4
EN
2.3 Conditions of use
Check that the conditions of use match the DRVD delivered.
• Available pressure adjustment ranges: standard 1.5 to 6 bar,
optional 2 to 8 bar and 4 to 12 bar
• Maximum pressure: 16 bar, consult us for higher pressures
• Cold water, maximum temperature: 40°C
• Maximum flow rate:
The DRVD is a direct-acting pressure reducing valve:
it is controlled by the downstream pressure, which is exerted
under the piston against the force of the spring.
Pressure is adjusted by means of the adjuster screw (100): for
DN 50-100, (110): for DN125-200.
Loosen the locknut to release this screw. (220): for DN 50-100,
(240): for DN125-200.
• to increase pressure: turn clockwise,
• to reduce pressure: turn anti-clockwise,
The device’s pressure gauge connections are female 8x13
(1/4”).
Adjustment procedure:
• Isolate the DRVD: close the 2 isolation gates (4),
• Open the isolation gate of the air release valve (3); the filter (2)
must be clean and the pressure gauges installed,
• Fully decompress the spring of the DRVD by turning the
adjuster screw (110) anti-clockwise,
• The pressure needs to be adjusted if the flow rate is low:
open a downstream water inlet,
• Open the upstream isolation gate by 3-4 turns,
• Check the upstream pressure, which must be less than the
device’s permissible operating pressure,
• Adjust to the setpoint pressure and check on the downstream
pressure gauge,
• Close the water inlet,
•
Open the upstream and downstream isolation gates (4)
completely.
DN
50
65
80
100
Max flow rate(L/s)
4.1
7
10.6
16.5
DN
125
150
200
Max flow rate(L/s)
25.7
37.1
66
3. Commissioning and adjustment
4. Maintenance instructions
You are advised to have the device checked regularly by a
professional.
The device is designed for ease of maintenance. It can be
disassembled without removing it. Regularly clean the filter
fitted immediately upstream of the DRVD.
Shut off the water before carrying out any maintenance
operations. The device must be isolated and depressurised
It is imperative to:
• Every 3 months: check the upstream pressure and check
the setpoint pressure; adjust the latter if necessary.
• Every 12 months: replace the seal (160).
• Every 3 years: replace all the dynamic seals (available in a
single kit – see references below).
Any operations on the device other than maintenance
operations must be approved in advance by the After-
Sales Service of WATTS INDUSTRIES France.
1 - All internal parts of the DRVD can be accessed by remo-
ving the cover and the lower flange located under the device
(Item 200).
2 - Release the piston by unscrewing the piston screw (or the
piston nut depending on the diameter of the DRVD), which
can be accessed via the lower flange under the device. Use
lock-grip pliers (e.g. FACOM No. 500 or a clamp) to hold the
piston
3 - Unscrew the piston screw with a standard socket wrench
(e.g. FACOM No. 72) except for DRVDs with diameters of
125, 150 and 200, for which you will need an elbow-type
socket wrench (e.g. FACOM Nervus No. 92).
Summary of Contents for DN100
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