Danfoss Pilot-controlled PCVQ, PCV-VFQ 21 Instructions Manual

Instructions

Pilot-controlled PCVQ

DN 100 - DN 250
PN 16 / PN 25

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

73696700 DH -SMT/SI VI.JA.G2. 02 © Danfoss 11/2006 1

Pilot controller AVP-F
(Flow Rate)

Adjusting throttle

Throttling element DE

Valve unit PCV-VFQ 21

Throttling valv

e

T

hrottling valve

only by DN150-250

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

3 Description

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.

3.1 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.

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 pressure­balanced.
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.

2 VI.JA.G2. 02 © Danfoss 11/2006 DH-SMT/SI

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

DH-SMT/SI VI.JA.G2. 02 © Danfoss 11/2006 3

pin only

weld

do NOT

weld

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:

6.4 Impulse Tube Installation

See installation scheme, section 6.6.
For CU pipes Ø 10 × 1, insert sockets 1 on both
sides.

1

Care for correct position of the cutting rings 2.

2

6.5 Insulation

The diaphragm actuators must not be insulated
when insulating system parts.

• Loads on the valve body and the throttle
element by the pipes are not permitted.

4 VI.JA.G2. 02 © Danfoss 11/2006 DH-SMT/SI

Bypass controller
PCVQ

Throttling
elemen

t

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

Instructions Pilot-controlled PCVQ DN 100 - DN 250 (PN 16, PN 25)

6 Assembly

6.6 Installation Scheme

Installation in the Return Line

Installation in the Supply Line

DH-SMT/SI VI.JA.G2. 02 © Danfoss 11/2006 5

H1 H2

D2

Cu pipe
Ø 10 × 1
La

y when assembling.

CU pipe Ø 6 ×1
La

y 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 elemen

t

Instructions Pilot-controlled PCVQ DN 100 - DN 250 (PN 16, PN 25)

6 Assembly 6.7 Assembly Drawings, Dimensions

DN 100 - DN 125

6 VI.JA.G2. 02 © Danfoss 11/2006 DH-SMT/SI