CTC Union GSi 16 Manual

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Installation and Maintenance Manual
CTC GSi 16
Modulating ground source heat pump
400V 3N~
IMPORTANT
READ CAREFULLY BEFORE USE
KEEP FOR FUTURE REFERENCE
162 205 94-1 06/02/2019

(10 x)
1 2
3
1, 2, 3
1, 2, 3
3
!
162 201 99-1 2015-09-14
1. Disconnect the cooling module’s power cable connector and hoses.
2. Attach the two carrying handles to the bottom of the cooling module.
3. Unscrew the cooling module’s screws. 4. Pull the cooling module by first lifting the front edge
slightly with the carrying handles.
5. Lift the cooling module using the carrying handles and
shoulder straps.
6. Lift the cooling module into the product using the
carrying handles and shoulder straps. Remove the
carrying handles and reconnect the power cable,
hoses and screws.
Removing the cooling module
• Any work done on the product’s cooling system should be done by authorised personnel only.
• Close the safety switch before doing any work on the product.

Installation and Maintenance Manual
CTC GSi16
Modulating ground source heat pump
400V 3N~
162 205 94-1 06/02/2019

4CTC GSi 16
Important! Information on
air bleeding
For the product to work as intended, the system must be
fully bled.
It is extremely important that a basic bleeding of the product is carried out
systematically and carefully.
Bleeding devices must be fitted to the system’s natural high points. A basic
bleeding of the hot water tank can be carried out upon installation by releasing
the safety valve, which must be fitted to the top of the product.
The water must be circulated during bleeding of the various subsystems: the
radiator systems, heat pump system and hot water charging system (to run
the pumps, diverting valve etc. manually, go into the menu Installer/Service/
Function test). Also move the diverting valve during the bleeding process.
A careful basic bleeding must be carried out before the system is put into
operation and the heat pump is started.
Tip:
Once basic bleeding is complete: increase the water pressure in the system
temporarily to approx. 2 bar.
Automatic bleeding valves are included in the package and supplied as
standard for this product. They must be fitted to the top of the product as
shown in the picture.
Important! Bleed any air remaining in the radiators (elements) and other parts
of the system after it has been in operation for a short time.
Small microbubbles gradually collect in the system’s “pockets”, and it can
take quite a long time before all the air is removed from the system. When the
pressure is temporarily increased, any remaining air pockets are compressed
and carried along more easily with the flow of water, and can be released into
the ventilation devices.
Tip:
After the air is bled, there may be a drop in system pressure. Having the
system pressure too low increases the risk of noise in the system and of air
being “sucked” in on the suction side of the pump. Keep an eye on the system
pressure. Bear in mind that the system pressure will vary in the course of the
year due to changes in temperature in the heating circuit, which is completely
normal.
If “gushing” sounds can be heard from the product, this is a sign of remaining
air.
A loss of heating functionality can also be a sign of remaining air.
The automatic bleeding
valves are equipped
with shut off screws.
!Information in this type of box [!] is particularly important for correctly installing
and using the product.
iInformation in this type of box [i] is intended to help ensure that the product
functions optimally.
General Information

5CTC GSi 16
Table of Contents
Important! Information on air bleeding ______________________ 4
Your home’s heating settings______________________________________ 9
1. Technical data _____________________________________________________ 12
1.1 Operating range CTC GSi16_____________________________ 14
2. Design __________________________________________________________________ 16
3. Parameter list ______________________________________________________ 17
4. Important to remember! _____________________________________ 20
4.1 Transportation__________________________________________________ 20
4.2 Positioning ______________________________________________________20
4.3 Recycling ________________________________________________________20
4.4 After commissioning_________________________________________ 20
5. Installation____________________________________________________________ 21
5.1 Unpacking_______________________________________________________ 21
5.2 Control functions (std.) and with
Expansion Card _______________________________________________ 22
6. Pipe installation___________________________________________________ 23
6.1 Schematic diagram __________________________________________23
7. Connecting the brine system_____________________________ 34
7.1 Connections____________________________________________________ 34
7.2 Brine system schematic diagram _______________________37
7.3 Coolant pump (G20)_________________________________________39
8. Electrical installation___________________________________________ 40
8.1 Sensor connection ___________________________________________42
8.2 Checking connected sensors ____________________________ 43
8.3 Pressure/level switch ________________________________________43
8.4 Installing a backup power supply _______________________ 43
8.5 Pump Diff thermostat function (G46) on/off _________ 43
8.6 Heating circuit 2 (alt. Free cooling)______________________44
8.7 Pool (accessory) ______________________________________________45
8.8 External heat source (EHS)________________________________ 45
8.9 CTC EcoVent (accessory)__________________________________ 45
8.10 CTC SmartControl (accessory) __________________________45
8.11 Solar heat (accessory) ______________________________________ 46
8.12 Current sensor connection (accessory)_______________ 47
8.13 Tank schematic diagram (A2)_____________________________ 48
8.14 HP cooling module schematic diagram (A5) ________ 50
8.15 Expansion card (accessory)
schematic diagram (A3) ____________________________________52
8.16 Parts list__________________________________________________________ 55
8.17 Resistance for sensor 1(2)_________________________________ 56
8.18 Resistance sensor 2(2) _____________________________________ 57
9. First start______________________________________________________________ 58
10. Operation and Maintenance ______________________________ 60
11. Menu overview ____________________________________________________ 62
12. Detailed menu descriptions _______________________________ 64
12.1 Start menu ______________________________________________________64
12.2 Room temperature ___________________________________________65
12.3 DHW ______________________________________________________________ 67
12.4 Operation________________________________________________________ 68
12.5 Installer ___________________________________________________________ 75
12.6 Heat pump ______________________________________________________80
12.7 Electric heater__________________________________________________ 82
12.8 DHW tank _______________________________________________________83
12.9 Communication _______________________________________________ 85
12.10 Cooling ___________________________________________________________ 86
12.11 Solar panels (accessories)_________________________________ 87
12.12 Diff thermostat function_____________________________________ 93
12.13 Pool (accessory) ______________________________________________ 94
12.14 External heat source (EHS)________________________________95
12.15 EcoVent (accessory) _________________________________________ 95
12.16 Define system__________________________________________________ 96
12.17 Define remote control _____________________________________ 100
12.18 Remote control procedure ______________________________ 100
12.19 Smart Grid ____________________________________________________ 103
12.20 Service_________________________________________________________ 106
13. Troubleshooting/appropriate measures _________ 112
13.1 Information messages ____________________________________ 115
13.2 Alarm messages ____________________________________________ 117

6CTC GSi 16

7CTC GSi 16
Congratulations on your new product
You have just purchased a CTCGSi16, with which we
hope you will be very pleased. Read about how you can
take care of your heat pump on the following pages.
Save this manual containing the installation and
maintenance instructions. If properly maintained, you will
be able to enjoy the use of your CTC GSi 16 for many
years. This manual will provide all the information you
will need.
The complete heat pump
CTC GSi 16 is a complete heat pump able to meet the
heating and hot water requirements of your home. It has
a built-in, energy-efficient (A rated) circulation pump for
connection to the ground/bedrock circuit, i.e. the cold
side. This can be connected to either the left, right or
back of the heat pump, whichever suits you best.
CTC GSi 16 has a control system which:
• Monitors all heat pump functions
• Permits individual settings
• Displays desired values, such as temperatures,
operation times, energy consumption and fault
signals
• Facilitates the setting of values and troubleshooting
in a simple and well-structured way
The built-in heat exchanger provides copious amounts
of hot water. CTC GSi 16 also has a so-called summer-
time basement heating function and a floor heating
block, which maximises the temperature supplied to
the floor circuits. Using the integrated night reduction
function, you can set and change the temperature in the
house throughout the day, from one day to the next.
Its easily accessible electrical components and cooling
module, along with effective troubleshooting functions in
the control program, make CTC GSi 16 easy to service.
If you want to supplement your CTC GSi 16 with other
sources of heating, you can do this easily. We have
decided to call this option Energyflex. With Energyflex
you can, for example:
• Charge your heating circuit with solar energy
• Allow a water-jacketed stove to contribute heat
• Connect a pool heat exchanger to heat up a
swimming pool
NB:
This installation manual provides
information on technical data, operation,
installation, etc. Local regulations or
country-specific regulations must be
taken into account.

8CTC GSi 16
Safety instructions
Turn off the power with an omnipolar switch before doing any work on the product.
The product must be connected to protective earth.
The product is classified as IPX1. The product must not be rinsed with water.
When handling the product with a hoist ring or similar device, make sure that the
lifting equipment, eyebolts and other parts are not damaged. Never stand under the
hoisted product.
Never jeopardise safety by removing bolted covers, hoods or similar.
Any work on the product’s cooling system should be carried out by authorised
personnel only.
The product’s electrical systems should only be installed and serviced by a qualified
electrician.
-If the supply cord is damaged, it must be replaced by the manufacturer, its service
agent or similarly qualified persons in order to avoid a hazard.
Safety valve check:
-Safety valve for boiler/system to be checked regularly.
The product must not be started if it is not filled with water; instructions are in the
“Pipe installation” section.
WARNING: Do not switch on the product if there is a possibility that the water in the
heater is frozen.
This device can be used by children from the age of eight years and above and by
people with reduced physical, sensory or mental ability or lack of experience or
knowledge if they have been taught, either with supervision or with the instructions
provided, how to use the device safely and understand the risks involved. Children
should not play with the device. Cleaning and maintenance should not be carried
out by children without supervision.
If these instructions are not followed when installing, operating and maintaining the
system, Enertech’s commitment under the applicable warranty terms is not binding.

9
CTC GSi 16
iThe set heating curve always takes priority. The room sensor can only increase
or decrease the heat beyond the set heating curve to a certain extent. Where
operating without a room sensor, the selected heating curve determines the
flow temperature supplied to the radiators.
The House Heating Curve
The heating curve is the central part of the product’s control system. It is the heating
curve which determines the compensated flow temperature requirements for your
property dependent upon the outdoor temperatures. It is important that the heating
curve is correctly adjusted, so that you achieve the best operation and economy
possible.
One property requires a radiator temperature of 30°C when the outdoor temperature
is 0°C, whilst a different property requires 40°C. The difference between different
properties is determined by the radiator surface area, the number of radiators and how
well insulated the house is.
Adjustment of Default Values for the Heating Curve
You define the heating curve yourself for your property by setting two values in
the product control system. This is achieved by selecting the options Inclination or
Adjustment under the Installer/Settings/Radiator system menu. Ask your installer to
help you set these values.
It is extremely important to set the heating curve and, in some cases, unfortunately,
this process may take several weeks. The best way of doing this, upon the initial
start-up, is to select operation without any room sensor. The system then operates
using the outdoor temperature reading and the property’s heating curve only.
During the adjustment period it is important that:
• the night reduction function is not selected.
• all thermostat valves on the radiators be fully opened. (This is to find the
lowest curve for the most economical use of the heat pump.)
• the outdoor temperature is not higher than +5°C. (If the outdoor
temperature is higher when the system is installed, use the factory set
curve until the outdoor temperature falls to a suitable level.)
• the radiator system is operational and correctly adjusted between different
circuits.
Appropriate Default Values
During installation you can seldom achieve a precise setting for the heating
curve instantly. In this case, the values given below may provide a good starting
point. Radiators with small heat-emission surfaces require a higher primary flow
temperature. You can adjust the gradient (heating curve gradient) for your heating
system under the Installer/Settings/Radiator system menu.
Recommended values are:
Floor heating only Inclination 35
Low temperature system (well insulated houses) Inclination 40
Normal temperature system (factory setting) Inclination 50
High temperature system
(older houses, small radiators, poorly insulated) Inclination 60
Your home’s heating settings

10 CTC GSi 16
Examples of Heating Curves
You can see in the diagram below how the heating curve
changes with different Inclination settings. The gradient of
the curve shows the temperatures that the radiators require
at different outdoor temperatures.
Curve Inclination
The inclination value which is set is the primary flow
temperature when the outside temperature is –15°C.
Primary Flow Temperature
Primary Flow Temperature
Primary Flow Temperature
Outside Temperature
Outside Temperature
Heating off, out
Outside Temperature
Adjustment
The curve can be parallel displaced (adjusted) by the
desired number of degrees to adapt to different systems/
houses.
An example
Inclination 60°C
Adjustment 0°C
In this example, the maximum outgoing primary flow
temperature is set at 55°C.
The minimum permitted primary flow temperature is 27°C
(e.g. summer-time basement heating or the floor circuits in
a bathroom).
Inclination 50°C
Adjustment +5°C
Inclination 50°C
Adjustment 0°C
Heating off, out

11
CTC GSi 16
ºC
ºC
Summer-time operation
All properties have internal heat gains (lamps, oven,
body heat, etc.), which means that the heating can be
switched off when the outdoor temperature is lower
than the desired room temperature. The better insulated
the house is, the earlier the heating from the heat pump
can be switched off.
The example shows the product set at the default value
of 18°C. This value, "Heating off, outside", can be
changed in the Advanced/Settings/Heat System menu.
In systems with a radiator pump, the radiator pump
stops when the heat is switched off. The heating starts
up automatically when it is required again.
Automatic or remote-controlled summer period
The factory setting causes "summer" to commence
automatically at 18ºC, as "Heating mode" is set to
"Auto".
Heating,mode Auto (Auto/On/Off)
Auto means automatic.
On means that the heating is on. For systems with
a mixing valve and a radiator pump, the mixing valve
operates to the primary flow setpoint and the radiator
pump is on.
Off means that the heating is switched off. For systems
with a radiator pump, the radiator pump is switched off.
Heating, ext. mode - (- /Auto/On/Off)
Facility for remote control of whether the heating is to be
on or off.
Auto means automatic.
On means that the heating is on. For systems with
a mixing valve and a radiator pump, the mixing valve
operates to the primary flow setpoint and the radiator
pump is on.
Off means that the heating is switched off. For systems
with a radiator pump, the radiator pump is switched off.
- No selection means no function when activated.
Heating up
Outside Temperature
Heating off, out
Primary Flow Temperature Heating
switched
off

12 CTC GSi 16
400V 3N~ 50 Hz
kW 7.0
A1.8
kW 9
kW - / 0.3 / 0.9 / 2.1 / 9
A11.1
A25
Ω0.13
IP X1
HP Keymark Cert. No. 012-SC0819-18
l 229
bar 3.0
°C 100
l/s 0.52
kW 16
@ 0/35 | 0/45 | 0/55 kW 10.52 I 9.58 I 8.90 @50 rps
@ 0/35 | 0/45 | 0/55 kW 2.34 I 2.80 I 3.27 @50 rps
COP 1) @ 0/35 | 0/45 | 0/55 - 4.50 I 3.43 I 2.72 @50 rps
@ 5/35 | 5/45 | 5/55 kW 12.26 I 11.22 I 10.55 @50 rps
COP 1) @ 5/35 | 5/45 | 5/55 - 5.07 I 3.87 I 3.14 @50 rps
SCOP 0/35 Pdesign cold climate 2) Pdesign = 16 kW, SCOP = 5.5
SCOP 0/55 Pdesign cold climate 2) Pdesign = 16 kW, SCOP = 4.22
SCOP 0/35 Pdesign average climate 2) Pdesign = 16 kW, SCOP = 5.2
SCOP 0/55 Pdesign average climate 2) Pdesign = 16 kW, SCOP = 4.0
Electrical data
Electrical data
Rated power
Max starting current
Immersion heater (steps of 0,3 kW)
1)
Max immersion heater output
@ fuse size 10 / 16 / 20 / 25 A
1)
Max. operating current Compressor
Fuse, max.
Maximum permitted impedance at connection*
Ingress Protection (IP)
Heating system
Water volume (V)
Max. operating pressure boiler (PS)
Max. temperature boiler (TS)
Heating system nominal flow @50 rps
Pressure drop See diagram in chapter Pipe installation
Operational data for heat pump
Max output from compressor
Output from compressor 1)
Input power 1)
1) EN14511:2018
2) SCOP according to FprEN14825
* Maximum permitted impedance at the mains connection according to EN 61000-3-12.
If the impedance at the mains connection is higher than the specified, check with the
grid owner before purchasing the equipment.
1) Max. 6 kW electric heater output in combination with compressor operation.
1. Technical data

13
CTC GSi 16
Ω
mm 28
mm 22
mm 22
mm 22
kg 2.2
ton 3.903
MPa 3.1
kg 300 / 275
mm 673 x 596 x 1910
mm 1940
dB(A) 36/40
l 4.1
°C -5 / +20
bar 0.2/3.0
l/s 0.29
l/s 0.39
l 1.7
bar 10
°C 100
l 210 / 235 / 304
2.81 (XL) / 2.47 (XL) / 2.25 (XL)
Other data
Refrigerant quantity (R407C, fluorinated
greenhouse gases GWP 1774)
CO2equivalent
Interrupt value switch HT
Weight with/without packaging
Dimensions (Depth x Width x Height)
Required ceiling height
Noise level (LWA) according to EN 12102 @30/35 °C
Brine system
Water volume (V)
Brine system min/max temp (TS)
Brine system min/max pressure (PS)
Brine system min flow
Brine system nominal flow, ∆t=3 K @50rps
Pump capacity See diagram in chapter Pipe installation
DHW system
Water volume (V)
Max operating pressure (PS)
Max operating temperature (TS)
DHW capacity according to. prEN16147 Economic/Normal/Comfort
DHW capacity
COP/ (Tapping cycle)
No annual leakage control of the refrigerant is required
Pipe connections
Brine circuit, ext. diam. Cu piping (flexible hose)
Heating medium, ext. diam. Cu piping
Hot water supply, ext. diam.
Cold water supply, ext. diam.

14 CTC GSi 16
0
10
20
30
40
50
60
70
-10 -5 0 5 10 15 20
twi
two
twi
two
twºC
tci ºC
1.1 Operating range CTC GSi16
Operating range is based on normal operating conditions and may therefore
be different in different installations.
(tci = temperature brine in)
Primary flow temperature (two) °C
Return temperature (two) °C
T fra
T fra
T re
T re

15
CTC GSi 16
1910
1881 1798
633
673
355
54
Expansionsanslutning/ Lyftmu G 3/4”
55
125
596
50
106 137
297
298
Expansionsanslutning/ L
1. Cold water Ø22
2. DHW Ø22
3. Return Ø22
4. Primary flow Ø22
5. Expansion connection/ Lifting sleeve G
3/4”
6. Bleed valve connection G 1/2”
1 3 4
5
2
6

16 CTC GSi 16
2. Design
The picture below shows the fundamental construction of the heat pump.
The energy in the bore hole (bedrock) or ground is drawn up by the cooling
system. The compressor then increases the temperature to a usable level.
Afterwards it releases the energy for the heating circuit and DHW.
Tap water connections
The property’s tap water
connections are connected
here.
Radiator connections
The property’s heating
system is connected here.
DHW heat exchanger
The heat pump is equipped with a
stainless heat exchanger.
Direct heating of hot water
minimises the risk of legionella
bacteria.
Flow heater
There is an immersion heater for
additional heating here.
3-way valve
Flow conditioner.
Terminal block for sensors
The sensor terminal block is
connected internally. Outdoor
sensors, room sensors and
other sensors are connected
easily here.
Display (A1)
Junction box (A5)
Module
Circulation pump, DHW
Charge pump (G5) for DHW
Max. thermostat (F10)
Charge pump (G11)
Pump for the hot side (concealed,
placed behind the electrical
connection box)
Brine pump (G20)
Circuit breakers (F2)
Circuit breakers (F1)
Junction box (A2)

17
CTC GSi 16
60
18
120
50
0
5
-2
-3
5
1
2
20
60
25
5.5
0
-500
-50
20
3x400V
-60
80
50
5
30
70
10
10
4
15
7
3
60
70
5
22
1.0
20
50
1
2
25.0
1
2
Heating circuit Factory
settings
User value
Max primary flow ºC
Min primary flow ºC Off
Heating, mode Auto
Heating, mode, ext Off
Heating off, out ºC
Heating off, time
Inclination ºC
Adjustment ºC
Night reduction disable ºC
Room temp reduced ºC
Primary flow reduced ºC
Alarm room temp ºC
Smart low price ºC
Smart over capacity ºC
Max time heating
Charge pump %
Drying period mode Off
Drying period temp ºC
Electric heater Factory
settings
User value
Max el. heater kW
Max el. heater DHW kW
Start at degree minute
Diff step, degree minute
Main fuse A
Input voltage
Tariff EL Off
Smart block immersion Off
Heat pump Factory
settings
User value
Tariff HP Off
Smart block HP Off
Start at degree minute
Max RPS
Max RPS silent mode
DHW tank Factory
settings
User value
Program DHW
Start/stop diff upper ºC
Max time DHW
Charge pump %
Smart low price ºC
Smart overcapacity
Runtime DHW-circ.
Time DHW-circ.
Diff thermostat function Factory
settings
User value
Charge start diff temp ºC
Charge stop diff temp ºC
Charge temperature ºC
External heat source Factory
settings
User value
Charge start ºC
Start/ stop diff.
Smart block cap. Off
Pool Factory
settings
User value
Pool temp °C
Pool diff °C
Max time Pool
Charge pump %
Smart low price ºC
Smart overcapacity ºC
Cooling Factory
settings
User value
Common Heating and Cooling Yes
Condense Secured? No
Room temp cooling
Smart low price ºC
Smart overcapacity
3. Parameter list

18 CTC GSi 16
Factory setting Min Max
Adapted (RPS) 100 10 100
Forced (RPS) 80 10 100
Normal (RPS) 50 10 100
Reduced (RPS) 20 10 100
Run-on time (minutes) 30 600
Time until filter change (d) 90
Night cooling
Start diff room
Stop diff room
Diff. inside/outside (hard-coded)
No
3 °C
1 °C
3 °C
1
0
-
10
10
-
Weekly program Off
Parameter list - Ventilation

19
CTC GSi 16
60
70
60
70
60
30
18
7
3
60
7
3
20
4 / 30
6.0
120
50
-25
60
70
EcoTank Factory
settings
User value
Charge temperature ºC
Maximum tank temp ºC
X-volume Factory
settings
User value
Charge temperature ºC
Maximum tank temp ºC
Recharging of bedrock Factory
settings
User value
Recharging active No
-Charge start diff temp °C
-Charge stop diff temp °C
-Max brine temperature °C
Charging EHS-tank Factory
settings
User value
Charge start diff temp °C
Charge stop diff temp °C
Charge tank temp °C
Solar panels Factory
settings
User value
Charge start diff temp °C
Charge stop diff temp °C
Charge pump min %
Sensor test active No
-Test/Paus, min
-Winter break No Nov- Feb
Prioritize charging EHS-tank
Flow l/min
Over temp protection panel No
-Max panel temp °C
Cool over temp in tank No
-Tank cooled down to °C
Antifreeze protection panel No
-Active when panel temp °C
Prioritize protection EHS-tank
Settings EHS-tank Factory
settings
User value
Charge temperature ºC
Maximum tank temp ºC
Parameter list - Solar panels

20 CTC GSi 16
4. Important to
remember!
Check the following in particular on delivery and installation:
4.1 Transportation
Transport the unit to the installation site before removing the packaging.
Handle the product in the following manner:
• Forklift
• Lifting eye that has been fitted to the lifting sleeve on top of the product
in the expansion connection.
• Lifting band around the pallet. NB: Can only be used with the
packaging on.
Remember that the product has a high centre of mass and should be
handled carefully.
The product must be transported and stored upright.
4.2 Positioning
• Remove the packaging and check before installation that the product
has not been damaged in transit. Report any transport damage to the
carrier.
• Place the product on a solid foundation, preferably made of concrete.
If the product needs to be placed on a soft carpet, base plates
must be placed under the adjustable feet.
• Avoid placing the heat pump in rooms where the walls are of lightweight
design, as people in the adjoining room may be disturbed by the
compressor and vibrations.
• Remember to leave a service area of at least 1 metre in front of the
product.
• The product must not be placed below floor level either.
4.3 Recycling
• The packaging must be deposited at a recycling station or with the
installation engineer for correct waste management.
• Obsolete products must be disposed of correctly and transported to a
waste station or distributor/retailer offering this service.
It is very important that the product’s refrigerant is disposed of
correctly.
Disposal of the product as household waste is not permitted.
• It is very important that the product’s refrigerant, compressor oil and
electric/electronic components are disposed of correctly.
4.4 After commissioning
• The installation engineer advises the property owner on the construction
and servicing of the system.
• The installation engineer fills in a checklist and contact information – the
customer and installation engineer sign the list, which the customer
keeps.