Danfoss Pilot-controlled PCVQ User manual

Instructions
Pilot-controlled PCVQ
DN 100 - DN 250
PN 16 / PN 25
73696700 DH-SMT/SI VI.JA.G2.02 © Danfoss 11/2006 1
Table of Contents
1 Safety Notes ...................................................... 2
2 Definition of Application ............................ 2
3 Description .......................................................... 2
3.1 Construction ......................................................... 2
3.2 Mode of Operation ........................................... 2
4 Technical Data .................................................. 3
5 Scope of Delivery ............................................. 3
6 Assembly ............................................................. 4
6.1 Prior to Assembly ............................................... 4
6.2 Installation Position,
Installation Place ................................................ 4
6.3 When Installaling observe ............................. 4
6.4 Impulse Tube Installation ................................ 4
6.5 Insulation .............................................................. 4
6.6 Installation Scheme ........................................... 5
6.7 Assembly Drawings, Dimensions ................ 6
7 Start-up ..................................................................8
7.1 Required static Pressure .................................. 8
7.2 Leak and Pressure Test ...................................... 8
7.3 Filling the System ............................................... 8
7.4 Start-up .................................................................. 8
7.5 Putting out of Operation ................................. 8
7.6 Flow Rate Adjustment ...................................... 9
7.7 Flow Adjusting Curves ................................... 10
7.8 Sealing ................................................................. 12
7.9 Adjustement of the Throttle Valves .......... 12
7.10 Function Test ..................................................... 12
8 Trouble Shooting ......................................... 13
9 Replacement of Valve,
Actuator, Trims .............................................. 14
9.1 Dismounting and
Mounting Actuator Valve ............................. 14
9.2 Replacement of Trim Valve VFQ 21 ........... 16
9.3 Dismounting,
Mounting Actuator AVP-F ............................ 17
9.4 Replacement of Trim Valve AVP-F .............. 17

Pilot controller AVP-F
(Flow Rate)
Adjusting throttle
Throttling element DE
Valve unit PCV-VFQ 21
Throttling valve
T
hrottling valve
only by DN150-250
2 VI.JA.G2.02 © Danfoss 11/2006 DH-SMT/SI
Instructions Pilot-controlled PCVQ DN 100 - DN 250 (PN 16, PN 25)
1 Safety Notes To avoid injury of persons
and damages to the device,
it is absolutely necessary to
carefully read and observe
these Instructions.
Necessary assembly, start-up, and maintenance
work may be performed only by qualified and
authorized personnel.
Please comply with the instructions of the
system manufacturer or system operator.
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 to 140 °C,
5 to 150 °C, 5 to 200 °C.
The technical data on the rating plates
determine the use.
3 Description
3.2 Mode of Operation
The control unit consists of the PCV-VFQ21
valve unit, installed in the main pipe and AVP-F
installed as pilot controllers in the bypass. In the
bypass line, a throttle element is installed in front
of the pilot controller.
The controller keeps the differential pressure
across the main valve flow restrictor on a
constant level and restricts the flow rate to the
adjusted setpoints.
The valve and the pilot valves are pressure-
balanced.
The setpoint for the flow rate limitation is
adjusted at the adjusting throttle of the valve
unit.
The valve unit in the main pipe is opening on
rising pressure. The pilot controller in the bypass
line is closing on rising pressure.
3.1 Construction
Flow Rate Limitation
If the flow rate reaches the adjusted setpoint, the
differential pressure increases at the adjusting
throttle. This differential pressure acts on the
actuator AVP-F via the impulse tubes and the
valve AVP-F closes. Consequently, the valve of
the valve unit is throttled, too, and the flow rate
is restricted.

DH-SMT/SI VI.JA.G2.02 © Danfoss 11/2006 3
Instructions Pilot-controlled PCVQ DN 100 - DN 250 (PN 16, PN 25)
4 Technical Data Technical data, see rating plates and the PCV
data sheet.
5 Scope of Delivery
DN 100, DN 125
Assembly kit valve unit PCV-VFQ 21 Pilot controller DN 25
AVP-F
Throttling element
Cu pipe Ø 6 × 1 × 1500 mm
Cu pipe Ø 10 × 1 × 3000 mm
DN 150, DN 250
Assembly kit valve unit PCV-VFQ 21 Pilot controller DN 40
AVP-F
Throttling element
Cu pipe Ø 6 × 1 × 1500 mm
Cu pipe Ø 10 × 1 × 3000 mm

pin only
weld
do NOT
weld
1
2
4 VI.JA.G2.02 © Danfoss 11/2006 DH-SMT/SI
Instructions Pilot-controlled PCVQ DN 100 - DN 250 (PN 16, PN 25)
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 Place
• Installation is only permitted in horizontal
pipelines with the actuators hanging in a
downward position.
• The controller may be installed in the
supply as well as in the return line.
6.3 When installing:
• 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
See installation scheme, section 6.6.
For CU pipes Ø 10 × 1, insert sockets 1 on both
sides.
Care for correct position of the cutting rings 2.
6.5 Insulation
The diaphragm actuators must not be insulated
when insulating system parts.

Bypass controller
PCVQ
Throttling
element
Throttling valve
Throttling valve
(only by DN 150 - 250)
Valve unit PCV - VFQ 21
Pilotregler AVP-F
lay impulse tube during mounting
Bypass controller
PCVQ
Throttling
element
Throttling valve
Throttling valve
(only by DN 150 - 250)
Valve unit PCV - VFQ 21
Pilot controller AVP-F
DH-SMT/SI VI.JA.G2.02 © Danfoss 11/2006 5
Instructions Pilot-controlled PCVQ DN 100 - DN 250 (PN 16, PN 25)
6.6 Installation Scheme
Installation in the Return Line
Installation in the Supply Line
6 Assembly

H1 H2
D2
Cu pipe
Ø 10 × 1
Lay when assembling.
CU pipe Ø 6 ×1
Lay when assembling.
244
160
ca. 1000
A
159
75
L1
DN 25: pipe Ø33.7 × 3.2
Material: ST 35.8
(not part of the delivery)
DN 25 SW 50
Pilot controller AVP-F
Throttling element
6 VI.JA.G2.02 © Danfoss 11/2006 DH-SMT/SI
Instructions Pilot-controlled PCVQ DN 100 - DN 250 (PN 16, PN 25)
6 Assembly 6.7 Assembly Drawings, Dimensions
DN 100 - DN 125

L1
D 2
H1 H2
Cu pipe
Ø 10 × 1
Lay when assembling.
CU pipe Ø 6 × 1
Lay when assembling.
ca. 1200
290
A
B
D1
200
DN 40: pipe Ø 48.3 × 3.2
Material: ST 35.8
(not part of the delivery)
DH-SMT/SI VI.JA.G2.02 © Danfoss 11/2006 7
Instructions Pilot-controlled PCVQ DN 100 - DN 250 (PN 16, PN 25)
6 Assembly (continuous) DN 150 - DN 250
Nominal
diameter DN 100 125 150 200 250
L1
mm
350 400 480 600 730
H1 530 530 619 647 697
H2 - 245 300 325
D2 263 380
D1 250 320 385 500
B 200 210 310 336 412
A ≥ 290 320 350 410

p1
p2
1
54
2
3
7 6
8
8 VI.JA.G2.02 © Danfoss 11/2006 DH-SMT/SI
Instructions Pilot-controlled PCVQ DN 100 - DN 250 (PN 16, PN 25)
7 Start-up 7.1 Required Static Pressure
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 4 is closed when no pressure is
applied and only opens with a defined flow in the
bypass.
The pilot controller 5 is 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 2 is 25 bar 1). For higher pressures, you
must:
• Remove the impulse tubes 3 at 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.
To avoid too high pressure
differences on the controller,
observe the following sequence
when starting-up !
This procedure guarantees that there is no
overturn of the diaphragm in the valve and the
actuators.
1. Open units 6 of the system.
2. Slowly open shut-off units in the supply
flow 7 and the return flow 8.
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.

1
2
Required
flow rate
Read rotations
for the adjusting throttle
3
DH-SMT/SI VI.JA.G2.02 © Danfoss 11/2006 9
Instructions Pilot-controlled PCVQ DN 100 - DN 250 (PN 16, PN 25)
7.6 Flow Rate Adjustment
The setting of the setpoint for the flow rate
limitation is made by means of flow adjusting
curves (see section 7.7) or a heat meter (see
page 33).
Adjustment by means of flow adjusting
curves
Adjustment is to be made at a shut-down
system.
Procedure
4. Turn the adjusting throttle by this number of
rotations to the left.
1. Unscrew cover 1.
2. Loosen the counter nut 2.
3. Choose diagram,
(see section 7.7, Flow Adjusting Curves)
Observe effecitve pressure Δpb: 0.2 or 0.5 bar
see rating plate on the actuator AVP-F
5. The adjusted flow rate can be verified by
means of a flow rate measuring device.
Perhaps you need to re-adjust the flow rate.
Care for an adequate differential pressure in
the system.
6. Tighten the counter nut without changing the
position of the adjusting throttle.
7. Re-screw the cap nut 1.
8. The cap nut can be sealed.
The flow rate adjustment is completed.
Now, adjust the differential pressure,
see section 7.8.
2. Screw.in the adjusting throttle 3 to its stop.
7 Start-up

DN 100 kvs 125 / DN 125 kvs 160 / DN 150 kvs 320
0
20
40
60
80
100
120
140
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14
∆pb=0,2
DN100 / 125
DN150
Rotations for the adjusting throttle
Flow rate (m3/h)
DN 100 kvs 125 / DN 125 kvs 160 / DN 150 kvs 320
0
20
40
60
80
100
120
140
160
180
200
220
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14
DN100 / 125
DN150
∆pb=0,5
Rotations for the adjusting throttle
Flow rate (m3/h)
DN 200 kvs 450 / DN 250 kvs 630
0
20
40
60
80
100
120
140
160
180
200
0 1 2 3 4 5 6 7 8 9 10
DN 200
DN 250
∆pb=0,2
necessary
rotations of the
adjusting throttle: 4
Example
Ventil DN 200
required flow rate
limitation: 100 m³/h
Rotations for the adjusting throttle
Flow rate(m3/h)
DN 200 kvs 450 / DN 250 kvs 630
0
20
40
60
80
100
120
140
160
180
200
220
240
260
0 1 2 3 4 5 6 7 8 9
DN 200
DN 250
∆pb=0,5
Rotations for the adjusting throttle
Flow rate(m3/h)
10 VI.JA.G2.02 © Danfoss 11/2006 DH-SMT/SI
Instructions Pilot-controlled PCVQ DN 100 - DN 250 (PN 16, PN 25)
7 Start-up
7.7 Flow Adjusting Curves