Danfoss FED - IF, FED - FF Data sheet

Data Sheet

Cooling Circuit

Heating Circuit /
Radiator

RA-C

RA-C or
RA2000

FED-IF

Emitting Unit

RA-C

RA-C or
FED-FF

Remote

Cooling

Heating

Circuit

FED
Thermostatic Controller for
Cooling & Heating Circuits

Application:

Ordering Information:

FED thermostatic controllers are used in
hydronic applications where both a
cooling and a heating circuit are
regulated by one controller. The FED is

FED - IF

available in two versions, FED-IF with
integrated room air sensor, and FED-FF
with a remote air sensor. Both the FED-IF
and the FED-FF are low cost methods of
controlling chilled ceilings, radiators, fan
coils, and induction units. In situations

FED - FF

requiring a faster response time, the FED
FF’s remote sensor can be placed
directly in the air stream providing an
option of mounting the dial directly on a
cabinet.

Code No.

013G5463

013G5462

Operator

FED-IF Integrated

Sensor

RemoteFED-FF

Capillary Tube

12 + 36ft

(4 + 11 m)

6 + 6 + 6 ft

(2 + 2 + 2m)

Setting Range

63 - 80 ° F

(17 - 27 ° C)

*The cooling adapter is recommended to be mounted to the RA-C series of valves,
while the heating adapter can be mounted to either the RA2000 or RA-C series of
valves.

Application:

Control of chilled

ceiling and

radiator

VD33T222 © Danfoss 03/14

Control of

fancoils and

induction units

1

Data Sheet FED Thermostatic Controller for Cooling & Heating Circuits

Cooling Actuator &

Valve

Heating Actuator &

Valve

Induction Unit

FED Sensor Design:

The FED sensor is equipped with a
heating adapter and cooling adapter
(reverse device). Both are connected via
capillary tubes to the remote
temperature adjuster (dial). The reverse
device will open the valve in the cooling
circuit as the temperature rises above
the set point temperature. Similarly, the
heating adapter will open the valve in
the heating circuit when the
temperature falls below the set point
temperature. With the FED-FF model an
additional capillary tube from the dial
connects to a remote temperature
sensor.

Serial Coupling

A unique ability with the FED thermostatic operator is the interchangeability of the
cooling and heating adapters. Out of the box, the FED sensor is assembled with the
cooling adapter closest to the dial and the heating adapter further away. Yet this
order can easily be exchanged and the FED sensor will still control in the right
sequence. The interchange of valve adapters expands the possibilities of the dial
placement.

Temperature Limitation

Incorporated into the dial is the unique ability to limit the rotation of the dial
providing minimum and maximum limitation of the temperature settings. To set
this limitation the front cover of the dial is removed exposing the setting tabs.

Temperature Setting:

When the dial is set to the center as
shown in the illustration above, the
thermostatic operator will maintain a
comfort temperature of around 72°F
(22°C). By rotating the dial to the red or
blue side, the comfort temperature will
be shifted as a result. In the state where
room temperature is satised, neither
the cooling nor the heating circuit
would be opened. If the temperature
rises above the set point temperature,
the reverse device will cause the valve

for the cooling circuit to open. Likewise,
if the temperature falls below the set
point the cooling circuit will close and
the heating circuit valve will open.

Built into the cooling adapter is a neutral
zone (also known as a dead band) to
ensure that both the heating and
cooling valves do not operate
simultaneously. The neutral zone has a
settable range of 0.9°-4.5° (0.5°-2.5°C),
and can be adjusted depending on the

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VD33T222 © Danfoss 03/14

Data Sheet FED Thermostatic Controller for Cooling & Heating Circuits

°F

72

gpm

66

A lower set temperature

Cooling

Heating

Neutral zone
Max.

Max.

71

°

69

63

58

gpm

66

Set Temperature

Proportional band

Temperature Setting
(Cont.):

system design and requirements by
rotating the knob located on the cooling
adapter with a set of pliers. The know
when turned clockwise will increase the
dead band and if turned counter­clockwise will decrease it. The factory
setting of the neutral zone is marked on
the knob recess.

Example - Setting the Dial

For this example the dial is turned
clockwise to the blue side of the
settings, lowering the set comfort
temperature from 72°F (22°C) to

Shift of Temperature

approximately 66°F (19°C). Additionally
the neutral zone (dead band) has been
preset to 3°F. As a result, the set
temperature of 66°F (19°C) plus the
neutral zone of 3°F produces a range of
63-69°F where neither heating nor
cooling occurs.

P-Band

(19)

(22)

°C

A contributing factor to the ability of the
FED’s workable temperature range deals
with the concept known as the
proportional band or P-band. This
concept applies dierently than the
neutral zone. The P-band correlates to
the valve’s ability to provide the

(Dead band)

appropriate amount of ow that meets
the demand of the terminal unit (chilled
ceilings, radiators, fan coils, or induction
units). The proper ow can determine
the controller’s ability to maintain the
set temperature. The shaded region

(14) (17) (21)

(22)

F

°C

seen in the gure below relates the
ambient temperature and the required
ow to bring the temperature back to
the set temperature. When the
temperature hits maximum as seen in
the graph, the valve is fully open based
upon its setting. In the adjustment of
the valve’s ow, as seen with the RA-C’s
ow pre-settings of 1-2-3 & N, the
maximum ow of the terminal unit
should be matched to the pre-setting
capacities of the RA-C valve. In properly
setting the valve refer to the RA-C
capacity diagrams and consider a
P-band based upon load requirements
of 5.4°F (3°C) from the set temperature.

VD33T222 © Danfoss 03/14

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Data Sheet FED Thermostatic Controller for Cooling & Heating Circuits

Design:

Dimensions:

1. Heat adapter

2. Actuator

3. Adjustment bellows

4. Capillary reel (only FED-IF)

5. Cooling adapter

6. Neutral zone adjustment knob

7. Reverse device

FED -IF

FED -FF

8. Adjustment bellow

9. Actuator

10. Capillary reel

11. Remote temperature adjuster

12. Bellows

13. Remote temperature sensor
(only FED-FF)

Danfoss can accept no responsibility for possible errors in printed materials and reserves the right to alter its products without notice. All trademarks
in this material are property of the respective companies. Danfoss and Danfoss logotype are trademarks of Danfoss A/S. All rights reserved.

Danfoss Inc.

Toronto, ON
Toll Free: 866-375-HVAC (4822)
Tel.: [phone], Fax: [phone]
www.na.heating.danfoss.com

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VD33T222 © Danfoss 03/14

Danfoss Inc.

Baltimore, MD
Toll Free: 866-375-HVAC (4822)
Tel.: [phone], Fax: [phone]
www.na.heating.danfoss.com