Grundfos iGRID P-Zone, Installation And Operating Instructions Manual, Page: 11 / 80

English (GB)
11
3.7.1 Filling of district heating water
Before starting, check that all valves are in the correct position as
follows:
• all valves in the main lines must be open.
• all drain cocks and vents must be closed.
Before starting the system, ensure the following:
• that the pump or pumps and the pipe system are filled with
water and vented
• that valves before pressure sensors are open and all closed
valves without connection to units are closed with a plug
• that all sensors are checked for correct measuring range
• that all wiring and cable connections are checked for correct
installation with reliefs and seals according to the heavy
current regulations
• that the direction of rotation of the pump or pumps is checked
• that the drainage pump in the drain pit has been tested for
proper operation.
Check the following for tightness after startup:
• Pipe connections, flanges and gaskets.
In case of a leakage, flanges are retightened and thread
assemblies are repackaged.
3.7.2 Starting P-Zone
• Ensure that the main valves are open.
• Connect mains supply voltage to the main
pump or pumps and the drainage pump.
• Adjust the setpoint to the desired operating pressure via the
operating panel of the pump or Grundfos GO Remote. See the
installation and operating instructions of the pump.
• Check the operating panel for any alarms and warnings. See
the installation and operating instructions of the pump.
3.7.3 Starting T-Zone
• Ensure that the main valves are open.
• Connect mains supply voltage to the main
pump or pumps and the drainage pump.
• Adjust the setpoint to the desired operating temperature via
the operating panel of the pump or Grundfos GO Remote. See
the installation and operating instructions of the pump.
• Check the operating panel for any alarms and warnings. See
the installation and operating instructions of the pump.
3.8 Complete work in the pit
4. Product introduction
4.1 P-Zone product description
Grundfos iGRID P-Zone is a prefabricated pumping station for
incorporation in a new or existing district heating network where
pressure boosting of the circulated district heating water is
desired.
The pit is constructed from PE (polyethylene) and is delivered as
standard with the following pre-assembled components:
• inlet and outlet pipes
• Isolating valves
• non-return valves
• pump or pumps including control unit
• pressure sensor
• connection points for sensors.
Inlet and outlet pipes for district heating connections are made of
steel lined with PU foam insulation and an outer sheath of PE
material welded to the pit wall at the pipe passage.
The pipe connections to the pump or pumps inside the pumping
station are assembled with flanges, bolts and gaskets inside the
pit.
The exterior pipe connections are welded to the buried districting
heating pipes in the district heating network.
The pump has one or more pumps of the CRE or TPE type built-in
for pressure boosting.
The pit provides the possibilty of incorporating a flow sensor
including a number of pressure and temperature sensors as
needed.
The pit is fitted with non-return and drain cocks to empty the
pipes of district heating water in the pit during service and
maintenance.
Ensure that the system is filled with water and vented
before startup.
CAUTION
Hot surface
Death or serious personal injury
- Use personal protective equipment when working
in the pit.
The pumps start automatically 5 seconds after the
supply voltage is connected.
The pumps start automatically 5 seconds after the
supply voltage is connected.
– Ensure that the cover is properly closed. Check
and remove foreign bodies, if any.
– The cover and locking device must be operated
by the same person.
– The cover and locking device must only be used
when no persons are in the pit.
WARNING
Falling hazard
Death or serious personal injury
- Ensure that the cover has been properly closed
and locked when work in the pit has been
completed.