Watts DRV Series Instruction Manual

WattsIndustries.com
DRV, DRVM, DRVN,
DRVMN Series
Pressure reducing valves
Technical Data Sheet

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Watts Water Technologies, Inc.
Spare unions complete with nut and seals for DRV Series pressure reducing valves.
R/DRV
Type Part No. DN Weight (Kg)
R/DRV 0599001 1/2” MM 0,1
R/DRV 0599002 3/4” MM 0,2
R/DRV 0599003 1” MM 0,3
R/DRV 0599004 1.1/4” MM 0,5
R/DRV 0599005 1.1/2” MM 0,7
R/DRV 0599006 2” MM 1,1
Diaphragm pressure reducing valve with compensated seat and complete with unions.
CW617N brass body and cap. Stainless steel strainer. Polymer valve seat.
Max. inlet pressure: 25 bar. Adjustable downstream pressure: 1.5÷6 bar. Can be used for
water, air and neutral gases up to 60°C, in accordance to DVGW up to 30°C. Pressure
drops less than 1.3 bar at characteristic flow rate.
Noise < 20 dB - Class 1 according with DIN 52218. LAG (DN 15÷32)
Compliant with DVGW, SVGW. Metallic materials in accordance with UBA LIST.
DRV
Type Part No. DN Weight (Kg)
DRV 0501115 1/2” MM 0,9
DRV 0501120 3/4” MM 1,2
DRV 0501125 1” MM 1,7
DRV 0501132 1.1/4” MM 3,1
DRV 0501140 1.1/2” MM 5,1
DRV 0501150 2” MM 6,3
The DRV, DRVM, DRVN, DRVMN Series pressure reducing valves are devices capable of reducing the pressure of the
fluid downstream to a desired level and keeping it constant even in the presence of major variations in the flow rate and/or
pressure upstream, by modifying its pressure drops.
Like DRV, but with M1-ABS50 Series pressure gauge (Scale 0-6 bar).
DRVM
Type Part No. DN Weight (Kg)
DRVM 0501315 1/2” MM 0,9
DRVM 0501320 3/4” MM 1,3
DRVM 0501325 1” MM 1,8
DRVM 0501332 1.1/4” MM 3,5
DRVM 0501340 1.1/2” MM 5,1
DRVM 0501350 2” MM 6,3
Spare regulator unit complete with cartridge, diaphragm and O-Ring for DRV Series
pressure reducing valves.
GRDRV
Tipo Part No. DN Weight (Kg)
GRDRV 0599025 1/2” MM 0,1
GRDRV 0599026 3/4” MM 0,1
GRDRV 0599027 1” MM 0,2
GRDRV 0599028 1.1/4” MM 0,3
GRDRV 0599029 1.1/2” MM 0,9
GRDRV 0599030 2” MM 1,0
Description

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Watts Water Technologies, Inc.
Patented diaphragm pressure reducing valve with compensated seat, outlet pressure
adjustable with a knob and external graduated scale for easy reading of set pressure.
Complete with unions. Body of CW617N sand-blasted stamped brass.
Stainless steel filter cartridge. Pressure gauge connection on both sides: G1/4”.
Maximum inlet pressure: 25 bar. Adjustable downstream pressure: 1,5 and 6 bar. Max.
operating temperature: 30°C. Can be used for water, air and neutral gases.
Noise < 20 dB - Class 1 according with DIN 52218
Compliant with DVGW. Metallic materials in accordance with UBA LIST.
DRVN
Type Part no. DN Weight (Kg)
DRVN 0502515 1/2” MM 0,6
DRVN 0502520 3/4” MM 0,9
DRVN 0502525 1” MM 1,3
DRVN 0502532 1.1/4” MM 2,1
DRVN 0502540 1.1/2” MM 3,4
DRVN 0502550 2” MM 4,2
Like DRVN but with M3A-ABS50 Series pressure gauge (Scale 0÷6 bar).
DRVMN
Type Part no. DN Weight (Kg)
DRVMN 0502615 1/2” MM 0,7
DRVMN 0502620 3/4” MM 1,0
DRVMN 0502625 1” MM 1,4
DRVMN 0502632 1.1/4” MM 2,2
DRVMN 0502640 1.1/2” MM 3,5
DRVMN 0502650 2” MM 4,3
Technical features: DRV and DRVN
Maximum upstream pressure 25 bar
Downstream pressure (outlet) 1,5÷6 bar
Connections M/M tailpiece
Downstream pressure adjustment (screw 4) Clockwise rotation: increases pressure
Anticlockwise rotation: decreases pressure
Downstream pressure gauge (DRV-M only) Pressure gauge Ø50 scale 0÷6 bar
Maximum operating temperature DRVN 30°C
Maximum operating temperature DRV 60°C (30°C DVGW)
Design features: DRV and DRVN
Body Sand blasted CW617N
Cap Sand-blasted/(DRV) CW617N,
Reinforced polymer (DRVN)
Plug Brass CW617N
Inlet/outlet connections Brass CW617N
Diaphragm NBR reinforced with nylon fabric compliant with KTW and
W270 - KTW
Seal and O-Ring NBR - KTW - W270
Spring Galvanized steel
Adjusting screw and lock nut Brass CW617N
Filters Stainless steel

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Watts Water Technologies, Inc.
Pressure reducing valves are used:
• In sanitary systems
- to keep the pressure of the water constant in the distribution network downstream of the valve
- to avoid excessive withdrawals of water by controlling the pressure at the tap
- to keep the water pressure constantly below the maximum value allowed
• In compressed air systems
- to keep the pressure constant in the network, irrespective of the oscillations in the pressure supplied by the
compressors
• Downstream of storage tanks or cylinders
- to reduce and stabilize the pressure in the network, which is normally lower
The pressure reducing valves are used not only for water but also for air and non-aggressive gases.
The DRV, DRVM, DRVN, DRVMN Series pressure reducing valves are compensated seat type. This means that as the
inlet pressure acts on the two openings A and B (see Fig.1) having the same cross section, it is compensated and does not
therefore result in any force on the pin-plug system when the opening angle of the valve is varied. The outlet pressure acts
on the diaphragm and thus also on the pin–plug system, which is thus subjected to two contrasting forces: the force exerted
by the outlet pressure, which tends to close the plug and the force exerted by the spring, which tends to open it. As a result,
the compensated seat valve has an outlet pressure virtually insensitive to variations in pressure upstream.
DRV DRVN
Features:
1 Body
2 Cap
3 Adjustment knob
4 Setting screw
5 Spring
6 Diaphragm
7 Inlet connection
8 Pin
9 Plug
10 Filters
11 Outlet connection
Features:
1 Body
2 Cap
3 Lock nut
4 Setting screw
5 Spring
6 Diaphragm
7 Inlet connection
8 Pin
9 Plug
10 Guide bushing
11 Filters
12 Outlet connection
1
10
11
2
3
4
5
6
8
9
7
Fig.1
Fig.2
3
2
1
12
11
10 9
8
6
5
4
7
AB
Application
Operation

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Watts Water Technologies, Inc.
The difference between the downstream pressure P2 measured with no flow and the same pressure measured at
the generic flow rate Q represents the pressure drop DP of the pressure reducing valve. It depends on the flow
rate, as indicated by the pressure drop diagrams. If you want the downstream pressure never to exceed a given
value P2, you must regulate this to value P2 with no flow. At flow Q, the downstream pressure will be less than
value P2 by an amount equivalent to the pressure drops DP. If the pressure reducing valve is installed to
guarantee that the downstream pressure reaches a given value P2 at a given flow rate Q, this pressure must be
regulated to value P2 + DP with no flow. At flow rate Q, the downstream pressure will be equivalent to P2.
The criterion for choosing the pressure reducing valve consists in determining the diameter in such a way that the speed of
the fluid does not reach excessively high values, at the rated flow rate, causing excessive pressure drop and outflow noise
transmitted to the distribution network. The flow rate-speed diagrams help you to choose the diameter of the pressure
reducing valve in the case of liquids (see water) or gases at pressures of 8-10 bar (see air).
Example 1 (cavitation)
Pressure reducing valve with:
Inlet pressure P1=14 bar
Outlet pressure P2=3 bar
From the cavitation diagram it can be seen that the pressure reducing valve is constantly working in the red zone.
To avoid rapid deterioration, two pressure reducing valves could be used, one connected upstream to the other.
Upstream pressure reducing valve: pressure front from 14 to 6 bar (green zone).
Downstream pressure reducing valve: pressure front from 6 to 3 bar (green zone).
Example 2 (flow rate)
DRV/N pressure reducing valve with:
Inlet pressure (minimum) P1=8 bar
Outlet pressure P2=4 bar
Maximum flow rate Q = 50 l/min
From the flow rate-speed diagram, it can be deduced that a 20 or 25 diameter should be used.
From the pressure drop diagram, the following two cases emerge:
DRV20/N Q = 50 l/min Dp=1.1 bar
DRV25/N Q = 50 l/min Dp=0.68 bar
Setting
Sizing
Exemples of sizing

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Watts Water Technologies, Inc.
The cavitation diagram shows three operating zones of the pressure reducing valve plotted against the upstream and downstream
pressures, namely:
C zone: normal duty, no cavitation
B zone: medium duty, risk of cavitation
A zone: heavy duty, the pressure reducing valve shows cavitation.
Continuous operation in the red cavitation zone could cause rapid damage of the internal parts. If the pressure reducing valve is to
operate in the red zone, contact the Technical Department of Watts Industries Italia.
20
18
16
14
12
10
8
6
4
2
0
01 2 3
Downstream pressure (bar)
4 5 6 7
A
B
C
Inlet pressure (bar)
A Cavitation Zone B Transition Zone C Work Zone
Flow rate
Speed (m/s)
DN15
30
20
10
8
1
0,6
0,4
0,2
0,1
0,1 0,2 0,4 0,6 0,8 246102060 200 1000
1840 100 400 600
10 50 100 1000 100005 500 5000
6
4
2
0,8
Acqua
Aria
m3/h
l/min
DN20
DN25
DN32
DN40
DN50
Cavitation
Cavitation diagram
Charts
DRV-DRVN

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Watts Water Technologies, Inc.
Flow rate
0,08
0,1
0,2
0,3
2
0,6
0,4
Pressure drop
bar
l/m
0,8
1
12 43568 20 3010 40 60 80 100 200 400
DRV50
DRV40
DRV32
DRV25
DRV20
DRV15
0,08
0,1
0,2
0,3
2
0,6
0,4
Pressure drop
Flow rate
bar
l/m
0,8
1
12 43568 20 3010 40 60 80 100 200 400
DRVN50
DRVN40
DRVN32
DRVN25
DRVN20
DRVN15
DRV
DRVN

Watts Industries Italia S.r.l.
Via Brenno, 21 • 20853 Biassono (MB) • Italy
Tel. [phone] • Fax [phone]
[e-mail] • www.wattsindustries.com
© 2017 Watts
The descriptions and photographs contained in this product specification sheet are supplied by way of information only and are not binding.
Watts Industries reserves the right to carry out any technical and design improvements to its products without prior notice. Warranty: All sales and contracts for sale are expressly
conditioned on the buyer’s assent to Watts terms and conditions found on its website at www.wattsindustries.com. Watts hereby objects to any term, different from or additional to
Watts terms, contained in any buyer communication in any form, unless agreed to in a writing signed by an officer of Watts.
DRV-DRVM-DRVN-DRVMN-TS-IT-W-UK-09-17-Rev2
DRV-DRVM
L1
D
L
D
H1
H
DN L L1 H H1
1/2” 97 152 136 48
3/4” 110 171 155 58
1” 114 175 176 66
1.1/4” 140 211 227 75
1.1/2” 159 245 253 82
2” 175 261 263 88
DRVN-DRVMN
L1
L
D
H
D
H1
DN L L1 H H1
1/2” 84 135 113 16,5
3/4” 94 151 133 20,5
1” 104 161 140 26
1.1/4” 109 175 192 29,5
1.1/2” 134 214 200 36
2” 144 224 205 42
Overall dimensions (mm)
DRV Series
Diaphragm pressure regulator with compensated seat complete with tailpiece WATTS brand DRV Series, with threaded
male thread DN 1/2 “-2”. Brass body CW617N. NBR membrane with nylon insert. Stainless steel internal filter. Noise: <20db
Class 1 in Germany. PN 25 bar. Adjustable downstream pressure: 1.5-6 bar with calibration screw. Maximum operating
temperature: 60°C (30°C DVGW). Compliant with DVGW, SVGW.
DRVM Series
Diaphragm pressure regulator with compensated seat complete with tailpiece WATTS brand DRV Series, with threaded male
thread DN 1/2 “-2”. Model with pressure gauge M1-ABS50 series scale 0-6 bar.Brass body CW617N. NBR membrane with
nylon insert. Stainless steel internal filter. Noise: <20db - Class 1 in Germany. PN 25 bar. Adjustable downstream pressure:
1.5-6 bar with calibration screw. Maximum operating temperature: 60°C (30°C DVGW). Compliant with DVGW, SVGW.
DRVN Series
Diaphragm pressure regulator with compensated seat complete with tailpiece WATTS brand DRVN Series, with threaded
male thread DN 1/2 “-2”. Brass body CW617N. NBR membrane with nylon insert. Stainless steel internal filter. Noise: <20db
Class 1 in Germany. DN 1/4 “pressure gauge on both sides. PN 25 bar. Adjustable downstream pressure: 1.5-6 bar with
manual knob and external graduated scale. Maximum operating temperature: 30°C. Compliant with DVGW.
DRVNM Series
Diaphragm pressure regulator with compensated seat complete with tailpiece WATTS brand DRVN Series, with threaded
male thread DN 1/2 “-2”. Brass body CW617N. NBR membrane with nylon insert. Stainless steel internal filter. Noise: <20db
Class 1 in Germany. Model with pressure gauge Series M1-ABS50 scale 0-6 bar. PN 25 bar. Adjustable downstream
pressure: 1.5-6 bar with manual knob and external graduated scale. Maximum operating temperature: 30°C.
Compliant with DVGW.
Specification text