IMI PNEUMATEX Gunmetal Manual Del Usuario página 5

WZMOINxxxx
12.2018
PRV, PRV-F, PRV-SS
Installation | Operation
de
Installation and Adjustment
fr
The pressure reducer is factory set to a secondary pressure of 3
bar (in standard version) and is to be installed in the pipe without
en
any load. After the reducer a slow downsection of 5 x DN is
it
recommended. The flow direction must coincide with the arrow
es
on the housing. The valve can be mounted in any position. Pipes
must be thoroughly flushed prior to installation of the pressure
pl
reducer to prevent impurities picked up by the medium having
an impact on intended operation.
The pressure gauges are screwed into the sockets with
gasket strip and indicate the prevailing secondary pressure or
the prevailing primary and secondary pressure. The desired
secondary pressure is set by turning the adjusting spindle
at idle pressure (zero consumption). Turning the adjusting
spindle in clockwise direction increases the secondary pressure,
while turning it counter-clockwise reduces the secondary
pressure. During this adjustment always observe that, based
on pressure and friction losses, the end pressure adjusted at
zero consumption is reduced further when drawing water, in
dependence of the quantity drawn off. The set desired value can
be checked at the pressure gauge arranged on the secondary
pressure side.
Caution!
Before commissioning, ensure that both pressure
gauge connections on the housing are sealed with
pressure gauges or sealing plugs.
Maintenance
According to DIN EN 806-5, inspection and service is required
at least on an annual basis, in order to correct possible
malfunctions that can arise due to dirt, corrosion, calcification,
and natural wear. Depending on operating conditions this
interval may be shortened. During the service, the sieve must
be cleaned, the valve insert must be checked and if necessary
replaced. After long periods of non-use the function of the
valve must be tested.
Caution!
When carrying out any work on the pressure reducer
the corresponding system part must be relieved of
pressure and emptied, depending on the medium
used. At high temperatures, always wait for the
temperature to cool down to ambient temperature.
5
Replacing the Valve Insert
1. Remove plastic protective cap; loosen counter-nut
2. Tension spring by turning the setting spindle counter-clockwise
3. Unscrew spring housing or remove screws
4. Remove spring housing, spring plate, setting spindle, copper
ring and spring.
5. Using two screwdrivers pry out the valve insert (fig. a) and
replace with a new one. For DN65, DN80, and DN100 re-fit
two screws on opposite sides of the body, as these are
required to support the screwdrivers (fig. b)
6. Installation is the reverse of removal. For DN65, DN80,
and DN100, tighten screws equally without exceeding the
maximum torque. For DN65 and DN80, the maximum torque
is 20Nm, for DN100 the maximum torque is 30Nm.
Fig. a): Removal and installation of control unit PRV / PRV-SS
(DN15 - DN50)
Fig. b): Removal of control unit PRV-F (DN65 - DN100)
Cleaning the Dirt Trap
Release lock nut on adjusting spindle. Relieve spring pressure
by turning the spindle counter-clockwise. After unscrewing the
upper part and removing the spring, pull control unit out of the
housing. The strainer can now be pulled off and cleaned after
removing the bottom O-ring from the valve insert. After cleaning,
slide strainer over the valve insert and insert O-ring back in the
provided groove. Assemble complete valve insert.
Possible Faults, Troubleshooting
►Pressure gauge indicates pressure increase
In water heating systems in compliance with DIN 1988 and
DIN 4753 the non-return valve installed between pressure
reducer and water heater may be leaking, which, during the
heating process of the boiler, leads to the expanding water of
the boiler
causing a rise in secondary pressure at the pressure gauge
although the pressure reducer is operating correctly.
Remedial action: Replace non-return valve.
►Damage to the seat gasket or membranes
If the back pressure of the pressure reducer increases or if
water escapes at the top of the valve, this may be caused by
damage to the seat gasket and/or membranes.
Remedial action: Restore correct operation of the valve by
replacing the valve insert. If water discharges at the spring
bonnet, this may also simply be due to it not being screwed
tight.
►Scale (furring)
Pressure reducers are always to be installed in the cold water
supply of the system. The distance to the non-return valve
must be such that no hot water can be applied to the pressure
reducer, even in the event of the fitting leaking. If you do not
observe this rule during the installation there is a risk of the
pressure reducer liming up.
Remedial action: Correct the installation arrangement. If this is
not possible you must replace the complete valve insert from
time to time.