Danfoss VVX-I User manual

Operating Guide
Termix VVX-I with complete insulation
1.0 Table of Contents
1.0 Table of Contents ............................................. 1
.0 Functional description......................................
3.0 Safety notes..................................................... 3
3.1 Safety Notes – general . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
4.0 Mounting ........................................................ 4
4.1 Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
4.2 Start-up. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4.3 Electrical connections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
5.0 Design............................................................. 10
5.1 Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
5.2 Sc ematic diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
6.0 Controls .......................................................... 1
6.1 Heating circuit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
6.2 DHW temperature control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
6.3 Ot er. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
6.4 Extras . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
6.5 Maintenance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
7.0 Troubleshooting ..............................................
7.1 Troubles ooting in general . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
7.2 Troubles ooting DHW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
7.3 Troubles ooting HE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
7.4 Disposal ............................................................. 26
8.0 Declaration...................................................... 7
8.1 Declaration of conformity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
© Danfoss | 2023.10 AQ082486478026en-010501/ LUK4044301 | 1

.0 Functional description
Indirect substation for flats and single family houses.
Application
T e Termix VVX-I is a complete solution for ot water and
space eating wit optimal safety, efficient energy transfer,
service-friendly construction and a compact design. T e substation
is used if a eat exc anger is required or on a conversion to district
eating w ere t e existing equipment is unsuitable for direct
connection.
District heating (DH)
T e substation is prefabricated wit a differential pressure
controller, fitting piece and sensor pockets for insertion of an
energy meter as well as strainers.
Heating (HE)
T e eating side consists of a plate eat exc anger, safety valve,
manometer, drain valve, air valve, expansion vessel and circulation
pump. T e temperature of t e eating can be controlled
t ermostatically or by an electronic controller wit an outdoor
temperature sensor. Depending on t e application, different eat
exc angers dimensioned for central or floor eating will be used.
Domestic hot water (DHW)
T e domestic ot water is prepared in t e eat exc anger and t e
temperature is regulated wit a flow-compensated temperature
controller wit integrated differential pressure controller. T e
DH water is cooled very efficiently by t e eat exc anger,
t ereby creating an excellent operating economy. T e IHPT
valve ensures a stable ot water temperature by varying loads,
supply temperatures and by ig and varying differential pressure
wit out t e need for readjusting t e valve. T is protects t e
eat exc anger against over eating and lime scale formation.
Furt ermore t e IHPT valve as an integrated idle temperature
controller, w ic keeps t e ouse supply line warm. T is s ortens
t e waiting periods during summer w en t e eating system is in
reduced operation, w ic is ideal w ere ig comfort is requested.
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3.0 Safety notes
3.1 Safety Notes – general
The following instructions refer to the standard design of
substation. Special versions of substations are available on
request.
T is operating manual s ould be read carefully before installation
and start-up of t e substation. T e manufacturer accepts no
liability for damage or faults t at result from non-compliance wit
t e operating manual. Please read and follow all t e instructions
carefully to prevent accidents, injury and damage to property.
Assembly, start-up and maintenance work must be performed by
qualified and aut orized personnel only.
Please comply wit t e instructions issued by t e system
manufacturer or system operator.
Corrosion protection
All pipes and components are made of stainless steel and brass.
T e maximum c loride compounds of t e flow medium s ould not
be ig er t an 150 mg/l.
T e risk of equipment corrosion increases considerably if t e
recommended level of permissible c loride compounds is
exceeded.
Energy source
T e substation is designed for district eating as t e primary
source of energy. However, also ot er energy sources can be used
w ere t e operating conditions allow it and always are comparable
to district eating.
Application
T e substation is designed to be connected to t e ouse
installation in a frost-free room, w ere t e temperature does not
exceed 50 °C and t e umidity does not exceed 60%. Do not cover
or wall up t e substation or in any ot er way block t e entrance
to t e station.
Choice of material
C oice of materials always in compliance wit local legislation.
Safety valve(s)
We recommend mounting of safety valve(s), owever, always in
compliance wit local regulations.
Connection
T e substation must be equipped wit features t at ensure t at
t e substation can be separated from all energy sources (also
power supply).
Emergency
In case of danger or accidents - fire, leaks or ot er dangerous
circumstances - interrupt all energy sources to t e station if
possible, and seek expert elp.
In case of discoloured or bad-smelling domestic ot water, close all
s ut-off valves on t e substation, inform t e operating personnel
and call for expert elp immediately.
REACH
All Danfoss A/S products fulfill t e requirements in REACH.
One of t e obligations in REACH is to inform customers about
presence of Candidate list substances if any, we ereby inform
you about one substance on t e candidate list: T e product
contains brass parts w ic contains lead (CAS no: 7439-92-1) in a
concentration above 0.1% w/w.
Storage
Any storage of t e substation w ic may be necessary prior to
installation s ould be in conditions w ic are dry and eated.
Authorized personnel only
Assembly, start-up and maintenance work must be performed by
qualified and aut orized personnel only.
Please observe instructions carefully
To avoid injury to persons and damage to t e device, it is absolutely
necessary to read and observe t ese instructions carefully.
Warning of high pressure and temperature
Be aware of t e installation’s permissible system pressure and
temperature.
T e maximum temperature of t e flow medium in t e substation is
120 °C.
T e maximum operating pressure of t e substation is 10 bar. PN 16
versions are available on enquiry.
T e risk of persons being injured and equipment damaged increases
considerably if t e recommended permissible operating parameters
are exceeded.
T e substation installation must be equipped wit safety valves,
owever, always in accordance wit local regulations.
Warning of hot surface
T e substation as got ot surfaces, w ic can cause skin burns.
Please be extremely cautious in close proximity to t e substation.
Power failure can result in t e motor valves being stuck in open
position. T e surfaces of t e substation can get ot, w ic can cause
skin burns. T e ball valves on district eating supply and return s ould
be closed.
Warning of transport damage
Before substation installation, please make sure t at t e substation
as not been damaged during transport.
IMPORTANT - Tightening of connections
Due to vibrations during transport all flange connections, screw joints
and electrical clamp and screw connections must be c ecked and
tig tened before water is added to t e system. After water as been
added to t e system and t e system as been put into operation,
re-tig ten ALLALL
ALL connections.
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4.0 Mounting
4.1 Mounting
Installation must be in compliance wit local standards and
regulations.
District eating (DH) - In t e following sections, DH refers to t e
eat source w ic supplies t e substations. A variety of energy
sources, suc as oil, gas or solar power, could be used as t e
primary supply to Danfoss substations. For t e sake of simplicity,
DH can be taken to mean t e primary supply.
Connections:
1. District eating (DH) supply
2. District eating (DH) return
3. Heating (HE) supply
4. Heating (HE) return
5. Domestic ot water (DHW)
6. Domestic cold water (DCW)
Connection sizes:
DH + HE: G ¾” (int. t read)
DCW + DHW: G ¾” (int. t read)
Dimensions (mm):
Wit insulation: H 800 x W 530 x D 375
Wit cover: H 800 x W 540 x D 430
Weight (approx.): 35 kg
Authorized personnel only
Assembly, start-up and maintenance work must be performed by
qualified and aut orized personnel only.
The pipe placement can deviate from the shown drawing. Please note
the markings on the station.
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4.1.1 Installation
Mounting:
Adequate space
Please allow adequate space around t e substation for mounting
and maintenance purposes.
Orientation
T e station must be mounted so t at components, key oles
and labels are placed correctly. If you wis to mount t e station
differently please contact your supplier.
Drillings
W ere substations are to be wall-mounted, drillings are provided
in t e back mounting plate. Floor mounted units ave support.
Labelling
Eac connection on t e substation is labelled.
Before installation:
Clean and rinse
Prior to installation, all substation pipes and connections s ould be
cleaned and rinsed.
Tightening
Due to vibration during transport, all substation connections must
be c ecked and tig tened before installation.
Unused connections
Unused connections and s ut-off valves must be sealed wit a
plug. S ould t e plugs require removal, t is must only be done by
an aut orized service tec nician.
Installation:
Strainer
If a strainer is supplied wit t e station it must be fitted according
to sc ematic diagram. Please note t at t e strainer may be
supplied loose.
Connections
Internal installation and district eating pipes connections must be
made using t readed, flanged or welded connections.
Keyhole for mounting.
4.1. Dismantle the insulation front
Pull t e insulation front using t e andle in t e top of t e cover
w ilst keeping t e ECL controller in its place.
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Keep t e ECL controller in its position w ile removing t e insulation
front completely by pulling at t e lower end of t e insulation front.
4.1.3 Mounting the display of the energy meter
Mark t e position of t e fixation points of t e bracket for t e energy
display and screw t e two plugs supplied into t e insulation front.
Mount t e bracket for t e display of t e energy meter.
Mount t e display/calculator of t e energy meter onto t e bracket.
Pull t e wires from t e sensors inside t e unit t roug t e
duct/cut-out in t e insulation plate.
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4. Start-up
Start-up, Indirect heating
Filling:
1: First fill
W en carrying out first fill, t e eat exc anger must be slowly filled
wit water until it reac es working pressure.
: Pressure gauge
T e HE pressure gauge indicates t e pressure of t e HE system. T is
instruction must be followed strictly, to avoid dangerous situations.
3: Supply hose
A ball valve wit plug is installed in t e HE return line. To fill t e
system, t e ball valve must first be closed, t e plug removed and
a supply ose connected. On re-opening t e ball valve, system
fill can commence.
4: Pre-pressure
W en filling t e system wit water, t e pressure gauge s ould be
observed closely. T e expansion vessel is supplied pre-pressurised
to 0.5 bar. T e pre-pressure required at eac substation will
depend on system ead (t e distance between t e lowest and
ig est point in t e system), for example:
5: Filling stop
Filling must stop w en t e pressure gauge s ows a pressure
approximately 1-2 bar ig er t an t e pre-pressure setting. T e
ball valve is t en closed, t e ose removed and t e plug put back
in.
Start-up:
1: Pump speed
Set t e pump to ig est speed before start-up.
: Start pump
Start t e pump and eat t roug t e system.
3: Open shut-off valves
T e s ut-off valves s ould t en be opened and t e unit observed
as it enters service. Visual c ecking s ould confirm temperatures,
pressures, acceptable t ermal expansion and absence of leakage.
If t e eat exc anger operates in accordance wit design, it can be
put to regular use.
4: Vent system
Switc off t e pump and vent t e installation after t e radiators
ave been warmed up.
5: Adjust pump speed
Set t e pump to t e lowest speed consistent wit comfort and
electricity consumption.
Normally t e c ange-over switc is set in t e mid position (default).
However for systems wit under floor eating or single pipe loop
systems, it may be necessary to turn t e c ange-over switc
upwards.
Hig er pump speeds are only used if t e eating requirement
increases.
Re-tighten connections
After water as been added to t e system and t e system as been
put into operation, re-tig ten ALLALL
ALL connections.
Pump
T e pump must be switc ed off during system fill.
Heig t (m) Pressure (bar)
0 – 5 0,5
5 – 10 1,0
10 – 15 1,5
15 – 20 2,0
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Under floor heating:
Pump stop function
If t e substation is used in connection wit under floor eating, t e
circulation pump must be connected to t e pump stop function in
t e under floor eating controller. T e pump must be stopped if
all under floor eating circuits are closed.
Warranty
If t is is not possible, t en flow must be continued t roug t e
by-pass. Failing t is, t e pump will be at risk of seizure and any
remaining warranty will be wit drawn.
Summer operation:
Switch off pump
In summer t e circulation pump must be switc ed off and t e
s ut-off valve to HE supply closed.
Running pump bi-weekly
It is recommended to start up t e circulation pump (for 2 minutes)
once a mont during summer; t e s ut-off valve of t e HE supply
must be s ut.
Electronic controller
Most electronic controllers will start up t e pump automatically
(please note manufacturer´s instructions).
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4.3 Electrical connections
Before making electrical connections, please note the
following:
Safety notes
Please read t e relevant parts of t e safety notes.
30 V
T e substation must be connected to 230 V AC and eart .
Potential bonding
Potential bonding s ould be carried out according
to 60364-4-41:2007 and IEC 60364-5-54:2011.
Bonding point on t e mounting plate below rig t corner marked
wit eart symbol.
Disconnection
T e substation must be electrically connected so t at it can be
disconnected for repairs.
Outdoor temperature sensor
Outdoor sensors s ould be mounted so as to avoid exposure to
direct sunlig t. T ey s ould not be placed close to doors, windows
or ventilation outlets.
T e outdoor sensor must be connected to t e station on t e
terminal block under t e electronic control.
Authorized electrician
Electrical connections must be made by an aut orized electrician only.
Local standards
Electrical connections must be made in accordance wit current
regulations and local standards.
4.3.1 Thermoactuators
Activating the thermoactuators
T e t ermoactuators are supplied wit a “first open” function, suc
t at t ey are slig tly open for frost protection until t e electrical
controller is installed. During commissioning, t e “first open”
function is disabled by removing t e red mounting split on t e
t ermoactuator.
Please c eck t at t e t ermoactuators can fully close following
disablement of t e “-first open” function.
See t e installation guide included wit t e t ermoactuator.
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5.0 Design
5.1 Design
Your substation might look different than the substation shown.
Design description
AHeat exc anger, HE 10 Circulator pump 38 Expansion tank
BHeat exc anger, DHW 14 Sensor pocket, energy meter 41 Fitting piece, energy meter
1Summer valve 20 Filling/drain valve 48 Air vent, manual
4Safety valve 26 Pressure gauge, HE 63 Sieve
7T ermostatic controller, HE 31 Differential pressure controller 74 IHPT controller, DHW
9Strainer
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5. Schematic diagram
DHW
DCW
DH
Supply
HE
Supply
DH
Return
HE
Return
Your substation might look different than the schematic diagram shown.
Schematic description
AHeat exc anger, HE 14 Sensor pocket, energy meter 38 Expansion tank
BHeat exc anger, DHW 18 T ermometer 39 Connection closed
1Ball valve 20 Filling/drain valve 41 Fitting piece, energy meter
4Safety valve 24 Delivered loose wit unit 48 Air vent, manual
7T ermostatic valve 26 Pressure gauge 63 Sieve
9Strainer 31 Differential pressure controller 74 IHPT controller
10 Circulator pump
DHW: Domestic Hot Water
DCW: Domestic Cold Water
DH Supply: District Heating Supply
DH Return: District Heating Return
HE Supply: Heating Supply
HE Return: Heating Return
5. .1 Technical parameters
Technical parameters
Nominal pressure: PN 10 (PN 16 versions are available on enquiry)
Max. DH supply temperature: 120 °C
Min. DCW static pressure: 1.0 bar
Brazing material (HEX): Copper
Heat exc angers test pressure: 30 bar
Sound level: ≤ 55 dB
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6.0 Controls
6.1 Heating circuit
6.1.1 Differential pressure controller
T e differential pressure controller smoot s out t e fluctuations in
pressure arriving from t e district eating network. T e operating
pressure in t e substation is t us eld steady.
6.1. HE temperature control
T e HE flow temperature in t e eating circuit is controlled by t e
HE temperature controller.
6.1.3 RAVK controller
RAVK controller (25-65 °C). T e temperature setting is as follows:
1 = 25 °C
2 = 35 °C
3 = 45 °C
4 = 55 °C
5 = 65 °C
The values are intended as a guide.
Thermostatic control
T e temperature of t e HE flow line is adjusted as follows:
To increase temperature, turn t e andle on t e t ermostatic
controller to select a ig er number.
To decrease temperature, turn t e andle on t e t ermostatic
controller to select a lower number.
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6.1.4 Electronic control
Substations wit electronic control must be set in accordance wit
manufacturer´s instructions.
W ere t e room temperature is controlled by radiator t ermostats,
it is recommended t at t ermostats be set for minimum
temperature in eac room.
6.1.5 Outside temperature sensor
Outdoor sensors s ould be mounted so as to avoid exposure to
direct sunlig t. T ey s ould not be placed close to doors, windows
or ventilation outlets.
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6.1.6 TP7000
TP7000 electronic 7 day programmable room t ermostat.
Signals from t e room t ermostat can be used to control zone
valves.
6.1.7 Circulator pump UPM3
UPM3 Pumps can be controlled in constant pressure, proportional
pressure or constant speed mode defined by t e means of a smart
user interface.
T e variable speed modulating modes allow t e pump to matc its
performance to t e system requirements, elping to reduce noise
w en t ermostatic valves are closing down.
Energy labelling class A
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6.1.8 Grundfos UPM3 AUTO instructions
Control mode
Eac pus on t e button switc es to t e next program setting. T e c oice of operation mode depends on t e type of eating system
and t e pressure loss in t e system.
Settings
Function: Recommended for: Green Green Yellow Yellow Yellow
Proportional pressure Auto adapt �
Constant pressure Auto adapt �
Proportional pressure 1 � �
Proportional pressure 2 2-pipe systems � � �
Proportional pressure 3 — MAX � � � �
Constant pressure 1 1-pipe systems � �
Constant pressure 2 Under floor eating � � �
Constant pressure 3 — MAX � � � �
Constant Curve 1 �
Constant Curve 2 � �
Constant Curve 3 — MAX � � �
Alarm status
Function: Recommended for: Red Green Yellow Yellow Yellow
Power Supply failure
Blocked � �
Supply voltage low � �
Electrical error � �
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6.1.9 HE pressure gauge
T e HE pressure gauge indicates t e pressure of t e HE system.
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6. DHW temperature control
DHW temperature control
T ere are various types of DHW temperature control used in
Danfoss substations.
DHW temperature s ould be adjusted to 45-50 °C, as t is provides
optimal utilisation of DH water. At DHW temperatures above 55 °C,
t e possibility of lime scale deposits increases significantly.
6. .1 IHPT 90 controller (45–65 °)
IHPT is a self-acting flow-compensated temperature controller wit
integrated differential pressure controller.
T e IHPT operates at its best at DH supply temperatures of up to
100 °C.
By turning t e andle for temperature setting in (+) direction
t e setting is increased, by turning it in (-) direction t e setting is
decreased.
Turns* Scale DHW Temperature Setting [°C]
0764
16 61
2558
34 55
43 52
52 48
61 44
70 43
*Start position Handle turned fully in (+) direction.
The values are intended as a guide.
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6.3 Other
6.3.1 Safety valve
T e purpose of t e safety valve is to protect t e substation from
excessive pressure.
T e blow-off pipe from t e safety valve must not be closed. T e
blow-off pipe outlet s ould be placed so t at it disc arges freely
and it is possible to observe any dripping from t e safety valve.
It is recommended to c eck t e operation of safety valves at
intervals of 6 mont s. T is is done by turning t e valve ead in
direction indicated.
6.3. Strainer
Strainers s ould be cleaned regularly by aut orized personnel. T e
frequency of cleaning would depend on operating conditions and
t e manufacturer’s instructions.
6.3.3 GTU Pressure Equalizer
T e GTU Pressure Equalizer absorbs t e expansion on t e
secondary side of t e Termix water eaters and can be used as a
substitute to t e safety valve.
Furt ermore t e pressure equalizer absorbs a possible increase in
pressure, so a disc arge outlet is omitted.
T e GTU Pressure Equalizer may not be applied in systems wit ot
water circulation.
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6.3.4 Fitting piece
T e substation is equipped wit a fitting piece for energy meter.
Assembly of energy meters:
1: Close ball valves
Close t e ball valves on DH Supply and DH Return, if t ere is water
on t e system.
: Loosen nuts
Loosen t e nuts on t e fitting piece.
3: Remove fitting piece
Remove t e fitting piece and replace it wit t e energy meter. Do
not forget t e gaskets.
4: Tighten connections
After mounting of t e energy meter remember to c eck and
tig ten all t readed connections.
Sensor pocket, energy meter
T e sensors of t e energy meter is mounted in t e sensor pockets.
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6.4 Extras
6.4.1 Circulation pipe
T e circulation pipe set is mounted directly on t e controller.
T e set includes circulation pipe, single c eck valve and fitting.
W en mounting t e ot water circulation directly on t e controller
t e ot water circulation temperature will be equal to t e idle
temperature. T e idle temperature is a few degrees lower t an t e
set domestic ot water temperature.
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