Nibe F370 Installer Manual page 18

Valve outlet size Minimum size of dis-
charge pipe
<G3>/4 22 mm
G1 28 mm
G1 28 mm
G1 28 mm
HARD WATER AREAS
There should not normally be any problem installing
F370 in hard water areas, as the operating temperature
is 50-60°C.
CLEANING THE CLIMATE SYSTEM
When the water heater and the climate system have
been filled with water, F370 must operate at maximum
normal temperature for at least one hour. Thereafter the
system must be drained of water and refilled.
Before installing the heat pump in an existing system,
it is important that the system is properly flushed
through.
Even if the heat pump is to be installed in a new system,
the heat pump and system should be flushed.
NOTE
Ensure that cleaning agent has been removed
from the entire system before adding inhibitor.
After flushing an inhibitor should be used for long-term
anti-corrosion protection.
NIBE Energy Systems Limited recommends water
treatments (supplied by e.g. Fernox and Sentinel) spe-
cifically designed for heat pumps.
Caution
Ensure that incoming water is clean. When
using a private well, it may be necessary to
supplement with an extra water filter.
18 Chapter 4 | Pipe and ventilation connections
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)
42 mm up to 27 m
35 mm up to 9 m
42 mm up to 18 m
54 mm up to 27 m
SYSTEM VOLUME
The volume of the pressure expan-
sion vessel (CM1) is 10 litres and
it is pre-pressurised as standard to
0.5 bar (5 mvp). As a result, the
maximum permitted height "H"
between the expansion vessel and
the highest installed radiator is 5
m, see figure.
If the pre-pressure is not high
enough, it can be increased by
adding air via the valve in the expan-
sion vessel. The expansion vessel's pre-pressure must
be stated in the inspection document. Any change in
the pre-pressure affects the ability of the expansion
vessel to handle the expansion of the water.
The maximum system volume, excluding F370, is 219
litres at the above pre-pressure.
Resistance created by
each elbow or bend
1.7 mm
1.4 mm
1.7 mm
2.3 mm
NIBE F370