Danfoss FED-IF, FED-FF Data sheet [fa]

Data sheet FEK sensors

Control of cooling circuit

Products

FEK-IF: with integrated sensor FEK-FF: with remote sensor

Ordering and
specifications

Application

The FEK sensor is installed in rooms which
have surplus heat due to internal or external
heat sources; i.e. only control of cooling circuit
is needed.
When the room temperature rises above the
set temperature the FEK sensor opens the
cooling valve.
FEK-IF as well as FEK-FF sensors can be

For cooling circuits in fancoils and induction
units use the FEK-FF with remote sensor.
The remote sensor can e.g. be placed below
the cabinet of the air inlet or on a separate
wall surface.
By placing the sensor in the air inlet a quicker
reaction time of the air temperature changes

is achieved.
used for chilled ceilings, fancoils and induc­tion units.

Type Code no. Sensor Capillary tube Setting range
FEK-IF 013G5465 Integrated sensor 5 m
FEK-FF 013G5464 Remote sensor 2 + 2 m

17-27 °C

Control of cooling circuit - chilled ceiling

FEK-IF

Cooling circuit

RA-C

Control of cooling circuit - fancoils and inductions units

Cooling circuit

FEK-FF

RA-C

CD-ST VD.33.S1.02. © Danfoss 06/99 1

Data sheet Climate controls: FEK sensors

FEK sensor design

Remote tempera­ture adjuster

Temperature setting

Cooling
adapter

Actuator

The FEK sensors are applied with RA-C
valves.

The FEK sensors are equipped with a reverse

Comfort temperature ~ 22 °C at Xp = 0 K

Remote sensor
(only FEK-FF)

device for the control of cooling circuits. With
the reverse device the valve in the cooling
circuit will open when the temperature rises
above the set temperature.

The FEK sensors have been developed for

valves via capillaries and adapters.
room cooling via water-based cooling sys­tems.

The scale shows the approximate set-point

offset from the comfort temperature which is
The FEK sensors are based on the self-acting
principle. The liquid-filled sensors control the

approximately 22° C at X

= 0 K.

p

2 VD.33.S1.02. © Danfoss 06/99 CD-ST

Data sheet Climate controls: FEK sensors

Temperature control
through cooling with FEK
sensor

Example

Control area of FEK sensor with RA-C valve

Xp = 0 K

Xp = 3 K

A setting in the blue temperature area means
that the setpoint of the cooling circuit is placed
below the comfort temperature. I.e. the valve
will open at a lower temperature than the
comfort temperature of appoximately 22 °C.
With a setting in the red temperature area the
setpoint of the cooling circuit is placed above
the comfort temperature. The valve in the
cooling circuit will open at a room temperature
above the comfort temperature of approxi­mately 22 °C.

Lowering comfort temperature with 4 °C.

Cooling with FEK thermostat

Waterflow,
cooling

Setpoint on knob

Waterflow, cooling
RA-C valve with presetting N

Limiting the set tempera­ture of FEK sensors

The knob is turned to lower the comfort tem­perature with 4 °C from 22 °C to approx.
18° C at X

As the set point temperature is at X
valve in the cooling circuit will not open before

= 0 K.

p

= 0 K the

p

the sensor temperature exceeds 18 °C.

The set temperature of the remote tempera­ture adjuster depends on the sensor type and
the valves, which are used with the sensors.

In the presetting N the RA-C valve works with
a P-band of maximum 3 K. This means that
the RA-C valve will be fully open and give
maximum flow to the cooling circuit at a sen­sor temperature of approx. 21 °C (set point:
18 °C + P-band: 3 K).

It is easy to limit or lock the set temperature
by means of the built-in locking/limiting de­vice.

Maximum limitation of temperature areaMinimum limitation of temperature area

CD-ST VD.33.S1.02. © Danfoss 06/99 3

Data sheet Climate controls: FEK sensors

Design

1. Cooling adapter

2. Neutral zone adjustment
knob

3. Reverse device

4. Adjustment bellow

5. Actuator

6. Capillary reel

7. Bellow

8. Remote temperature
adjuster

9. Remote temperature sensor
(only FEK-FF)

Dimensions

FEK-IF

FEK-FF

VD.33.S1.02. © Danfoss 06/99 CD-ST