Danfoss PCVD User manual

© Danfoss | 2016.05 VI.JA.C3.5B | 1
Instructions
Pilot-controlled Pressure Reducer PCVD,
Pilot-controlled Safety Shut-off-valve PCVSAD
DN 100-250,PN16/25
English Page 2
Einbau-, Bedienungsanleitung
Hilfsgesteuerter Druckminderer PCVD,
Hilfsgesteuertes Sicherheitsabsperrventil (SAV) PCVSAD
DN 100-250,PN16/25
Deutsch Seite 16

Instructions PCVD, PCVSAD
2 | © Danfoss | 2016.05 VI.JA.C3.5B
1 Safety Notes .......................................................3
2 Definition of Application .............................3
3 Description...........................................................4
3.1 Construction ......................................................... 4
3.2 Mode of Operation ............................................ 4
4 Technical Data ................................................... 4
5 Scope of Delivery.............................................. 5
6 Assembly .............................................................. 6
6.1 Prior to Assembly ................................................ 6
6.2 Installation Position ........................................... 6
6.3 When Installing observe ................................... 6
6.4 Impulse Tube Installation ................................. 6
6.5 Insulation ............................................................... 6
6.6 Installation Scheme ............................................ 7
6.7 Assembly Drawings, Dimensions ................. 8
7 Start-up................................................................10
7.1 Required Static Pressure, Pressure
Difference ............................................................10
7.2 Leak and Pressure Tests ..................................10
7.3 Filling the System ..............................................10
7.4 Start-up .................................................................10
7.5 Putting out of Operation ...............................10
7.6 Adjustment of the Setpoint .......................... 11
7.7 Sealing .................................................................. 11
7.8 Function Test ...................................................... 11
8 Trouble Shooting ...........................................12
8.1 Fault, Possible Cause, Remedy ..................... 12
8.2 Diaphragm Break of
the Controller SAVD ......................................... 12
9 Replacement of Valve,
Actuator, Trim ..................................................13
9.1 Dismounting and Mounting Actuator
and Valve of the Valve Unit ........................... 13
9.2 Replacement of Trim Valve VFG 2 ............... 14
9.3 Dismounting,
Mounting Actuator AVD, SAVD ....................14
9.4 Replacement of
Trim Valve AVD, SAVD ...................................... 15
Table of Contents

Instructions PCVD, PCVSAD
© Danfoss | 2016.05 | 3
VI.JA.C3.5B
MAINTENANCE
FREE
1 Safety Notes
2 Definition of
Application
The controller is used for flow rate limitation of
water for heating, district heating and cooling
systems.
The admissible medium temperatures depend
on the design and comprise 5-150 °C,
5-200 °C.
The technical data on the rating plates deter-
mine the use.
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.

Instructions PCVD, PCVSAD
4 | © Danfoss | 2016.05 VI.JA.C3.5B
Pilot controller AVDThrottling element
Valve Unit PCV-VFG2
Throttling valve
T
hrottling valve
only DN150-250
3 Description 3.1 Construction
3.2 Mode of Operation
The control unit consists of the PCV-VFG2 valve
unit, installed in the main pipe, and the pressure
controller AVD or safety shut-off-valve SAVD
installed as pilot controller in the bypass. In the
bypass line, a throttle element is installed in front
of the pilot controllers.
As a pressure reducer, the controller keeps the
pressure behind the controller unit in accordance
with the preset setpoint on a constant level.
As a safety shut-off valve, the controller
guarantees that the pressure is not exceeded. If
the controller diaphragm is damaged, the valve
is closed via the second diaphragm.
The valve and the pilot valves are pressure-
balanced.
The setpoint for the pressure is adjusted by
pre-stressing the setpoint spring of the pilot
controller.
Valve unit PCV-VFG 2
The valve unit in the main pipe is opening on
rising pressure. The pilot controllers in the
bypass line are closing on rising pressure.
In case of small flow rates, the valve in the main
pipe remains closed through the pressure spring
in the actuator of the valve unit. The pressure is
exclusively controlled by the pilot controller.
If the flow rate in the bypass is increased, the
pressure in the throttle element (Venturi nozzle)
decreases.
The reduced pressure acts through an impulse
tube upon the lower chamber of the actuator
of the valve unit. The main valve is thus opened
shock-free and continuously.
If the flow rate is reduced, the pressure in the
throttle element raises and the main valve closes.
This sequential switching guarantees an
operation free of vibrations and a small control
deviation over a wide positioning range.
4 Technical Data
Technical data, see rating plates and the PCV
data sheet.

Instructions PCVD, PCVSAD
© Danfoss | 2016.05 | 5
VI.JA.C3.5B
5 Scope of Delivery
DN 100-125
Assembly kit valve unit PCV-VFG 2 Pilot controller AVD DN 25
AVD
Cu pipe Ø 6 × 1 × 1500 mm
Cu pipe Ø 10 × 1 × 3000 mm
Throttling element
DN 150-250
Assembly kit valve unit PCV-VFG 2 Pilot controller AVD DN 40
Throttling element
Cu pipe Ø 6 × 1 × 1500 mm
Cu pipe Ø 10 × 1 × 3000 mm
SAVD
AVD SAVD

Instructions PCVD, PCVSAD
6 | © Danfoss | 2016.05 VI.JA.C3.5B
pin only
weld
do NOT
weld
1
2
6 Assembly 6.1 Prior to Assembly:
Depressurized system before
any assembly work !
CAUTION!
• Clean pipeline system.
• Install strainer in front of the controller.
• Install shut-off units in front of and behind
the controller.
6.2 Installation Position
• Installation is only permitted in horizontal
pipelines with the actuators hanging in a
downward position.
6.3 When installing observe:
• Observe direction of flow.
• Design with welded ends:
• Loads on the valve body and the throttle
element by the pipes are not permitted.
6.4 Impulse Tube Installation
1. See installation scheme, section 6.6.
2. For CU pipes Ø 10 × 0.8, insert sockets 1on
both sides.
3. Care for correct position of the cutting
rings 2.
6.5 Insulation
The diaphragm actuators must not be insulated
when insulating system parts.
4. Press impulse tube into the threaded fitting
up to its stop.
5. Tighten union nut, torque 40 Nm
6. Dismount again and check the position of
the cutting rings.

Instructions PCVD, PCVSAD
© Danfoss | 2016.05 | 7
VI.JA.C3.5B
Shu
t-off valve
CU pipe Ø 6 × 1
Valve unit PCV - VFG 2
Throttle valve
Throttling element
Throttle valve
(DN 150-250 only)
CU pipe Ø 10 × 1
Pilot controller AVD
lay impulse tube during mounting
D
o not install a
shut
-off valve her.
But if you do s
o,
it
is absolutely
necessar
y
to
secure against
unauthorized
closing
.
CU pipe Ø 6 × 1
Valve unit PCV - VFG
Throttle valve
Throttling element
Throttle valve
(DN 150-250 only)
CU pipe Ø 10 × 1
Pilot controller SAVD
lay impulse tube during mounting
6.6 Installation Scheme
Installation in the Return Line
Installation in the Supply Line

Instructions PCVD, PCVSAD
8 | © Danfoss | 2016.05 VI.JA.C3.5B
Dismount impulse tube
- Unscrew threaded fittings at the
valve and at the actuator
- Close opening at the valve
with a stopper (see assembly kit
order No. 003G1599)
Cu pipe Ø 10 × 1
Lay when assembling.
Install impulse tubes
laterally because of dir
t
Cu
pipe Ø 6 × 1,
when laying
,
use the assembly
kit
order No
. 003G1599
Valve unit PCV - VFG 2
DN 25: pipe Ø 33,7 × 3,2
Ma
terial: ST 35.8
(not par
t of the delivery)
Pilot controller AVD
DN 25 SW 50
Throttling element
these parts are
not in the scope of delivery
6.7 Assembly Drawings, Dimensions
DN 100-125

Instructions PCVD, PCVSAD
© Danfoss | 2016.05 | 9
VI.JA.C3.5B
Dismount impulse tube
- Unscrew threaded fittings at the
valve and at the actuator
- Close opening at the valve with a
stopper (see assembly kit order
No. 003G1599)
Cu pipe Ø 10 × 1
Lay when assembling.
Install impulse tubes
laterally because of dirt
Cu
pipe Ø 6 × 1,
when laying
,
use the assembly
kit
order No
.003G1599
DN 40: pipe Ø 48,3 × 3,2
Ma
terial: ST 35.8
(not par
t of the delivery)
these parts are
not in the scope of delivery
DN 150-250
Dimensions
Nominal diameter DN 100 125 150 200 250
L1
mm
350 400 480 600 730
H1 530 530 619 647 697
H2 -174 229 254
D2 263 380
D1 250 350 385 500
B200 210 310 336 412
A ≥ 290 320 350 410

Instructions PCVD, PCVSAD
10 | © Danfoss | 2016.05 VI.JA.C3.5B
1
p2 p1
7
2
3
5
4
6
8
910
7 Start-up 7.1 Required Static Pressure, Pressure
Difference
For a proper functioning, a minimum pressure
difference of p1 − p2 ≥ 0.5 bar is required.
The static pressure p1 in front of the controller
must not fall below 1.5 bar (excess pressure).
Non-observance may lead to cavitation and
damages in the throttling element 1.
7.3 Filling the System
Note:
The controller 6is closed when no pressure is
applied and only opens with a defined flow in the
bypass.
The pilot controllers 7are closing on rising pressure.
7.2 Leak and Pressure Tests
To avoid too high pressures at
the diaphragm actuators, the
following should be observed
prior to any pressure tests:
Actuator of valve unit:
The admissible operating excess pressure in the
actuator 2is 15 bar 1). For higher pressures, you
must:
• Remove the impulse tube 3
The admissible operating excess pressure in the
actuator 4is 25 bar 1). For higher pressures, you
must:
• Remove the impulse tubes 5at the actuator
and close the connections with a stopper
• Prior to any leak or pressure test, the
instructions in section 7.3 must be complied
with.
1) Pre-condition: Same pressure on both sides of the diaphragm.
If the pressure load is one-sided, the (+)diaphragm chamber
may have an excess pressure of 1 bar in comparison to the (-)
diaphragm chamber.
Procedure
1. Open shut-off valves 8that possibly exist in
the impulse tubes.
2. Slowly open shut-off units first in the return
flow 9and then in the supply flow 10.
7.4 Start-up
During starting-up the filled system, open the
units in the same sequence as described in
section 7.3.
7.5 Putting out of operation
When putting the system out of operation, first
close the shut-off units in the supply flow and
then those of the return flow.