Exhaust Gas System; Connecting The Cooling System; Vent Tank And Test Pipe; Aligning Pump And Engine - Grundfos Fire NKF Series Installation And Operating Instructions Manual

5.1.6 Exhaust gas system

Warning
The exhaust gas system must be installed
correctly according to local regulations and must
have no leaks. Operation without exhaust gas
system is not permitted.
Exhaust gases are to be directed safely to the
open air through the exhaust system.
Exhaust fumes must not escape indoors.
Danger of suffocation!
Hot exhaust pipes must be protected to prevent
accidental touch. Danger of burns!
Install exhaust pipes as straight and with as few bends as
possible. Install the supplied silencer horizontally and at a
sufficient distance to the engine. The exhaust system is to be
arranged so that no condensation water can enter the engine.
The exhaust system must be fixed to the building. The flexible
connections must not be used to compensate for misaligned
pipework. The minimum diameter of the exhaust pipes must not
be smaller than the exhaust port on the engine.

5.1.7 Connecting the cooling system

The flow diverged through the bypass pipe is used for cooling the
engine. The bypass pipe is thus connected to the heat exchanger
via a cooling circuit. Fit a tube on the discharge side of the heat
exchanger. The other end of the tube must be a visible free
outlet, according to VdS regulations. The nominal tube diameter
must not be smaller than the outlet on the heat exchanger.
The cooling circuit consists of the pipe system, a shut-off
cock (A), a diaphragm valve (B) and a pressure gauge (C).
See fig. 20.
Additional
Zusätzliche
pipe
Leitung
A
B
Fig. 20 Cooling circuit
In addition to the suction pipe of the pump, an extra pipe must be
installed. This pipe prevents water from escaping out of the
storage tank via the pump and the heat exchanger, when the
filling level in the storage tank is above the open discharge of the
heat exchanger. The pressure on the suction side then ensures
the closure of the diaphragm valve (fig. 20, pos. B). The shut-off
cock (fig. 20, pos. A) is closed during normal operation. It should
only be opened if the diaphragm valve is faulty and remains in the
closed position. A diaphragm valve blocked in the closed position
is indicated by a lack of pressure on the pressure gauge (fig. 20,
pos. C).

5.1.8 Vent tank and test pipe

If the pump unit is supplied from a storage tank, a pump priming
tank must be installed on the suction side, in accordance with the
regional regulations, see VdS CEA guidelines for sprinkler
systems.
A test pipe diverging from the pressure pipe and leading to the
storage tank must be installed. Both the pressure pipe and the
test pipe must be fitted with isolating valves. If the pump unit is
fed directly from the public water supply, the test pipe must have
a free outlet, see VdS CEA guidelines for sprinkler systems.
16

5.1.9 Aligning pump and engine

A flexible coupling connects engine and pump. See fig. 21.
Fig. 21 Flexible coupling between pump and engine
The coupling is bolted axially on the engine fly-wheel. The pump
shaft is pushed on axially and bolted radially with four bolts.
See fig. 22.
A-A
C
Fig. 22 Connection and alignment of pump and engine
When a complete unit is delivered pre-assembled from the
factory, the coupling has been accurately aligned by means of
shims inserted under the pump and engine, if required.
During transport and installation, the pump-engine alignment may
have been affected. Therefore the alignment must always be
checked when the complete unit has been installed.
Check the final alignment when the pump has obtained its
operating temperature under normal operating conditions.
A careful alignment is important for a long
service life of the coupling. This is particularly
Caution important with increased engine speed.
Follow the installation instructions of the
coupling manufacturer.
Checking the alignment
Warning
Before removing the coupling guard, disconnect
the battery cable.
1. Disconnect the battery (negative pole).
2. Remove the coupling guard.
3. Measure the distance "Z" at the rubber element of all axially
bolted points. See fig. 22. The distance must be 50 mm. If the
alignment is correct, proceed with step 4; otherwise align
pump and engine. See next point.
4. Refit the coupling guard.
5. Reconnect the battery.
A
A