Danfoss CET2000B-RF + RX1-S + CS2 User manual

CET2000B-RF + RX1-S + CS2
Wireless Electronic Hot Water Cylinder Thermostat
User Guide
Danfoss Heating

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For a large print version of these instructions
please call Marketing on 0845 121 7400.
Danfoss can accept no responsibility for possible errors in catalogues, brochures, and other
printed material. All trademarks in this material are property of the respective companies.
Danfoss and the Danfoss logotype are trademarks of Danfoss A/S. All rights reserved.
Hearby, Danfoss A/S declares that the radio equipment type CET2000B-RF + RX1-S is in
compliance with directive 2014/53/EU.
The full text of the EU declaration of conformity is available at the following internet
address, http://heating.danfoss.co.uk/xdoccat/14_CATC-J_MNU17497125_SIT313.html

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Thank you for buying a Danfoss product

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What is a cylinder thermostat?
... an explanation for householders
A cylinder thermostat switches on and o the heat supply
from the boiler to the hot-water cylinder. It works by sensing
the temperature of the water inside the cylinder, switching
on the water heating when the temperature falls below
the thermostat setting, and switching it o once this set
temperature has been reached.
Turning a cylinder thermostat to a higher setting will not make
the water heat up any faster. How quickly the water heats up
depends on the design of the heating system, for example, the

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size of boiler and the heat exchanger inside the cylinder.
The water heating will not work if a time switch or programmer
has switched it o. And the cylinder thermostat will not always
switch the boiler o, because the boiler sometimes needs to heat
the radiators.
Cylinder thermostats or cylinder sensors are tted directly to the
surface of the cylinder. The cylinder thermostat (or temperature
controller when used with sensor) will have a temperature scale,
and it should be set at between 60°C and 65°C, then left to do its
job. This temperature is high enough to kill o harmful bacteria
in the water, but raising the temperature of the stored hot water
any higher will result in wasted energy and increase the risk of
scalding.
If you have a boiler control thermostat, it should always be set
to a higher temperature than that of the cylinder thermostat. In
most boilers, a single boiler thermostat controls the temperature
of water sent to both the cylinder and radiators, although in
some there are two separate boiler thermostats.

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Display
The LCD displays actual cylinder water temperature until the
Λ or V button is pressed more than once. To activate the unit’s
backlight press the Λ or V button once, if no further buttons are
pressed the backlight will remain on for 6 seconds.
Temperature

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Flame: shows when heating output is on
Standby: shows when unit is manual set to standby
Battery: ashes when battery is low (battery units only)
Padlock: indicates keyboard lock has been set at
installation
Antenna: indicates a paired link is active between the
thermostat and receiver
External Sensor Alarm:
E5 = Sensor short circuit
E6 = Sensor open circuit / missing

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Setting the temperature
Press either the Λ or V buttons, the product backlight will come
on.
Press either the Λ or V button again within 6 seconds, the display
will ash with the current set temperature. While the display is
ashing press the Λ arrow to increase the set temperature to the
required setting or the V arrow to decrease the set temperature.
If no buttons are pressed the display will return to actual
temperature after 4 seconds and the backlight will go out after
6 seconds.
Please Note: In order to reduce the risk of Legionella infection, it is
recommended that water be stored at not less than 60°C.

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Thermostat status
A ame symbol will be lit whenever the thermostat is calling for
heat.
Thermostat standby
To place the thermostat into standby (o), press the V arrow
twice to enter the temperature setting mode. Press and hold the
V arrow until the set temperature disappears and the standby
symbol appears.
When in standby the thermostat will have no control of the Hot
Water Cylinder Temperature.
To exit standby press and hold the Λ arrow until the required set
temperature is ashing on the display.

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Manual Override
During normal Thermostat operation the CH button on the
receiver will light when the device is calling for heat. Should
communication between the thermostat and receiver fail,
manual override is possible by pressing the CH button once;
the hot water system will remain on during manual override as
indicated by the lit CH button. Press CH button again to cancel
manual override. When communication is re-established the
thermostat and receiver will return to automatic control.
Warning – Leaving the system in manual override will result in
the boiler heating continually and will result in higher energy
usage.