18
4.6 Connecting the hot water coil
The hot water coil is an optional accessory for all DUPLEX R5 units. If it is included, it is supplied already installed in the unit in its
position. The maximum permitted temperature of the heating fluid is 55 °C (treated e.g. by mixing primary heating water or from
an automatically controlled source maintaining constant temperature) and operating pressure up to 0.25 MPa. Connection to
the heating system is recommended via a pair of shut-off valves, a filter for mechanical impurities, a visual thermometer and
pressure gauge and heating fittings.
The rigid line is connected to flexible hoses which run out through the unit’s casing and are terminated with a male thread. Before
connecting, remove the plastic covers used to prevent impurities from entering the system. The heating circuit must have a safety
valve and a closed presser vessel. The heat-carrying substance is untreated water, completely freed of air. The recommended
water hardness rate is between 7–12 °dH. If the water is harder, we recommend softening it. If necessary, an antifreeze can be
used as the heat-carrying substance (e.g. ethylene glycol). It is recommended that the supply and return line should be insulated.
Supply (and refill) water should meet in particular the following criteria:
• It must be clear and colourless.
• Its pH must not be lower than 7. If it contains dissolved neutral salts, its pH must be between 8.5 and 9.5. To make it alkaline
it is possible to use sodium hydroxide or sodium phosphate (Na
3
PO
4
).
• The content of carbon dioxide in ionic or covalent form must be kept at a minimum.
• The residual hardness of supply water should be lower than 7 mmol/l (at q < 23 kW/m
2
) and 5 mmol/l (at q > 23 kW/m
2
).
The water can be softened using sodium phosphate (Na
3
PO
4
) or a cation exchanger (in water harder than 7 mmol/l; systems
with large water volume; for electrical and radiation boilers).
• The amount of lime ions in the water must be up to 3.5 mmol/l (at q < 23 kW/m
2
) and up to 1.8 mmol/l (at q > 23 kW/m
2
).
• Total CO
2
up to 75 mg/l (at q < 23 kW/m
2
) and 10 mg/l (at q > 23 kW/m
2
)
The exact composition of the refill water is specified in CSN 07 7401 in attached Table 1.
The recommended connection diagrams are shown in a separate document: Recommended CH connections for R5 units
4.7 Connecting the integrated electric heater
The electric heater is an optional accessory for all types of DUPLEX R5 units. If it is included, it is supplied already installed in the
unit in its position. Its size must always match a particular unit and cannot be used interchangeably.
The heater must be connected to 400 V definitive power supply through a dedicated circuit breaking device including a trip coil
according to the recommended wiring diagram, see Appendix 8.2. The cable is connected to the terminals provided in the unit’s
electrical panel.
4.8 Connecting the cold water coil
The cold water coil is an optional accessory for all types of DUPLEX R5 units. If it is included, it is supplied already installed in the
unit in its position. The cold water coil can be filled with water or an antifreeze (e.g. ethylene glycol). The maximum permitted
operating pressure is 0.25 MPa.
4.9 Connecting the direct evaporator / condenser
The cold water coil is an optional accessory for all types of DUPLEX R5 units. If it is included, it is supplied already installed in the
unit in its position. It can be used as cooler or heater.
When connecting the direct cooler observe the instructions of the supplier of your condensation units and ductwork! The evaporator
is filled with inert gas (nitrogen) at the factory. The condensation unit is always supplied with a refrigerant charge.
!Before connecting ductwork to an outdoor condensation unit, remove the valve on the R_5 fluid circuit!
The recommended refrigerant type is R410A or R32 (depending on the condensation unit type – see the table in Chapter
2.43).
a) Most serious harmful effects of a leaked refrigerant on health
• Refrigerant vapours are heavier than air and may displace oxygen
• At atmospheric pressure refrigerant evaporates at -51.6 °C; its fast evaporation can therefore cause frostbites
• The substance can cause arrhythmia
b) Operator duties when a refrigerant leak or a fire is detected
• Unplug the unit from the power socket; when a refrigerant leak is detected, thoroughly air and immediately leave the affected
premises and do not come close to the unit
• Do not use an open flame
• Immediately report the incident to your servicing company and take further measures as per instructions
To Next Page
Loading...
