© Danfoss | 2022.02 | 7
AQ37205364640601-010103
AFPA 2 / VFG 2(1) DN 15-250, VFG 22(1) DN 65-250
ENGLISH
Safety Notes
Prior to assembly and commissioning
to avoid injury of persons and damages
of the devices, it is absolutely necessary
to carefully read and observe these instructions.
Necessary assembly, start-up, and maintenance
work must be performed only by qualified,
trained and authorized personnel.
Prior to assembly and maintenance work on the
controller, the system must be:
- depressurized,
- cooled down,
- emptied and
- cleaned.
Please comply with the instructions of the
system manufacturer or system operator.
Definition of Application
The controller is used for differential pressure
control in bypass lines of water and water glycol
mixtures for heating, district heating and cooling
systems.
The technical data on the label plates determine
the use.
Scope of Delivery
❶
*) adapter 003G1780, accessory sold separately,
**) Impulse tube AF, accessory sold separately
Assembly
Admissible Installation Positions
❷
①
media temperatures up to 150 °C:
Can be installed in any positi on.
②
media temperatures > 150 °C.
Installation permitted only in horizontal
pipelines with the actuator oriented
downwards.
Installation Location and Installation
Scheme
❸
Bypass installation
The valve is closed without pressure
and is opening on rising differential
pressure
①
.
Valve Installation
❹
1. Install strainer
①
before the controller.
2. Rinse system prior to installing the valve.
3. Observe flow direction
②
on valve body.
Flanges
③
in the pipeline must be in
parallel position and sealing surfaces
must be clean and without any damage.
4. Install valve.
5. Tighten screws crosswise in 3 steps up to the
max. torque.
Actuator Installation
❺
The actuator stem must be screwed into
the valve stem. Spring on the pressure
actuator is factory adjusted (stressed).
1. Remove the spindle protection cup and
release the valve spindle by removing the
nut, washer and cardboard tube.
2. Align the actuator stem with the valve stem,
connect both stems and turn gently the
whole pressure actuator clockwise with both
hands, until the stems are fully connected
(valve stem fully screwed into the actuator
stem).
3. Release spring (unstress) and release the
uninon nut by pulling out the blocking
spring.
4. Tight the union nut by hand or with wrench
key using minimal force
5. Release the pressure actuator by turning it
counter clockwise for approximately half a
turn.
6. Observe the position of impulse tubes
connection to the valve and align the
actuator accordingly.
7. Hold the actuator in the position and tight
the union nut to the valve with 100- 120 Nm
torque.
Impulse Tube mounting
❻
• Which impulse tubes to use?
The impulse tube set AF (2×)
❻①
can be
used: Order No.:
003G1391
or use the following pipes:
Steel /
Stainless steel
Ø 10×1
ISO 1127 D3/T3
Copper
Ø 10×1
Cu-DHP R200
EN12449
•
The impulse tube
③
can be connected
directly to the valve
④
or
to the pipeline
⑤
.
Connection to the valve
❼
1. Remove plug
①
at the valve.
2. Screw in threaded joint G 1/4
②
with copper
seal, Torque 40 Nm.
- or -
Connection to the Pipeline
❽①
No connection downwards/upwards
②
, could
bring dirt/air into an impulse tube.
1. Cut pipe in rectangular sections
③
and
deburr.
2. For copper pipe:
insert sockets
④
on both sides.
3. Verify the correct position of the cutting
ring
⑤
.
4. Press impulse tube
⑥
into the threaded joint
up to its stop.
5. Tighten union nut
⑦
Torque 40 Nm.
When installing seal pots
❽⑧
, please
observe the Installati on Instructions
for the seal pots.
Insulation
❾
For media temperatures up to 120 °C the
pressure actua tor may be insulated
①
.
Dismounting
❿
Danger
Danger of injury by hot water
Prior to dismounting depres surize system or
use shut off valves on the impulse tubes!
①
Carry out dismounting in following steps:
②
1. Fasten pressure actuator with the safety
bands to the fixed points in surroundings
2. Before releasing the actuator, fully release
the union nut
3. Hold the pressure actuator with both
hands, and release it by turning it counter
clockwise ~30 turns. During turning, control
the actuator weight all the time to prevent
unexpected fall of detached actuator.
4. Carefully remove the actuator from the valve.
Before installing actuator back to the valve,
setting spring must be fully released again.
Leak and Pressure Test
⓫
Observe max.
permitted pressure, see below.
The pressure behind the valve
②
must not
exceed the pressure before the valve
①
.
Observe nominal pressure
⑤
of the valve.
Caution:
The valve is closed without pressure and it
opens on rising pressure before the valve.
Prior to pressure tests
, it is
absolutely
necessary
to remove the impulse tube at the valve
④
.
Close connections with plugs G ¼ ISO 228.
Max. pressure [bar] with connected impulse tube:
AFPA 2
cm
2
32
80
160
320
640
bar
16
5
2.5
1.3
0.35
Max. test pressure with disconnected impulse
tube must not exceed the plant testing pressure
and must always be lower than 1.5 × PN.
Non-compliance may cause damages at the
controller
③
.
Filling the System, Start-up
⓬
The pressure
②
behind the valve
must not exceed the pressure
①
before
the valve.
Non-compliance may cause damages at the
controller
③
.
1. Open shut-off devices that are possibly
available at the impulse tubes
④
.
2. Slowly open valves in the system.
3. Slowly open shut-off device
⑤
.
4. Slowly open shut-off device
⑥
.
Putting out of Operation
1. Slowly close shut-off device
⑤
.
2. Slowly close shut-off device
⑥
.
Setpoint Adjustment
⓭
1. Set-point range see rating plate
①
2. Start-up of system, see section
⓬
.
3. Start pump
②
4. Observe pressure indicator
③
5. Slightly close fitting
④
behind the pump (in
flow direction) so that the pressure
③
is rising.
6. Adjustment of the differential pressure over
the valve:
• Turning to the right
⑥
reduces the set-point
(unstressing the spring - tension spring)
• Turning to the left
⑦
increases the set-point
(stressing the spring)
7. If the required pressure
③
cannot be set,
further close the fitting
④
.
8. The set-point adjuster
⑧
may be sealed.
9. Release the not yet used pointer
⑨
, move it
to the set position and fix it with the screw to
mark setting position
Dimensions
⓮
Flanges: connection dimensi ons acc. to
DIN 2501, seal form C
