips located
at 3-foot intervals to secure the cable to the roof.
Roof clips may be attached to a shake or shingle roof with nails or
screws. Reseal the nail or screw holes if necessary before installing
heating cable in the clips. Roof clips may be attached to a metal roof
using screw, nail or adhesive. (See H56723 installation instruction for
more details.)
• A barrier (snow fence) can be placed on the roof above the heating
cable. This prevents damage to the cable and keeps the installation
from coming loose due to ice slides. If desired, the heating cable can
be attached to the barrier with UV-resistant cable ties, instead of
using roof clips. Do not use wire or other materials because they may
damage the heating cable.
In gutters and downspouts
• Run heating cable along gutters and into downspouts, ending below
the freezing level. Permanent attachment of the cable to the gutter
bottom is not necessary. Loop the heating cable in downspouts if
convenient, such as when the downspout is not at the end of the run,
or use the H910 splice and tee kit to tee down the downspout.
• Use WinterGard H915 downspout hangers to protect the heating cable
from fraying and from damage from sharp edges and to provide strain
relief. Refer to the H915 kit instructions for installation details.
• Use WinterGard H913/H914 roof clips to route heating cable into
and out of the gutter in such a way as to prevent abrasion to the
cable. Protect all cable that protrudes past the lower opening of the
downspout.
H900 DESIGN AND INSTALLATION INFORMATION FOR ROOF AND GUTTER DE-IcING ONLy
(WinterGard Wet H612, and H622 Heating cables)
Example:
Roof edge:
40 ft
Roof overhang:
1 ft
Roof gutter:
40 ft
Downspout:
15 ft
Power connection:
2 ea
Tee connection:
1 ea
Voltage available:
120 V
CB Size Available:
15 A
Start-up temperature: 0 °F
WinterGard Wet heating cable required:
A Roof edge:
40 ft x 2.0
(from Table 5) = 80 ft
b Roof extension:
= 40 ft x 0.5
= 20 ft
c Roof gutter:
= 40 ft
D Downspout:
= 15 ft + 1 ft
= 16 ft
E Power connection:
1 ft x 2 ea
= 2 ft
F Splice Connections: = 0
G Tee connection:
3 ft x 1 ea
= 3 ft
Total WinterGard Wet heating cable
required:
= 161 ft**
** This total exceeds 100-ft maximum circuit length (see
Table 6), therefore two separate circuits are required.