Danfoss Termix VVX-IV 7 Series User manual

© Danfoss | 2022.02 LGB55001
Termix VVX-IV - 7 Series DS Fully insulated
Operating Guide

2 | © Danfoss | 2022.02 LGB55001
Termix VVX-IV - 7 Series DS Fully insulated
Table of contents
Introduction..................................................................... 3
Warranty and product liability ...................................... 3
Glossary of technical terms............................................ 4
Key to symbols................................................................. 4
Materials .......................................................................... 4
Unit label.......................................................................... 5
Functional specification ................................................. 6
Personal protective equipment...........................................................6
Warning of dangerous situations that can arise with reasonably
foreseeable misuse...................................................................................6
Safety notes ..................................................................... 7
Handling, transport and storage................................... 8
Handling.......................................................................................................8
Transport and storage.............................................................................8
Assembly, installation and commissioning.................. 8
Unpacking and preparation..................................................................8
Lifting instructions ...................................................................................9
Mounting and installation ...................................................................10
Dismantling the insulation .................................................................11
Design .........................................................................................................12
Schematic description - Termix VVX-IV RAD ................................13
Schematic description - Termix VVX-IV UFH.................................14
Electrical connections and wiring ....................................................15
Wiring diagram - radiator heating....................................................16
Wiring diagram - underfloor heating..............................................16
Fitting of energy meter.........................................................................17
Commissioning........................................................................................18
Filling of the primary heating system .............................................18
Filling of the secondary heating system ........................................18
Start-up...................................................................................................... 20
Underfloor heating ............................................................................... 20
Operating Guide - Components................................... 21
Heating controls............................................................ 21
RAVK controller (35-75 °C)....................................................................21
Thermoactuators ................................................................................... 22
Differential pressure controller......................................................... 22
Circulator pump UPM3 ........................................................................ 22
Grundfos UPM3 AUTO instructions................................................. 23
IMIT Thermostat ......................................................................................24
Safety valve ...............................................................................................24
Waste adaptor..........................................................................................24
Domestic Hot Water Temperature control.................. 25
Pressure absorber .................................................................................. 25
Domestic Hot Water Re-circulation................................................. 25
Maintenance .................................................................. 27
Troubleshooting............................................................ 28
Troubleshooting..................................................................................... 29
Deactivation and dismantling ..................................... 30
Disposal.......................................................................... 30
Declaration of conformity ............................................ 31
Pre hand over check list................................................ 32

© Danfoss | 2022.02| 3LGB55001
Termix VVX-IV - 7 Series DS Fully insulated
Introduction
This heat interface unit (HIU) is intended for connecting to a heat network
for the production of both domestic hot water and space heating (HTG).
Read through the instructions before starting installation work.
Pay particular attention to the safety precautions.
The manufacturer assumes no responsibility for failure to follow the
instructions. This applies to both personal injury and product damage.
The following operating conditions must be carried out in accordance
with the directions below:
Assembly, installation and commissioning
General assembly, installation and commissioning must be
carried out by a qualified and authorised HVAC technician.
All electrical connections must be carried out by an authorised
electrician.
Daily operations
After correct installation and commissioning, under normal
circumstances further adjustment of the unit will not be
necessary.
Maintenance and cleaning
Regular maintenance of the HIU is shown in the section
“maintenance”. This section also describes the cleaning
procedures.
Dismantling
Dismantling the HIU must be carried out by an authorised
and qualified HVAC technician.
For further information regarding disposal, please refer to the
section “disposal”.
Warranty and product liability
Danfoss A/S’ area of responsibility does not include balancing, scope of
works or mounting and correct connection of the unit.
If changes are carried out to the HIU’s configuration or structure, the
manufacturer can assume no responsibility.
The warranty does not cover incorrect use of the product.

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Termix VVX-IV - 7 Series DS Fully insulated
Key to symbols
Glossary of technical terms
DHW Domestic hot water
DCW Domestic cold water
HWC Hot water circulation
DHF Heat network supply
DHR Heat network return
HFL Heating supply
HRL Heating return
Materials
Corrosion protection
All pipes and components are manufactured in stainless steel and brass.
The chloride content in the flow medium should not exceed 150 mg/l.
The risk of corrosion increases significantly if the recommended chloride
content is exceeded.
REACH
All products from Gemina Termix A/S meet the requirements in REACH.
One of the requirements in REACH is to inform customers of any content
of materials on the REACH candidate list. We hereby inform customers
of a material on the candidate list. The product contains brass parts,
which contain lead (CAS no: 7439-92-1) in a concentration over 0.1% w/w.
Heat network
Space heating
Underfloor heating
Circulation
Domestic hot water
Domestic cold water

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Termix VVX-IV - 7 Series DS Fully insulated
Unit label
The unit label is affixed to the back plate
(Image of a unit label is shown as an example).
Should the unit label become unreadable, damaged or fall off completely,
then it must be replaced.
New unit label can be ordered.

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Termix VVX-IV - 7 Series DS Fully insulated
Functional specification
The HIU is intended for connecting to a heat network for the production of
both domestic hot water and space heating.
The unit must be connected to the household installation in a frost-free
location.
Technical specifications
Specifications:
Max. working pressure: See the unit label on the HIU
Max. temperature: See the unit label on the HIU
Power connection: 230 V AC
Sound level: ≤ 55 dB
Ambient temp: 0 - 40°C
(in continuous use)
Dimensions for connections:
DHF + DHR + HFL + HRL + DCW + DHW: G ¾” (internal thread)
Weight:
Net weight: 24 - 29 kg
Dimensions:
Dimensions: H 710 mm x W 530 mm x D 270 mm
The recommended operational parameters must not be exceeded.
Gloves
It is recommended that suitable work
gloves are used in connection with
handling and lifting of the HIU.
Personal protective equipment
Warning of dangerous situations that can arise with reasonably foreseeable misuse
The risk of personal injury or product damage increases considerably if the
recommended operational parameters are exceeded.
The unit must always be equipped with safety valves in accordance with
local regulations.

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Termix VVX-IV - 7 Series DS Fully insulated
Safety notes
Authorised personnel
Assembly, installation, commissioning and maintenance must
only be carried out by a qualified and authorised HVAC or electrical
technician.
Read the instructions before start-up
The instructions must be read through before installation
a n d c o m m i s s i o n i n g o f t h e u n i t . P a y p a r t i c u l a r a t t e n t i o n
to the section on safety precautions.
The manufacturer assumes no responsibility for failure to follow
the instructions. This applies to both personal injury and product
damage.
Installation requirements
The unit must be connected to the household installation in a
frost-free location.
Hanging and fastening
It must be ensured that both the wall and the fastenings of the unit
can bear the unit’s gross weight.
Heat source
The unit is designed for connection to heat network.
An alternative energy source can be used as long as the operating
conditions are equivalent to heat network at all times.
Handling
All lifting and handling of the HIU must be carried out in an
ergonomically responsible manner.
Lifting the unit
When lifting the HIU, only lift by the pipes that are fixed to the back
plate. Otherwise, to the extent possible, the HIU must be lifted by the
back plate.
Please refer to the section “Lifting instructions”.
Re-tightening
As the unit has been subjected to vibrations during transport and
lifting/handling it is important that all union connections are re-
tightened.
After filling the system with water and once it is in operation, all
union connections must be re-tightened again.
Modifications
Modifications to the electrical connections on the HIU may only be
carried out by an authorised electrician.
If changes are carried out to the HIU’s configuration or structure, the
manufacturer can assume no responsibility.
Resistance to water on electrical equipment
Electrical components are not protected against water ingress.
Safety valve
A safety valve(s) must always be fitted in accordance with local
regulations.
Connection
The possibility to shut off all energy sources to the HIU at all times
must be established, including the electrical connection.
It must be ensured that wires and cables do not come into contact
with the hot pipes. It must also be ensured that wires and cables are
not placed against sharp edges.
Warning of high pressure and temperatures
Particular attention must be given to the installation’s permitted
system pressure and operating temperature.
The maximum permitted flow temperature and pressure are stated
on the unit label.
The risk of personal injury or product damage increases considerably
if the recommended operational parameters are exceeded.
Warning of hot surfaces
Particular attention must be given to hot surfaces, as these can cause
burns to the skin.
Warning of sharp edges
It is recommended that suitable work gloves are used in connection
with handling and lifting of the HIU.

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Termix VVX-IV - 7 Series DS Fully insulated
Handling, transport and storage
Handling
A l l l i f t i n g a n d h a n d l i n g o f t h e H I U m u s t b e c a r r i e d o u t i n a n e r g o n o m i c a l l y
responsible manner.
Transport and storage
The unit must be properly packed during both transit and storage.
Transport temperature: -10 to +65°C
Storage temperature: +10 to +65°C
When storing the unit prior to installation, it must be stored in a dry,
heated place.
If more units are supplied at the same time, they must never be stacked
higher than they were at the factory.
Assembly, installation and commissioning
Unpacking and preparation
Remove the packaging from the unit.
Cling film and cardboard must be disposed of in accordance with locally
applicable legislation.
Authorised personnel
Assembly, installation and commissioning must only be carried out
by an authorised HVAC technician.
Lifting the unit
When lifting the unit out of the cardboard box, only lift by the pipes
that are attached to the back plate.
Otherwise, to the extent possible, the HIU must be lifted by the back
plate.
In connection with assembly, the unit must be lifted according to
the section “lifting instructions”.
Warning of transport damage
Before installing the unit, check to ensure the product has not been
damaged during transit.

© Danfoss | 2022.02| 9LGB55001
Termix VVX-IV - 7 Series DS Fully insulated
Lifting instructions
Temporarily remove the inspection hatch.
Temporarily remove the service hatch.
Lift the HIU in the following two places:
1. On the left hand side around the DHR pipe.
2. On the right hand side around the pipe below T-piece attached to the
heat exchanger.
Now, hang the HIU onto bolts in the wall.

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Termix VVX-IV - 7 Series DS Fully insulated
Mounting and installation
Hanging and fastening
It must be ensured that both the wall and the fastenings of the unit
can bear the unit’s gross weight.
Please refer to the section “Technical specifications”.
Re-tightening
As the unit has been subjected to vibrations during transit it is
important that all screw fittings are re-tightened.
The existing installation should be flushed out prior to installation.
Follow the symbols indicated on the HIU for correct connection of the
pipes. Please refer to the section “Key to symbols”.
Adequate space
Please allow adequate space around the HIU for mounting and
maintenance purposes.
Orientation
The unit must be mounted so that components, keyholes and labels are
placed correctly. If you wish to mount the unit differently please contact
your supplier.
Mounting
The unit is designed for wall mounting using the 2 × keyholes on the
backplate of the unit.
Additional holes for wall mounting to allow the HIU to be flush with the
wall.
Installation must comply with local standards and regulations.
Tightening
Due to vibrations during transit, lifting and handling all HIU connections
must be checked and tightened before installation.

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Termix VVX-IV - 7 Series DS Fully insulated
Dismantling the insulation
Disassembly of the side frame
Disassembly of the inspection- and servicehatch

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Termix VVX-IV - 7 Series DS Fully insulated
Design
A Heat exchanger, HTG 10 Circulator pump 48 Air vent, manual
B Heat exchanger, DHW 14 Sensor pocket, energy meter 62B Pressure absorber with non-return valve
M Electrical wiring box 20 Filling/drain valve 63 Sieve
2B Double check valve 31 Differential pressure controller 69 On/off valve
4 Safety valve 38 Expansion tank 74 IHPT controller, DHW
7 Thermostatic valve, HTG 41B Fitting piece, energy meter
9 Strainer 41C Fitting piece, Shut-off-valve
Your HIU may look different from the HIU shown
Heating flow and return pipes will be fitted as top feed or bottom feed, according to specification

© Danfoss | 2022.02| 13LGB55001
Termix VVX-IV - 7 Series DS Fully insulated
Schematic description - Termix VVX-IV RAD
A Heat exchanger, HTG 9 Strainer 41B Fitting piece, energy meter
B Heat exchanger, DHW 10 Circulator pump 41C Fitting piece, Shut-off-valve
L Border of delivery 14 Sensor pocket, energy meter 48 Air vent, manual
M Electrical wiring box 20 Filling/drain valve 62B Pressure absorber with non-return valve
1 Isolation valve 26 Pressure gauge 63 Sieve
2B Double check valve 31 Differential pressure controller 69 On/Off valve
4 Safety valve 38 Expansion tank 74 IHPT controller, DHW
7 Thermostatic valve, HTG 39 Connection closed
Your HIU may look different from the HIU shown
Heating
Supply
Heating
Return
Domestic
Hot Water
Domestic
Cold Water
Heat Network
Supply
Heat Network
Return
Mounting rail

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Termix VVX-IV - 7 Series DS Fully insulated
Schematic description - Termix VVX-IV UFH
A Heat exchanger, HTG 10 Circulator pump 41C Fitting piece, Shut-off-valve
B Heat exchanger, DHW 14 Sensor pocket, energy meter 48 Air vent, manual
L Border of delivery 20 Filling/drain valve 60 Thermostat (only for UFH)
M Electrical wiring box 24 Delivered loose with unit 62B Pressure absorber with non-return valve
1 Isolation valve 26 Pressure gauge 63 Sieve
2B Double check valve 31 Differential pressure controller 69 On/Off valve
4 Safety valve 38 Expansion tank 74 IHPT controller, DHW
7 Thermostatic valve, HTG 39 Connection closed
9 Strainer 41B Fitting piece, energy meter
Your HIU may look different from the HIU shown
Heating
Supply
Heating
Return
Domestic
Hot Water
Domestic
Cold Water
Heat Network
Return
Mounting rail
Heat Network
Supply

© Danfoss | 2022.02| 15LGB55001
Termix VVX-IV - 7 Series DS Fully insulated
Electrical connections and wiring
Before connecting the unit to an electrical supply, please note the
following:
Safety notes
Please read the relevant parts of the safety notes.
230 V
The HIU must be connected to 230 V AC and earth.
Potential bonding
Potential bonding should be carried out according
to DS/HD 60364-4-41:2007 and IEC 60364-5-54:2011.
Disconnection
The electrically connected HIU must be disconnected for repairs.
Wires and cables
It must be ensured that wires and cables do not come into contact with
the hot pipes. It must also be ensured that wires and cables are not placed
against sharp edges.
Authorised personnel
All electrical installation work may only be carried out by an
authorised electrician.
The electrical connection must be carried out in accordance
with applicable legislation and local standards.

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Termix VVX-IV - 7 Series DS Fully insulated
Wiring diagram - underfloor heating
Wiring diagram - radiator heating

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Termix VVX-IV - 7 Series DS Fully insulated
Fitting piece
The HIU is equipped with a fitting piece for the energy meter.
Mounting the energy meters:
• Close isolation valves
Close the isolation valves on Heat network supply and Heat network
return, if there is water in the system.
• Loosen nuts
Loosen the nuts on the fitting piece.
• Remove fitting piece
Remove the fitting piece and replace it with the energy meter. Don´t
forget the gaskets.
• Tighten connections
After mounting of the energy meter, remember to check and tighten all
threaded connections.
Sensor pocket
The sensors of the energy meter is mounted in the sensor pockets.
41
see diagram
14
see diagram
Fitting of energy meter

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Termix VVX-IV - 7 Series DS Fully insulated
Filling of the primary heating system
First fill
When carrying out the first fill, the heat exchanger must be slowly filled
with water until it reaches working pressure.
Pressure gauge
The HTG pressure gauge indicates the pressure of the HTG system. This
instruction must be followed strictly to avoid dangerous situations.
Supply hose
An isolation valve with plug is installed in the HTG return line. To fill the
system, the isolation valve must first be closed, the plug removed and a
supply hose connected. On re-opening the isolation valve, system fill can
commence.
Filling stop
When filling the system with water, the pressure gauge should be observed
closely. Filling must stop when the pressure gauge shows a pressure
approximately 1-2 bar higher than the pre-pressure setting. The isolation
valve is then closed, the hose removed and the plug replaced.
Pre-pressure
The expansion vessel is supplied prepressurised to 0.5 bar. The
pre-pressure required for the individual HIU will depend on system head
(the distance between the lowest and highest point in the system), for
example:
Height (m) Presssure (bar)
0-5 0,5
5-10 1,0
10-15 1,5
15-20 2,0
Re-tighten connections
After water has been added to the system and the system has been
put into operation, re-tighten ALL connections.
26
see diagram
Filling of the secondary heating system
A flushing bypass or similar should be mounted.
Only introduce heating network water in the HIU once it has been flushed.
Commissioning
Before start-up check that:
• Pipes are connected in accordance with the symbols indicated on the
HIU.
• Then slowly open the isolation valve(s) so that the HIU fills with water.
• Ensure that all union fittings and swivel nuts have been re-tightened.
• The heating circuit must be vented before commissioning.
• Monitor the HIU’s operation in regard to temperature, pressure, thermal
expansion and leaks.
• Provided the HIU functions in accordance with the dimensioning
regulations, it can be put into use.

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Termix VVX-IV - 7 Series DS Fully insulated
Step 1:
Remove the inspection hatch and service hatch.
Step 2:
Remove the cap and connect the flexible hose.
Step 3:
Open both valves.
Step 4:
After filling up the secondary heating system, close both valves,
disconnect the flexible hose and refit the insulation.

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Termix VVX-IV - 7 Series DS Fully insulated
Underfloor heating
Pump stop function
If the HIU is used in connection with underfloor heating, the circulation
pump must be connected to the pump stop function in the underfloor
heating controller. The pump must be stopped if all underfloor heating
circuits are closed.
Warranty
If this is not possible, then flow must be continued through the by-pass.
Failing this, the pump will be at risk of seizure and any remaining warranty
is forfeited.
Start pump
Start the pump and adjust to its highest speed.
Remark:
The circulator pump should run for 10 minutes during the first installation.
Open isolation valves - primary
The isolation valves should then be opened and the unit observed as it
enters service. Visual checking should confirm temperatures, pressures,
acceptable thermal expansion and absence of leakage. If the heat
exchanger operates in accordance with design, it can be put into regular
use.
Vent system
Switch off the pump and vent the installation after the radiators have
warmed up.
Pump settings
Adjust pump to recommended pump settings.
Check the strainer
Check strainer on primary heating and space heating.
Strainers should be cleaned regularly by authorized personnel. The
frequency of cleaning will depend on operating conditions.
Start-up
Pump
The pump must be switched off during system filling.
09
see diagram