Pipe And Ventilation Connections; General Pipe Connections - Nibe F470 Installer Manual

4 Pipe and ventilation
connections
General pipe
connections
Pipe installation must be carried out in accordance with
current norms and directives.
The system requires the radiator circuit to be designed
for a low temperature heating medium. At the lowest
dimensioned outdoor temperature (DOT) the highest
recommended temperatures are 55 °C on the supply
line and 45 °C on the return line.
NOTE
The pipe system needs to be flushed out be-
fore the heat pump is connected so that any
debris cannot damage component parts.
NOTE
This installation is subject to building regulation
approval, notify the local Authority of intention
to install.
NOTE
Use only manufacturer's recommended replace-
ment parts.
Waste water from the evaporator's collection tray and
from safety valves is led via an unpressurised overflow
pipe to the drain, so that hot water splashes cannot
cause damage.
Valve outlet size Minimum size of dis-
charge pipe
G1/2 15 mm
G1/2 15 mm
G1/2 15 mm
<G3>/4 22 mm
<G3>/4 22 mm
NIBE F470
The mouth of the overflow pipe must be visible and not
placed close to electrical components. In addition, the
mouth of the overflow pipe (tundish), drain valves and
motorised valves should also be positioned well away
from all electrical components. This is the only permitted
use of unpressurised overflow pipes. Overflow pipes
from tundish (WM1) connected to the expansion relief
valve (FL1) must also be connected to the drain in the
same way.
The connection for the T&P valve (XL29) must not be
used for any other purpose. Valves may not be posi-
tioned between the T&P valve (FL5) and the water
heater.
Overflow pipes from tundish must be routed with a fall
and be at least 300 mm long, before bends or angles in
the pipework (see image) and must also be frost-proof.
Safety device
(e.g. temperature
relief valve)
Max 600 mm
Min. 300 mm
Matal discharge pipe
from tundish, with
continous fall.
Minimum size of dis- Maximum resistance
charge pipe from tun- allowed, expressed as
dish a lenght of straight
pipe (i.e. no elbows or
bends)
22 mm up to 9 m
28 mm up to 18 m
35 mm up to 27 m
28 mm up to 9 m
35 mm up to 18 m
Chapter 4 | Pipe and ventilation connections
Metal discharge pipe
from temperature relief
valve to tundish
Tundish
Discharge
below fixed
grating
Resistance created by
each elbow or bend
0.8 mm
1.0 mm
1.4 mm
1.0 mm
1.4 mm
Possible
wall
Fixed
grating
Trapped
gulley
17