Figure 6 : Water Connection On Unit - Riello NXHP Series Installation, Operation And Maintenance Instructions

2 - INSTALLATION OF UNIT
■ If the external unit water pipes are in an area where the ambient
temperature is likely to fall below 0°C, they must be protected
against frost (frost protection solution or trace heating).
■ The use of different metals on hydraulic piping could generate
electrolytic pairs and consequently corrosion. Verify then, the
need to install sacrificial anodes.
The plate heat exchanger can foul up quickly at the initial unit
start-up, as it complements the filter function, and the unit
operation will be impaired (reduced water flow rate due to
increased pressure drop).
Do not introduce any significant static or dynamic pressure
into the heat exchange circuit (with regard to the design
operating pressures).
The products that may be added for thermal insulation of the
2.3.2 - General
For details on connection diameters, refer to §1.5.1 Physical data.
B
C
D
E
F
G
2.3.3 - Minimum water loop volume
The minimum water loop volume, in litres, is given by the following
formula:
Volume (l) = Model number x N
Where CAP is the nominal cooling capacity at nominal operating
conditions.
Application
Air conditioning
Heating or domestic hot water application
24
containers during the water piping connection procedure
must be chemically neutral in relation to the materials and
coatings to which they are applied. This is also the case for
the products originally supplied by the manufacturer.
The installation of an external filter (Y shape) at the unit inlet
side is highly recommanded. The mesh size must be
comprised between 16/10e mm and 20/10e mm.
The unit is using R290 refrigerant. In case of leak, the
refrigerant must not accumulate in a not ventilated area. The
condensate draining pipe must be connected to a solution
allowing the free evacuation of water during defrost. This
solution must not permit the accumulation of refrigerant in
the case of a leak inside the unit (syphon).

Figure 6 : Water connection on unit

This volume is required to obtain temperature stability and
precision. To achieve this volume, it may be necessary to add a
storage tank to the circuit. This tank should be equipped with
baffles to allow mixing of the fluid (water or brine). Please refer to
the examples below.
N
8
12
Legend:
B
Outside Air Temperature sensor
C
Customer electrical connection
D
Water inlet
E Water outlet
F
Water drain pipe
G
Condensate draining pipe"