Viessmann NC-Box Operating instructions

Installation and service instructions
for contractors
VIESMANN
NC-Box
Pre-assembled unit for implementing the natural cooling function in conjunction
with brine/water heat pumps up to 17 kW
For applicability, see the last page
NC-Box
5675 869 GB 2/2015 Please keep safe.

2
Please follow these safety instructions closely to
prevent accidents and material losses.
Safety instructions explained
Danger
This symbol warns against the risk of injury.
!Please note
This symbol warns against the risk of material
losses and environmental pollution.
Note
Details identified by the word "Note" contain additional
information.
Target group
These instructions are exclusively intended for author-
ised contractors.
■Work on the refrigerant circuit may only be carried
out by authorised refrigeration engineers.
■Work on electrical equipment must only be carried
out by a qualified electrician.
■The system must be commissioned by the system
installer or a qualified person authorised by the
installer.
Regulations to be observed
■National installation regulations
■Statutory regulations for the prevention of accidents
■Statutory regulations for the protection of the envi-
ronment
■Codes of Practice of the relevant trade associations
■All relevant safety regulations as defined by DIN, EN,
DVGW, VDE and locally applicable standards
aÖNORM, EN and ÖVE
cSEV, SUVA, SVTI, SWKI and SVGW
Working on the system
■Isolate the system from the power supply (e.g. by
removing the separate fuse or by means of a mains
isolator) and check that it is no longer 'live'.
Note
In addition to the control circuit there may be several
load circuits.
Danger
Contact with 'live' components can result in
severe injuries. Some components on PCBs
remain 'live' even after the power supply has
been switched off.
Wait at least 4 minutes before removing equip-
ment covers, to allow the voltage to dissipate.
■Safeguard the system against reconnection.
!Please note
Electronic assemblies can be damaged by elec-
trostatic discharge.
Prior to commencing work, touch earthed
objects such as heating or water pipes to dis-
charge static loads.
Repair work
!Please note
Repairing components that fulfil a safety func-
tion can compromise the safe operation of your
system.
Replace faulty components with genuine
Viessmann spare parts.
Auxiliary components, spare and wearing parts
!Please note
Spare and wearing parts that have not been tes-
ted together with the system can compromise its
function. Installing non-authorised components
and making non-approved modifications or con-
versions can compromise safety and may inva-
lidate our warranty.
For replacement, use only spare parts supplied
or approved by Viessmann.
Safety instructions
Safety instructions
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1. Information Symbols ................................................................................................. 4
Product information ................................................................................ 4
2. Preparing for installation Hydraulic connection with on-site pipework ........................................... 5
Hydraulic connection with hydraulic connection set .............................. 5
Siting and transport requirements .......................................................... 6
■Transport ............................................................................................ 6
■Installation room requirements ........................................................... 6
3. Installation sequence Fitting the NC-Box ................................................................................. 7
Opening the NC-Box .............................................................................. 8
Hydraulic connection ............................................................................. 8
■Preparation for retrofitting ................................................................... 8
■Required connections ......................................................................... 9
■Connection with hydraulic connection set .......................................... 10
■Installing the contact humidistat 24 V– ............................................... 10
Electrical connection .............................................................................. 12
■Required connections ......................................................................... 12
Power supply ......................................................................................... 14
Closing the NC-Box ............................................................................... 15
4. Commissioning and
adjustment
.................................................................................................................. 16
5. Parts lists Overview of assemblies ......................................................................... 18
■Parts not shown .................................................................................. 19
Hydraulics .............................................................................................. 20
Electrical equipment .............................................................................. 22
Connection set ....................................................................................... 24
6. Connection and wiring dia-
gram
.................................................................................................................. 26
7. Specification .................................................................................................................. 27
8. Declaration of conformity .................................................................................................................. 28
9. Keyword index .................................................................................................................. 29
Index
Index
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Symbol Meaning
Reference to other document containing
further information
1.
Step in a diagram:
The numbers correspond to the order in
which the steps are carried out.
Warning of material losses and environ-
mental pollution
Live electrical area
Pay particular attention.
■Component must audibly click into place.
or
■Acoustic signal
■Fit new component.
or
■In conjunction with a tool: Clean the sur-
face.
Dispose of component correctly.
Dispose of component at a suitable collec-
tion point. Do not dispose of component in
domestic waste.
Product information
Design and function
The NC-Box includes all hydraulic and electrical com-
ponents required for cooling a heating/cooling circuit or
a separate cooling circuit in conjunction with a brine/
water heat pump.
The temperature level of the primary circuit is directly
transferred to the cooling circuit for central cooling.
Hydraulic connections
The heating/cooling circuit or the separate cooling cir-
cuit and the primary circuit (brine) are hydraulically
connected directly to the NC-Box. The hydraulic con-
nection between the heat pump and the NC-Box can
be made on site or via the hydraulic connection set
(accessories).
Electrical connection
The NC-Box and the heat pump are connected electri-
cally. The cable for switching the NC-Box (NC signal)
is connected inside the NC-Box and routed outside at
the factory.
Product validity
The NC-Box can be used in conjunction with the fol-
lowing heat pumps:
■Vitocal 200-G
■Vitocal 222-G
■Vitocal 242-G
■Vitocal 300-G, types BW/BWC 301.A06 to A17
■Vitocal 300-G, types BW/BWC 301.B06 to B17
■Vitocal 333-G, types BWT 331.B06 to B10
■Vitocal 343-G
■Vitocal 350-G, type BW/BWC 351.A07
Information
Symbols
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Information

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For
■Vitocal 222-G/242-G and Vitocal 333-G/343-G
■Vitocal 200-G, Vitocal 300-G and Vitocal 350-G with-
out sufficient installation space above the heat
pump, e.g. when retrofitting
1. Fit the NC-Box near the heat pump on a wall capa-
ble of bearing the load.
2. Connect on-site connection lines so that they are
free of load and torque stress.
Hydraulic connection with hydraulic connection set
Vitocal 200-G, Vitocal 300-G and Vitocal 350-G with
sufficient installation space above the heat pump: See
page 7.
223
Fig.1
ANC-Box
BReturn, heating/cooling circuit or separate cooling
circuit
CFlow, heating/cooling circuit or separate cooling
circuit
DPrimary circuit flow (NC-Box brine entry)
ESecondary circuit return to heat pump
FSecondary circuit flow to the NC-Box
GHeat pump
HPrimary circuit flow (heat pump brine inlet)
KPrimary circuit BDF valve (brine)
LSecondary circuit BDF valve (heating water)
Preparing for installation
Hydraulic connection with on-site pipework
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Installation

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Transport
!Please note
Impacts, compression and tensile loads can
cause damage to the outside panels of the
appliance.
Never apply loads/weight to the top, front or
side panels of the appliance.
Installation room requirements
!Please note
Unfavourable ambient conditions can lead to
malfunctions and appliance damage.
■The installation room must be dry and free
from the risk of frost.
■Ensure ambient temperatures between 0 and
35 °C.
Danger
Dust, gases and vapours can be damaging to
health and trigger explosions.
Avoid dust, gases and vapours in the installation
room.
Preparing for installation
Siting and transport requirements
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Installation

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■Installation without hydraulic connection set:
Fit the NC-Box near the heat pump on a wall capable
of bearing the load.
■Installation with hydraulic connection set:
Fit the NC-Box above the heat pump with the clear-
ances shown in Fig. 2.
160
760
223
2.
2.
1.
Fig.2
Installation sequence
Fitting the NC-Box
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Installation

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2.
1.
1.
Fig.3
Note
Should there be insufficient space for working, front
casing part B can also be removed. First, remove
casing cover D and pull out the panel with cable
entries E.
ATerminal box
BFront casing part
CPower cable, heat pump connecting cables (NC
signal) and contact humidistat (connected at the
factory)
DCasing cover
EPanel with cable entries and strain relief fittings
Hydraulic connection
To prevent corrosion damage, provide all hydraulic
pipes with thermal insulation as vapour diffusion-proof
installation (on the brine and cold water sides) in
accordance with current engineering standards.
Preparation for retrofitting
1. Close ball valves and sliders. 2. Open the primary circuit (brine) and the secondary
circuit (heating water) at a suitable position and
drain the heat transfer medium.
Installation sequence
Opening the NC-Box
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Installation

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Required connections
Subject to the type of cooling circuit, the NC-Box can
be connected to the heat pump in two different ways.
Heating/cooling circuit, e.g. underfloor heating
Required hydraulic connection between the NC-Box
and heat pump:
■Primary circuit flow
■Secondary circuit flow and return
Separate cooling circuit, e.g. fan convector
Required hydraulic connection between the NC-Box
and heat pump:
■Primary circuit flow
For this, note the following:
■Seal the secondary circuit connector on the NC-Box.
■Connect the secondary circuit flow and return directly
on the heat pump.
■Equip a separate cooling circuit with a dedicated
expansion vessel and a safety valve (2.5 bar/
0.25 MPa).
Installation sequence
Hydraulic connection (cont.)
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Installation

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Connection with hydraulic connection set
A
B
C
1.
2.
Fig.4
Tightening torques for fitting the union nuts
Line Connection to
Heat
pump
NC-Box
Primary circuit flow A (heat
pump brine inlet)
70 Nm 70 Nm
Secondary circuit flow B70 Nm 50 Nm
Secondary circuit return C70 Nm 50 Nm
Installing the contact humidistat 24 V–
The contact humidistat monitors the formation of con-
densate on the flow of the heating/cooling circuit or of
the separate cooling circuit.
■Where the heating/cooling circuit extends over sev-
eral rooms with different relative humidity levels, it
may become necessary to provide several contact
humidistats.
■Where several contact humidistats are used, connect
all contact humidistats electrically in series.
■In the delivered condition, the contact humidistat
switches at a relative humidity of 80 %. This value
can be adjusted.
Contact humidistat installation instructions
Note
In the delivered condition, the contact humidistat is
located outside the NC-Box casing and is electrically
connected at the control panel. The associated con-
necting cable is routed through the cable entry in the
NC-Box.
Installation conditions: The flow and return of the heat-
ing/cooling circuit or the separate cooling circuit are
connected to the NC-Box.
Installation sequence
Hydraulic connection (cont.)
5675 869 GB
Installation