Danfoss Ground application. Ice & Snow Melting Application guide

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Application manual | Ground application. Ice & Snow Melting

Ground application.
Ice & Snow Melting

Application manual

Let Danfoss do the work

Index

Danfoss Group is Denmark's largest industrial group. It is one of the world's
leading companies within heating, cooling and air-conditioning. The Danfoss
Group has more than 23000 employees and serves customers in more than 100
countries.

Danfoss is Europe’s leading brand of electrical cable heating systems and electric
pipe heating systems with over 70 years of experience. The production of
heating cables takes place in France and Poland while the head office is situated
in Denmark.

The value of experience

We have installed literally thousands of systems across the globe, in every
conceivable setting. This experience means that we can offer you practical
advice about precisely which components you need to get the best results at
the lowest cost.

Ground application. Ice & Snow Melting

This design guide presents Danfoss’s recommendations for design and
installation of ice and snow melting systems for ground application.
It provides guidance for heating cable positioning, electrical data and system
configurations.

Following Danfoss’s recommendations will ensure energy efficient, reliable and
maintenance free solution for constant wattage heating cables with 20 year
warranty.

1. Application Briefing 4

2. System Description 5

3. Products 6

4. System Design 10

5. Installation 15

6. Appendixes 19

7. Cases 24

Our quality management
system
and compliances

ISO 9001 TS 16949

ISO 14001

Along with full compliance with EU
directives and product approvals

1. Application Briefing

Winter weather costs

In recent years there have been
plenty of new stories about human
and financial costs caused by harsh
winter weather. Property damage,
increased maintenance expenses,
lost productivity, rising insurance
premiums, personal injuries and even
worse. Installation of Danfoss Ice &
Snow Melting System ensures a steady
solution to address cold weather
related problems.

Danfoss’s ice and snow melting system
is designed to provide safety for
people, vehicles, and buildings safety
through safe walking and driving
during winter and safety in terms of
less damage to buildings.

Ground solutions –
with a first class product range

By using Danfoss heating cables
and mats controlled by electronic
thermostats with moisture sensors,
you can cost-effectively protect large
areas such as parking areas, ramps
or pedestrian accesses to buildings
giving you convenience and safety
while saving a lot of tiring and time­consuming manual work.

Benefits

• Efficient snow removal - area is kept free from ice

and snow at all times

• No manual snow removal and salting becomes
unnecessary.

• Safe traffic and working areas for people

• Flexible system for most common surface covering

materials

• Cost saving for outdoor surface repair after winter

• Environment is protected against salting and

antifreeze related damages.

• Automatic ”Around the Clock” snow clearing service.

• Smart 2-zone control with low energy consumption

• Prioritizing – limited power output solution

• A maintenance free system with 20 year full
warranty on cables

One of the greatest advantages of
these systems is the most energy
efficient solution for the ground ice
and snow melting applications.

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Application manual · Ground application. Ice & Snow Melting · VGHWD102 · ©Danfoss

2. System Description

Main purpose of the system is to melt
and remove snow and ice from ground
surfaces.

The most common Danfoss ice and
snow melting ground applications
are in residential car parking areas,
driveways, pavements, outdoor steps,
loading platforms, ramps, bridges and
drainage areas. It is even possible to
melt snow and ice on mastic asphalt
surfaces by using special heating
cables.

When heating cables are installed
to melt snow or slippery ice on the
ground, safety and cost saving go hand
in hand.

It can be done manually or in a smart
way – by means of electrical Ice &
Snow Melting system with thermostat
control and moisture and temperature
sensors that can control 2 zones
simultaneously. Inactive during cold
but dry weather 2 zone control saves
energy and reduces costs.

The automatic regulation of the snow
melting system keeps areas free from
snow and passable at all times – night
and day.

When installing ice and snow melting
systems on steep slopes it may be
necessary to provide some drainage for
melted water at the slope bottom. The
drain system should also be protected
against ice formations.

Application manual · Ground application. Ice & Snow Melting · VGHWD102 · ©Danfoss

5

3. Products

Electrical heating system consists of
two major components:

• Heating element – heating cable or
heating mat;

• Thermostat with a temperature
sensor or regulator/controller with
temperature and moisture sensor(s).

Heating cables and mats for Ground
applications are usually installed into
concrete construction or into special
glue under tiles.

Danfoss heating cables and mats for
Ground applications are designed for
installation in concrete constructions
or into special glue under tiles. Usual
thickness of top/finish concrete layer
for outdoor applications is at least 5
cm. But the thickness should comply
with a ground construction and local
norms and regulations.

Heating cables used in ground
constructions are serial resistive cables,
single or twin conductor. Most of
cables and mats are manufactured as
ready-to-install heating elements wth
a specific length (i.e. 7, 10, 15, up to
229 m), with connecting power supply
cable (cold lead or cold tail) and sealed
joints (muffs or end terminals).

Heating elements

For Ground Ice and Snow Melting
systems the following resistive
(constant wattage) heating elements
can be used.

Heating cables:

• Twin conductor ECflex 18T and
ECflex 20T (230 V);

• Single conductor ECbasic 20S
(230 V);

• Twin conductor ECsafe 20T (230 V);

• Twin conductor ECsnow 20T and
ECsnow 30T (230/400 V);

Note. The number at the end of the
cable’s and mat’s name refers to its
linear output – W/m or area output –
W/m², at 230 V or 400 V.
Letter “T” means twin conductor
cable/mat (Twin), letter ”S” – single­conductor cable/mat (Single).

Danfoss resistive heating cables ensure
safe, efficient and economical ground
application.

To ensure long life-time and quality
all cables are thoroughly inspected
including tests for ohmic resistance,
high voltage and material control.

ECflex. It is a twin conductor fully
screened heating cable for installation
in concrete, pipe heating etc. The cable
complies with IEC 60800:2009 class M2,
and is designed for applications with
the high risk of mechanical damage.
It is supplied in readymade sets with
2,3 m cold lead, sealed joints and end
muffs.

Cable diameter is Ø 6,9 mm.

The cable is available for 230 V power
supply.

Cables of 18 and 20 W/m (230 V) linear
output are available.

Cable length:
ECflex 18T: 7,3-150 m ;
ECflex 20T: 7,1-148 m.

ECflex

Range of heating cables linear output
for ground application is usually
15-30 W/m. Danfoss ready-made
cables are available with 18, 20,
30 W/m output (for 230 and 400 V).

Most Danfoss cables are manufactured
and approved in accordance with the
latest revision of IEC 60800:2009, with
M2 mechanical strength class (for
rough concrete constructions).

The main type of Danfoss heating
cables is twin conductor heating
cables. Internal design of a modern
twin conductor ECflex cable are shown
in the figure below.

The most used heating elements for
Ground Ice and Snow Melting systems
are ECbasic, ECflex and ECsafe heating
cables.

Internal insulation ( XLPE)

Heating element (resistance thread)

ECflex heating cable construction

ECbasic. It’s a single conductor
screened heating cable complied with
IEC 60800:1992 class C and intended
for installation in concrete, for pipe
heating etc. It’s supplied in readymade
sets with 2 x 3 m cold leads and
2 sealed connection muffs.

Outer coating made of PVC
Protective screen foil (Aluminum)
Protective conductor

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Application manual · Ground application. Ice & Snow Melting · VGHWD102 · ©Danfoss

Cable diameter is Ø 5,5 mm.

ECbasic 20S is available with
20 W/m output for 230 V power supply.

Cable length:
ECbasic 20S, 230 V: 9-228 m.

ECbasic 20S readymade

ECsafe. It is a twin conductor fully
screened heating cable for installation
on roofs, in gutters, down drain pipes
and on the ground.
The cable has UV stable tough outer
sheath which complies with IEC
60800:2009 class M2, and is designed
for applications with the high risk of
mechanical damage. It is supplied in
readymade sets with 2,5 m cold lead,
sealed joints and end muffs.

The cable is available with linear
output of 20 W/m and 30 W/m in two
options for 230 V and 400 V power
supply.

Cable length:
ECsnow 20T, 230 V: 12-205 m;
ECsnow 30T, 230 V: 8,5-215 m.

Fixing

In case of heating cables application,it
is recommended to use fittingbands
to fix the cable to the base, e.g. ECfast
metal galvanized fitting band (see
Appendix A.2 ). It should be attached
to the ground (e.g. nailed down) in
parallel lines usually at intervals of
50 cm or using 2 meters of fitting
band per each square meter of cable
installation. The same applies to plastic
bands.

ECfast

As an alternative to control small areas
near private houses etc. EFET 130 wall
mounted room thermostat can be used.

All thermostats above are supplied
with a wire temperature sensor –
NTC 15 kOhm @25 °C, 3 m.

To control ice and snow melting
systems especially with high output
the best solution is EFIT 850 regulator/
controller with integrated ground and
roof moisture and temperature sensors.

EFIT 850 is a two-zone controller with
possibility of connection up to 4
sensors to provide maximum control
of the outdoor heating system.
Comparing to installations with typical
ground temperature measuring this
regulator ensures reducing energy
consumption costs by up to 40%.

Cable diameter is Ø 7 mm.

The cable is available with linear
output of 20 W/m for 230 V power
supply.

Cable length:
ECsafe 20T, 230 V: 6-194 m.

ECsnow. It is a twin conductor fully
screened heating cable for installation
mainly on roofs, in gutters, down drain
pipes. It can be an option for installation
on the ground too. The cable has UV
stable tough outer sheath, FEP con­ductor insulation, it complies with IEC
60800:2009 class M2 and is designed
for applications with the high risk of
mechanical damage. It is supplied in
readymade sets with 2,5 m cold lead,
sealed joints and end muffs.

Cable diameter is Ø 7 mm.

Control

Ice and snow melting systems
are different and require different
thermostats/regulators.

EFET/EFIT thermostats and regulators
are fitted with a complete set of
control functions for heating systems
for ice and snow melting of any type
and allow attaching external sensors
for measuring ground temperature as
well as control of moisture conditions.

The product range of controls is
designed for ground outdoor systems
including the following:

• thermostats with a temperature
sensor – EFET 330 (5…45 °C),
EFET 610;

• regulator with an integrated
temperature and moisture sensor(s)
– EFIT 850.

EFET 330 (5…45 °C)

with wire sensor in set

EFIT 850

with ground sensor

EFET 610

ECsnow

To control simple or low output
systems a thermostat with a ground
temperature sensor is recommended.
EFET 330 (5…45 °C) thermostat
with the DIN rail attachment is
recommended as a standard solution.
Also can be used EFET 610, IP44 with
on wall/pipe mounting.

Application manual · Ground application. Ice & Snow Melting · VGHWD102 · ©Danfoss

EFET 130

7

Zone support saves energy

The EFIT 850 lets you divide your area
in to 2 zones, e.g. a North and South
side. In this way it is possible to save
energy, when the South side is free
of ice and snow faster because of the
heat from
the sun.

Prioritizing – for limited power
output

You can prioritize between the zones,
e.g. if you have limited power output.
This way one zone is made ice and
snow free before focus is put on the
other zone.

Products – general overview for Ground ice and snow melting systems

Product Options Description

Resistive heating cable
ECflex

Resistive heating cable
ECbasic 20S

ECflex 18T, 230 V;
ECflex 20T, 230 V

ECbasic20S,
230 V

A

B

Twin conductor, 100% screen, red.
18, 20 W/m (230 V).
DIN IEC 60800:2009 M2

Single conductor, wire screen, red.
20 W/m (230 V).
DIN IEC 60800:1992 C

A

B

B

Resistive heating cable
ECsafe 20T

Resistive heating cable
ECsnow

Fixing ECfast Metal 25 m pack; galvanized metal, fixings every 2,5 cm.

Regulator
EFIT

Moisture & temperature
sensor

Accessories

Thermostat
EFET

Thermostat
EFET

Thermostat
EFET

ECsafe 20T,
230 V

ECsnow 20T,
230 & 400 V program;
ECsnow 30T,
230 & 400 V program

EFIT 850

Ground sensor
for EFIT 850

PSU 24 V
for EFIT 850

EFET 330 (5…45 °C)

EFET 610

EFET 130

Twin conductor, 100% screen, UV stable, black.
20 W/m (230 V).
DIN IEC 60800:2009 M2

Twin conductor, 100% screen, FEP conductor insulation, UV stable,
black.
20 and 30 W/m (230/400 V).
DIN IEC 60800:2009 M2

Connection to Ground and Roof moisture and temp. sensor, max 4
sensors, 2 zones,
2x15 A, PSU 24 V, DIN rail

Ø93 x 98 mm, IP67, 15 m connection cable 4x1 mm²

Extra PSU for EFIT 850 with 3-4 sensors

5…45 °C, 16 A, IP20, with 3 m wire sensor,
DIN rail

-30…+50 °C, 10 A, IP44, with 3 m wire sensor,
on wall/pipe installation

5…45 °C, 16 A, IP30, with 3 m wire sensor,
room on wall installation

For additional information please refer to the Danfoss Catalogue.

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Application manual · Ground application. Ice & Snow Melting · VGHWD102 · ©Danfoss