Danfoss EFIT 550 User manual

EFIT 550
User Guide
and Installation Manual
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MAKING MODERN LIVING POSSIBLE
Danfoss Heating
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Thank you for buying a Danfoss product. With this purchase
you have obtained a product of the highest quality, designed
to give long lasting comfort at a minimum of environmental
impact.

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Contents
User Guide
1. Basics ................................................................................................4
1.1 Safety instructions.................................................................4
1.2 Functional overview .............................................................5
1.3 Temperature settings ..........................................................5
1.4 Changing Battery...................................................................6
1.5 Operating the child lock......................................................6
1.6 Switching the thermostat on and off .............................7
2. Advanced........................................................................................7
2.1 Optional Settings...................................................................8
2.2 Troubleshooting ................................................................. 11
2.3 Uninstalling Product.......................................................... 11
2.4 Specifications ....................................................................... 12
Installation manual ..............................................................
1.0 Installation overview ............................................................. 14
1.1 Safety instructions............................................................. 14
1.2 Installation guidelines...................................................... 14
2.0 System overview....................................................................... 15
2.1 Three different sensor configurations........................ 15
2.2 Network................................................................................. 16
3.0 Functional overview............................................................... 16
4.0 Installation - step by step..................................................... 17
4.1 Preparations and guidelines.......................................... 17
4.2 Dismantling the thermostat .......................................... 17
4.3 Connecting cables............................................................. 19
4.4 Mounting and reassembling the thermostat.......... 20
4.5 Activating the thermostat .............................................. 20
4.6 Configuring basic settings.............................................. 20
5.0 Optional settings..................................................................... 24
5.1 Network setup .................................................................... 24
6.0 Trouble-Shooting Diagram ................................................. 26
7.0 Factory Settings ....................................................................... 27
8.0 Warranty...................................................................................... 28

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1.0 Basics
The EFIT 550 thermostat controls electrical floor heating•
elements using a built-in and/or external temperature
sensor.
The EFIT 550’s adaptive function automatically optimises•
the unit for the room within a few days after installation
and continuously collects updated room data. This means
improved performance (with compensation for e.g. sudden
temperature drops in the room) and precise timing so the
selected temperature is achieved at exactly the right time.
The unit can be operated with or without the built-in timer.•
When the timer is used, the unit can automatically switch
between the set comfort temperature and economy tem-
perature at specific times of day. To use the timer, you must
first set the day and time and then set the timer.
1.1 Safety instructions
Do not cover the thermostat, e.g. by hanging towels or•
similar items in front of it! This will impair the unit’s ability
to sense and adjust the room temperature correctly.
This does not apply if the thermostat is configured to use a•
floor sensor only.
Do not spill liquids of any kind into the thermostat.•
Do not open, disassemble, or tamper with the thermostat•
in any way.
If the thermostat is installed in a place frequented by small•
children, use the child lock.
User guide

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1.2 Functional Overview
The thermostat is operated by using the button as follows:
Turning clockwise or counter-clockwise to raise or lower
values, e.g. when setting the temperature
Pressing briefly to activate or deactivate the timer or
confirm a setting during configuration
Pressing and holding for a number of seconds to access
various settings
User guide
Timer on
Frost
protection
on
Display
Hour display
Clock setting
active
Button
Child lock on
Temperature
below set
value
Degree symbol
Weekday
display
Timer setting
active

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User guide
1.3 Temperature Setting
Operation without timer:
The hour display appears as an unbroken ring with a blink-•
ing dot indicating the current time (if set).
Raise or lower the temperature.
The set temperature appears on the display.•
The system maintains the set temperature 24 hours a day.•
If the thermostat uses a floor sensor only, the display•
shows the set temperature on a scale from 1 to 10.
If you lower the temperature to +5 °C,• appears on the
display.
The thermostat maintains a temperature of +5 °C in the•
room for frost protection.
If you lower the temperature below +5 °C, the thermostat•
switches off.
“OFF” appears on the display.•
1.4 Changing Battery
The backup battery saves clock settings when the mains•
supply is off.
The battery recharges automatically when the mains sup-•
ply is on and does not normally need to be changed.

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User guide
1.5 Operating the child lock
Press and hold the button.
While holding, turn steadily counter-clockwise,
until “CODE” appears on the display.
Turn clockwise to select “0033”.
Press to confirm. appears on the display.
The child lock is on. The thermostat cannot be operated•
using the button except to switch off the child lock.
The child lock can be switched off using the same proce-•
dure as for switching it on.
1.6 Switching the thermostat on and off
The thermostat can only be switched off if the timer is off.
The thermostat is on by default.
If you lower the temperature below +5 °C, the
thermostat switches off. Turn vigorously counter-clock-
wise to achieve this. “OFF” appears on the display.
If you raise the temperature to +5 °C or above, the
thermostat switches on again.

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User guide
2.0 Advanced
2.0.1 Switching the timer on and off
The timer is switched on and off by pressing the button.
When the timer is on:
• appears on the display.
The hour display shows the set comfort temperature peri-•
ods for the current day as black segments of dots.
The current day is shown on the weekday display.•
The system automatically switches between comfort and•
economy temperatures at the preset times of day.
The economy temperature never appears on the alpha-•
numeric display. The display consistently shows the set
comfort temperature, even during economy tempera-
ture periods.
When the timer is off:
The hour display appears as an unbroken ring with a blink-•
ing dot indicating the current time (if set).
The system maintains the set temperature 24 hours a day.•
Note:
The thermostat can only be switched off if the timer is off.•

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User guide
2.1 Optional Settings
2.1.1 Setting the time and weekday
Press and hold for 3 seconds. appears on the display.
Set the correct time.
A small dot on the hour display shows the currently set•
time.
When the set time passes 0:00 in either direction, the•
weekday display changes to the next or previous day
(depending on which direction the button is being
turned).
Press to confirm. disappears from the display.
2.1.2 Setting the timer
Press and hold for 6 seconds. appears on the display.
You can now program when the system should switch•
from comfort temperature to economy temperature and
vice versa.

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User guide
Select the weekday where you want the program to
start.
Press to confirm.
Set the starting time of the first comfort temperature
period.
Press to confirm.
Set the duration of the first comfort temperature period.
The duration is shown as a segment of black dots on the•
hour display.
Press to confirm.

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User guide
You have now defined the starting time, duration, and•
ending time of the first comfort temperature period.
Repeat as required to define subsequent comfort tempera-•
ture periods.
When the set time passes 0:00 in either direction, the•
weekday display changes to the next or previous day
(depending on which direction the button is being
turned). In this way it is possible to program an entire
week with different comfort and economy temperatures
for each day.
The intervals between the comfort temperature periods•
become economy temperature periods.
Press and hold for 3 seconds. disappears from the
display.
The display returns to normal.•
2.1.4 Setting minimum floor temperature
(This only applies if the thermostat is configured to use a
room and floor sensor.)
Press and hold for 9 seconds. “MFt” (Minimum Floor
Temperature) appears on the display.

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User guide
Set the minimum floor temperature.
Press to confirm. The display returns to normal.
The floor temperature is kept above the set lower limit.•
2.2 Troubleshooting
In case of an error, the hour display starts flashing and the•
weekday display indicates an error code from 2 to 7.
Refer to the description of error messages in section 6 of•
the Installation Manual.
If the system does not function correctly, call a qualified•
electrician.
2.3 Uninstalling Product
The product should only be uninstalled by a qualified•
electrician.

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User guide
2.4 Specifications
Temperature range: +5 to +35 °C or OFF
Floor temperature limit: +20 to +50 °C
Operation voltage: 180-250 VAC, 50/60 Hz
Resistive load: 230 V ~ 16A /3680W
Inductive load: cosϕ0,3 = Max. 1A
Power consumption: < 500 mW
Battery back-up: 100 hours
Economy set-back: 0 to -30 °C
Offset: -5.5 to +5.5 °C
IP class: IP30
Sensing unit NTC 15 kOhm AT 25 °C

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Installation manual
1.0 Installation overview
1.1 Safety instructions
Make sure the mains supply to the thermostat is OFF before•
installation. If the thermostat is installed in a network, the
mains supply to ALL thermostats in the network must be off!
As the EFIT 550 is not equipped with an earth terminal, the•
earthing screen of the heating cable and the earthing wire
from the mains supply must be connected to the earth
terminal in the surface mounted box or recessed metal box.
Do NOT use the EFIT 550 without a floor sensor when•
the heating element is installed under flooring with high
thermal resistance.
The thermostat must not be exposed to moisture, water,•
and excessive heat.

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Installation manual
1.2 Installation guidelines
Dismantle the thermostat before installation and observe•
the following guidelines:
Place the EFIT 550 at a suitable height on the wall.
In wet rooms, the thermostat should be installed
on an even surface according to local building
regulations.
Place the thermostat at least 50 cm from windows/
doors that will be left open occasionally.
Do not place the thermostat on a wall where it will
be exposed to direct sunlight.
Do not place the thermostat on the inner side of a
wall facing the outside.
Connect all cables to the terminals.•
Switch on the mains supply.•
Activate and configure the thermostat.•

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2.0 System overview
2.1 Three different sensor configurations
FS: Floor sensor (comfort heating)
Suitable for floor heating in e.g. bathrooms. The built-in•
room sensor is not used.
Comfort heating should be used only to supplement a•
regular room heating system.
RS: Room sensor (total heating)
Suitable for control of room temperature in e.g. living•
rooms. Unsuitable for wet rooms.
The thermostat must be mounted in the same room as the•
heating elements.
RFS: Room and floor sensor (total heating)
Suitable for control of room and floor temperature in e.g.•
living rooms. Unsuitable for wet rooms.
The floor sensor monitors the floor temperature, limiting•
heating element temperature to avoid risk of fire and to
protect flooring from excessive temperatures.
The maximum floor temperature must be set (see section•
4.6 below). It is also possible to set the minimum floor
temperature (see section 2.1.4 of the User guide).
The thermostat must be mounted in the same room as the•
floor sensor and heating elements.
2.2 Network
Up to 32 thermostats can be linked in a network.•
See section 5.1.
Installation manual

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3.0 Functional overview
The thermostat is programmed by pressing and holding the
button as follows:
Seconds held Function accessed Notes
3 Time and weekday
setting
6 Timer setting
9 Minimum floor
temperature set-
ting
Only when
configured to
use room and
floor sensor
12 Basic settings
Installation manual
Mounting
screws
Button
Release tab Frame
Front cover
Display

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4.0 Installation - step by step
4.1 Preparations and guidelines
All necessary cables should be routed to the intended•
installation point.
The thermostat is designed for installation in a surface•
mounted box or recessed box with the correct dimensions.
Read and observe the guidelines set forth in section 1.1•
and 1.2.
4.2 Dismantling the thermostat
Push down the release tab.•
Carefully detach the front cover.•
Remove the two screws.•
Installation manual
Release tab
Screws

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Carefully detach the display module. The module must be•
pulled straight out to avoid damaging the 8-pin connector
plug on the back of the module!
Frame
Carefully detach the frame.•
4.3 Connecting cables
Connect the cables as shown below.•
Devireg™ 550
Mains supply
180-250 V
50/60 Hz
Heating element
Max. load 16 Amp.
Network
connection
EFIT 550 ONLY
NTC sensor
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Connect wires in heating element and mains supply cables•
correctly!
Important! Connect the heating cable screen and the•
mains supply earthing wire to the mounting box earthing
terminal.
4.4 Mounting and reassembling the thermostat
Screw holes
Mount the base plate on the wall.•
Make sure the base plate cannot be moved.•
Install the frame, display module, and front cover in the•
reverse order of disassembly.
Installation manual