Giacomini GE556-4 Series Operating instructions

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ge556-4 series
GE556Y320 - GE556Y321
(High temperature)
GE556Y322 - GE556Y323
(Low temperature)
Index
1. General information ....................................................................................................................................................... 1
1.1 Warnings ........................................................................................................................................................1
1.2 Versions and product codes............................................................................................................................. 1
1.3 Completion codes ......................................................................................................................................... 2
1.4 Main characteristics ....................................................................................................................................... 2
1.5 Technical data ................................................................................................................................................ 2
1.6 Dimensions ....................................................................................................................................................3
2. Operation ....................................................................................................................................................................... 4
2.1 GE556Y320-GE556Y321 operation .................................................................................................................4
2.1.1 GE556Y320-GE556Y321 operational data .....................................................................................6
2.1.2 GE556Y320-GE556Y321 energy saving characteristics .................................................................. 8
2.2 GE556Y322-GE556Y323 operation ..................................................................................................................10
2.2.1 GE556Y322-GE556Y323 operational data ......................................................................................12
2.2.2 GE556Y322-GE556Y323 energy saving characteristics ................................................................. 14
3. Components .................................................................................................................................................................. 16
4. Installation.........................................................................................................................................................................17
4.1 Unpacking ..................................................................................................................................................... 17
4.2 Installation set-up ............................................................................................................................................ 17
4.3 Hydraulic system precautions ........................................................................................................................ 17
4.4 Electric system precautions.............................................................................................................................. 17
4.5 Template and HIU installation .................................................................................................................... 17
4.6 Start-up ............................................................................................................................................................19
4.6.1 GE556Y320-GE556Y321 start-up ................................................................................................... 19
4.6.2 GE556Y322-GE556Y323 start-up ................................................................................................... 20

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4.7 Flow and energy meter installation.................................................................................................................. 21
4.8 HIU electric connections ........................................................................................................................... 21
4.9 Thermostat electric connections ..................................................................................................................... 21
4.9.1 General warnings ........................................................................................................................... 21
4.9.2 Positioning of thermostat ..............................................................................................................21
4.10 Electric diagrams ...........................................................................................................................................22
4.10.1 GE556Y320-GE556Y321 HIU electric diagrams ...................................................................... 22
4.10.2 GE556Y322-GE556Y323 HIU electric diagrams ...................................................................... 23
5. HIU setting ................................................................................................................................................................. 24
5.1 Setting of dierential pressure control valve ....................................................................................................24
5.2 Setting of primary by-pass ...............................................................................................................................26
5.3 GE556Y320-GE556Y321: setting of static balancing valve ............................................................................... 26
5.4 GE556Y322-GE556Y323: setting of thermostatic head and circulator ............................................................. 27
6. Troubleshooting ............................................................................................................................................................... 28
6.1 DHW temperature too low ...............................................................................................................................
28
6.2 DHW temperature too high .............................................................................................................................28
6.3 Heating circuit water temperature too low ..................................................................................................... 28
6.3.1 GE556Y320-GE556Y321 ................................................................................................................28
6.3.2 GE556Y322-GE556Y323 ................................................................................................................29
6.4 Heating circuit water temperature too high ....................................................................................................30
6.4.1 GE556Y320-GE556Y321 ................................................................................................................30
6.4.2 GE556Y322-GE556Y323 ................................................................................................................30
6.5 Heating circuit not working .............................................................................................................................30
6.5.1 GE556Y320-GE556Y321 ................................................................................................................30
6.5.2 GE556Y322-GE556Y323 ................................................................................................................30
6.6 Noise in the heating system ............................................................................................................................ 31
7. Inspections and service ....................................................................................................................................................32
8. Spare parts ...................................................................................................................................................................... 32
8.1 GE556Y320-GE556Y321 HIU spare parts ................................................................................................... 32
8.2 GE556Y322-GE556Y323 HIU spare parts .................................................................................................... 33
8.3 GE551Y075 template spare parts ....................................................................................................................34
9. Compliance statements ...................................................................................................................................................35

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1. General information
GE556Y320, 321, 322 and 323 HIUs enable metering thermal energy consumptions when heating and the production of Domestic
Hot Water (DHW) in modern autonomous systems with heat centralized production (eg. teleheating).
HIUs are controlled thermostatically by means of a 3-way priority valve.
Thermostatic control provides for the lowest return temperature when producing hot water.
1.1 Warnings
• Installation must be carried out by qualied personnel authorized by the building administration body. Comply with the regulations
in terms of use (installation, tting, etc...), operation, re-gauging and replacement of metering units. Also refer to assembly instructions
included with every metering unit.
• Risk of scalds and electric shocks. Only qualied personnel authorized by the building administration body should access the HIU.
Misuse may cause serious injuries to people and damage the system.
• An excessive temperature of the Domestic Hot Water may cause scalds to people; too cold water may lead to undesired bacterial
growth within the hot water system.
• Some HIU parts may overheat, do not touch them.
• Before connecting the HIU to the power line, make sure it has been properly lled with water. Starting the HIU without water inside
may damage the circulator and the HIU.
• When starting up the HIU, make sure no one uses the system water till the water temperature has been adjusted in order to prevent
scalds.
• To prevent polluting agents from entering the system, rst open the primary circuit valves and then the return valves when starting
up the HIU. Open the valves slowly to prevent pressure peaks.
• Do not cut o the electric power from the control panel. This may damage the circulator, the valve actuators, etc...
• The cleaning frequency of the sanitary water exchanger strongly depends on the hardness of the supply Domestic Cold Water.
• With water hardness values higher than 15°f we recommend using anti-scaling devices to be selected based on water characteristics.
• To enhance the resistance to limestone crusting, we recommend adjusting the sanitary water temperature at a value very close to
the value of actual use.
• When installing the HIU to control a low temperature zone, include a low-temperature safety thermostat on the controlled zone.
• Clean the sanitary water exchanger at the end of the rst year; then, based on the limestone crusting status, this period can be
extended to two years.
• The HIU can be used in closed boiler rooms for operation with non-aggressive uids (water, glycol-based water in compliance with
VDI 2035/ÖNORM 5195).
• The electrical installation must be done by qualied personnel, respecting the current legislation and Standards.
1.2 Versions and product codes
Product code Type Number of
exchanger plates Heating side power DHW exchanger nominal power
Template with
valves
GE556Y320 High temperature heating and
DHW production
30 plates 21 kW 56 kW
GE551Y075
GE556Y321 40 plates 67 kW
GE556Y322 Low temperature heating and
DHW production
30 plates 10 kW 56 kW
GE556Y323 40 plates 67 kW
Warning.
• Every HIU includes:
- a label with the HIU model identication data;
- a label proving its compliance with electric and hydraulic tests;
• Every HIU is identied by a serial number both inside and on the packaging.

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1.3 Completion codes
The components listed below may be installed on every HIU:
• Thermal energy meter series GE552
• Domestic Hot Water meter series GE552-2
• Template with 7 interception valves and 3/4”connections: code GE551Y075
1.4 Main characteristics
• Thermostatic regulation to control Domestic Hot Water temperature and heating temperature.
• AISI 316L stainless steel 30 or 40 plates heat exchanger, insulated.
• Flow switch for DHW production priority.
• Motorized 3-way priority valve.
• Automatic air vent valve with hygroscopic plug, pressure gauge and lter on primary side.
• By-pass on primary side to keep the heat exchanger warm.
• Dierential pressure control valve on primary side.
• Brass spacers to install energy and ow meters.
• Varnished metal sheet cabinet (RAL9010) with key lock.
• Safety valve with actuator on heating side.
GE556Y320-321 peculiarity
• Static balancing valve on heating circuit.
GE556Y322-323 peculiarity
• 15/6 - 130 mm electronic circulator.
• Safety pressure switch for low pressures.
• Thermostatic control of heating delivery temperature (23÷67 °C)
1.5 Technical data
• Max. operation temperature: 90 °C
• Max. operation pressure: 10 bar
Warning.
Max. operation dierential pressure for primary side = 2 bar (dierential pressure control valve)
• DHW secondary circuit temperature range: 20÷70 °C (SET POINT 50°C)
• Primary nominal ow: 1130 l/h @ 70 °C for 56 kW (GE556Y320, GE556Y321)
1280 l/h @ 70 °C for 67 kW (GE556Y322, GE556Y323)
• Power: 230 V; 50-60 Hz
• Weight: GE556Y320 ~22 kg
GE556Y321 ~23 kg
GE556Y322 ~25 kg
GE556Y323 ~26,5 kg

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1.6 Dimensions
GE551Y075 templates
450
390
ED
BCAFG
1524923 140
292
45 4560 60 60 60 60 60
95
Legend
X: Cable cover
A: Domestic Cold Water inlet
B: Domestic Cold Water outlet
C: Domestic Hot Water outlet
D: Primary inlet
E: Primary outlet
F: Heating delivery circuit
G: Heating return circuit
Dimensions mm
GE556Y320-321 HIUs
450
60 4545 6060606060
630
180
47
ABCEDFG
GE556Y322-323 HIUs
450
60 4545 6060606060
630
180
47
ABCEDFG
X

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2. Operation
2.1 GE556Y320-GE556Y321 operation
P
P
E
DFG
C
B
F
E
H
A
C
A
Legend
Heat exchanger Motorized 3-way priority valve Dierential pressure control
valve (DPC)
CCBrass spacer for DCW ow
meter
P
Dierential pressure probe-holder
A
Thermostatic head for
temperature control of
sanitary side
HHBrass spacer for DHW ow meter Filter Air vent automatic valve
Thermostatic head probe Housing for thermal energy
meter temperature probe Motorized 2-way zone valve
FFFlow switch Primary by-pass Static balancing valve
Pressure gauge EEBrass spacer for thermal energy
meter
A: Domestic Cold Water inlet
B: Domestic Cold Water outlet
C: Domestic Hot Water outlet
D: Primary inlet
E: Primary outlet
F: Heating delivery circuit
G: Heating return circuit

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Primary circuit
E
D
Fig. 1
Inlet (D) and return (E).The primary circuit includes a by-pass, an inspectionable lter, a dierential
pressure probe-holder, a motorized 3-way priority valve, an automatic air vent valve, a heat
exchanger, a pressure gauge, a minimum pressure switch, a thermostatic head to control the
sanitary water temperature and a dierential pressure control valve (DPC).
The thermal energy meter can be installed in place of the brass spacer by inserting its temperature
probe in the corresponding housing (Paragraph “3 Components - Housing for thermal energy
unit temperature probe”).
Heating circuit
E
DG
F
Fig. 2
Delivery (F) and return (G). The heating circuit includes a motorized 2-way zone valve working as
thermal and electric safety device and a static balancing valve.
Domestic Hot Water
Domestic Cold Water inlet (A), Domestic Cold Water outlet (B) and Domestic Hot Water outlet (C).
The DHW circuit includes a ow switch, a heat exchanger and brass spacers to install the DHW
and DCW ow meters.
BC
A
Fig. 3

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2.1.1 GE556Y320-GE556Y321 operational data
Note.
Operational data valid for dierential pressure of the control valve set at 50 kPa.
Primary circuit
Primary circuit for DHW production (see g.1)
Kv = 1,68 Kv = 1,83
10000
1000
ΔP [mm H2o]
Q [l/h]
100
10
10 100 100001000
GE556Y320
GE556Y321
Heating primary circuit - Dynamic balancing valve fully open (see g.2)
Kv = 1,64
10000
1000
ΔP [mm H2o]
Q [l/h]
100
10
10 100 100001000
Primary circuit by-pass
Kv = 0,20
10000
1000
ΔP [mm H2o]
Q [l/h]
100
10
10 100 100001000
Primary circuit by-pass
Heating
Nominal ow rate high temperature heating circuit:
540 l/h @ ΔT 15 °C (65-50 °C) for 9,5 kW
1200 l/h @ ΔT 15 °C (65-50 °C) for 21 kW
410 l/h @ ΔT 20 °C (70-50 °C) for 9,5 kW
910 l/h @ ΔT 20 °C (70-50 °C) for 21 kW

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DCW production
Domestic Cold Water circuit (DCW)
Kv = 6,20
10000
1000
ΔP [mm H2o]
Q [l/h]
100
10
10 100 100001000
DHW production
Domestic hot water GE556Y321
(Δt 10-50 °C) Primary circuit working conditions
Flow rate
[l/min]
Flow rate
[l/h]
Power
[kW]
Inlet T
[° C]
Flow rate
[l/h]
Outlet T
[° C]
12 720 33,5 70 580 20
65 670 22
15 900 42 70 750 22
65 880 24
17 1020 47,5 70 880 23,5
65 1020 25
20 1200 56 70 1050 24,2
65 1230 26
22 1320 61,5 70 1160 24,6
24 1440 67 70 1280 25
Domestic hot water GE556Y320
(Δt 10-50 °C) Primary circuit working conditions
Flow rate
[l/min]
Flow rate
[l/h]
Power
[kW]
Inlet T
[° C]
Flow rate
[l/h]
Outlet T
[° C]
12 720 33,6 70 620 23
65 730 25
15 900 42 70 800 24
65 940 26
17 1020 47,6 70 940 26
65 1090 27
20 1200 56 70 1130 27
Domestic Hot Water circuit (DHW)
10000
1000
ΔP [mm H2o]
Q [l/h]
100
10
10 100 100001000
GE556Y320
GE556Y321
Kv = 1,70 Kv = 1,80
Note.
For regulation of static balancing valves and dierential pressure control valves (Paragraph“5 HIU setting”).

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2.1.2 GE556Y320-GE556Y321 energy saving characteristics
Hot water primary circuit ow based on DHW ow at 45 °C
30 plate model
Primary ow [l/h]
Hot water primary circuit ow based on DHW ow at 50 °C
30 plates model
Primary ow [l/h]
Hot water primary circuit ow based on DHW ow at 55 °C
30 plates model
Primary ow [l/h]

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Hot water primary circuit ow based on DHW ow at 45 °C
40 plate model
Primary ow [l/h]
Hot water primary circuit ow based on DHW ow at 50 °C
40 plate model
Primary ow [l/h]
Hot water primary circuit ow based on DHW ow at 55 °C
40 plate model
Primary ow [l/h]

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2.2 GE556Y322-GE556Y323 operation
P
P
E
DFG
C
B
F
P
E
H
A
C
B
A B
Legend
Heat exchanger Motorized 3-way priority valve Dierential pressure control
valve (DPC)
CCBrass spacer for DCW ow
meter
P
Dierential pressure probe-holder
A
Thermostatic head for sanitary
side temperature control
HHBrass spacer for DHW ow meter Filter Automatic air vent valve
Thermostatic head probe Housing for thermal energy
meter temperature probe Motorized 2-way zone valve
FFFlow switch Primary by-pass BR462L thermostatic head
Pressure gauge EEBrass spacer for thermal energy
meter BHeating lockshield valve
PP
Minimum pressure switch Circulator
A: Domestic Cold Water inlet
B: Domestic Cold Water outlet
C: Domestic Hot Water outlet
D: Primary inlet
E: Primary outlet
F: Heating delivery
G: Heating return

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Primary circuit
E
D
Fig. 1
Inlet (D) and return (E).The primary circuit includes a by-pass, an inspectionable lter, a dierential
pressure probe-holder, a motorized 3-way priority valve, an automatic air vent valve, a heat
exchanger, a pressure gauge, a minimum pressure switch, a thermostatic head to control the
sanitary water temperature and a dierential pressure control valve (DPC).
The thermal energy metering unit can be installed in place of the brass spacer by inserting its
temperature probe in the corresponding housing (Paragraph “3 Components - Housing for
thermal energy meter temperature probe”).
Heating circuit
E
DG
F
Fig. 2
Delivery (F) and return (G). The heating circuit includes a self-modulating circulator, a by-pass
lockshield valve and a R462L thermostatic head to control the heating temperature.
Domestic Hot Water circuit
Domestic Cold Water inlet (A), Domestic Cold Water outlet (B) and Domestic Hot Water outlet (C). The
DHW circuit includes a ow switch, a heat exchanger and brass spacers to insert the DHW and
DCW ow meters.
BC
A
Fig. 3

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2.2.1 GE556Y322-GE556Y323 operational data
Note.
Operational data valid when setting the dierential pressure control valve at 50 kPa.
Primary circuit
Primary circuit for DHW production (see g.1)
Kv = 1,68 Kv = 1,83
10000
1000
ΔP [mm H2o]
Q [l/h]
100
10
10 100 100001000
GE556Y322
GE556Y323
Primary circuit for heating (see g.2)
Kv = 1,33
10000
1000
ΔP [mm H2o]
Q [l/h]
100
10
10 100 100001000
Primary circuit by-pass
Kv = 0,20
10000
1000
ΔP [mm H2o]
Q [l/h]
100
10
10 100 100001000
Primary circuit by-pass
Heating
Heating GE556Y322/323
(Δt 45-39 °C) Primary circuit working conditions
Circulator
speed
Flow rate
[l/h]
Power
[kW]
Inlet T
[° C]
Flow rate
[l/h]
Outlet T
[° C]
Max. 1200 10 70 280 39
65 340 39
Heating GE556Y322/323
(Δt 35-30 °C) Primary circuit working conditions
Circulator
speed
Flow rate
[l/h]
Power
[kW]
Inlet T
[° C]
Flow rate
[l/h]
Outlet T
[° C]
Max. 1500 8,8 70 190 30
65 215 30
00 200 400 600 800 1000 1200 1400 1600
1
2
3
4
5
6
7
∆p [m H
2
O]
Q [l/h]
Circuit loss of pressure curve

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DCW production
Domestic Cold Water circuit (DCW)
Kv = 6,20
10000
1000
ΔP [mm H2o]
Q [l/h]
100
10
10 100 100001000
DHW production
Domestic hot water GE556Y321
(Δt 10-50 °C) Primary circuit working conditions
Flow rate
[l/min]
Flow rate
[l/h]
Power
[kW]
Inlet T
[° C]
Flow rate
[l/h]
Outlet T
[° C]
12 720 33,5 70 580 20
65 670 22
15 900 42 70 750 22
65 880 24
17 1020 47,5 70 880 23,5
65 1020 25
20 1200 56 70 1050 24,2
65 1230 26
22 1320 61,5 70 1160 24,6
24 1440 67 70 1280 25
Domestic hot water GE556Y320
(Δt 10-50 °C) Primary circuit working conditions
Flow rate
[l/min]
Flow rate
[l/h]
Power
[kW]
Inlet T
[° C]
Flow rate
[l/h]
Outlet T
[° C]
12 720 33,6 70 620 23
65 730 25
15 900 42 70 800 24
65 940 26
17 1020 47,6 70 940 26
65 1090 27
20 1200 56 70 1130 27
Domestic Hot Water circuit (DHW)
10000
1000
ΔP [mm H2o]
Q [l/h]
100
10
10 100 100001000
GE556Y320
GE556Y321
Kv = 1,70 Kv = 1,80
Note.
For regulation of static balancing valves and dierential pressure control valves (Paragraph“5 HIU setting”).

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2.2.2 GE556Y322-GE556Y323 energy saving characteristics
Hot water primary circuit ow rate based on DHW ow at 45 °C
30 plate model
Primary ow [l/h]
Hot water primary circuit ow rate based on DHW ow at 50 °C
30 plate model
Primary ow [l/h]
Hot water primary circuit ow rate based on DHW ow at 55 °C
30 plate model
Primary ow [l/h]

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Hot water primary circuit ow rate based on DHW ow at 45 °C
40 plate model
Primary ow [l/h]
Hot water primary circuit ow rate based on DHW ow at 50 °C
40 plate model
Primary ow [l/h]
Hot water primary circuit ow rate based on DHW ow at 55 °C
40 plate model
Primary ow [l/h]

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3. Components
ED
BCA
1
3
15
13
16
17
5
7
14
8
9
4
10
11
2
12
18
19
6
FG
20
Legend
1Housing for thermal en. met. unit temp. probe
PRIMARY
2Filter
3Dierential pressure probe-holder
4Probe for dierential pressure control valve
5Motorized 3-way priority valve for DHW function
6Pressure gauge
7Heat exchanger, DHW function
8Thermostatic head for sanitary side temperature
control
9Automatic air vent valve
10 Dierential pressure probe holder
11 Dierential pressure control valve (DPC)
12 Brass spacer for thermal energy meter
13 Primary circuit by-pass
14 Flow switch
DHW PRO-
DUCTION
15 Thermostatic head probe
16 Brass spacer for DHW meter
17 Brass spacer for DCW meter
18 Motorized 2-way zone valve HEATING
19 Static balancing valve
20 Electric cabinet CONTROLS
A: DCW inlet
B: DCW outlet
C: DHW outlet
D: Primary inlet
E: Primary outlet
F: Heating delivery
G:Heating return
GE556Y320-GE556Y321
ED
BCA
1
3
17
18
5
7
15
8
23
9
4
21
22
10
11
12
13
19
20
6
FG
16
14
2
Legend
1Housing for thermal en. met. unit temp. probe
PRIMARY
2Filter
3Dierential pressure probe-holder
4Probe for dierential pressure control valve
5Motorized 3-way priority valve for DHW function
6Pressure gauge
7Heat exchanger, DHW function
8Thermostatic head for sanitary side temperature
control
9Automatic air vent valve
10 Minimum pressure switch
11 Dierential pressure probe-holder
12 Dierential pressure control valve (DPC)
13 Brass spacer for thermal energy meter
14 Primary circuit by-pass
15 Flow switch
DHW PRO-
DUCTION
16 Thermostatic head probe
17 Brass spacer for DHW meter
18 Brass spacer for DCW meter
19 Circulator
HEATING
20 Heating circuit lockshield valve
21 Motorized 2-way zone valve
22 R462L thermostatic head for heating temp. control
23 Electric cabinet CONTROLS
A: DCW inlet
B: DCW outlet
C: DHW outlet
D: Primary inlet
E: Primary outlet
F: Heating delivery
G:Heating return
GE556Y322-GE556Y323

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4. Installation
4.1 Unpacking
• Remove the shipping packing, make sure the product is not damaged and that delivery has been carried out according to the
agreed terms and conditions.
• When handling the HIU, the pipes and the exchanger should not be exposed to stress. Do not move the HIU holding it by the
exchanger or pipes
4.2 Installation set up
• Make sure the primary circuit complies with the rules in force. The available dierential pressure must be included between a
minimum of 0,5 bar and a maximum of 2 bar. In case of higher pressure values, install a dierential pressure controller.
• Wash the heating and Domestic Hot Water circuit.
4.3 Hydraulic system precautions
• Max. working temperature: 90 °C
• Primary circuit max. working pressure: 10 bar
• DHW secondary circuit max. working pressure: 10 bar
Warning.
Max. working dierential pressure for primary side = 2 bar
4.4 Electric system precautions
• Make sure the power voltage is 230 V and that the entire HIU is properly connected to the grounding network.
We recommend installing a 10 A magnetothermic dierential switch to protect the HIU.
4.5 Template and HIU installation
Warning.
Hydraulic connection of heating, sanitary water and primary circuits should be carried out by qualied personnel and in
compliance with the local or national rules and provisions in force.
We recommend installing a check valve on the sanitary water circuit inlet.
The HIU can be installed at any height however we recommend a distance of 1500÷1800 mm from the floor to the bottom edge
of the HIU cover.
Before installing the template and the HIU on the wall, make 4 holes to t them (A, C).
The holes must be suitable to t the screw anchors properly.
390 mm
415 mm
525 mm
C C C C
A
B B B B
AA A A A
1500÷1800 mm
GE551Y075
GE556Y320-1-2-3

18
0850EN May 2020
User and maintenance manUal
HigH or low temperature HiuswitH tHermostatic
control ge556Y320-321-322-323
ge556-4 series
CC
A
B
A
B
Install the GE551Y075 template on the wall using screw anchors t for the type of
wall and equipment weight (A).
Install the ball valves in the corresponding template holes and tighten them with a
wrench using the locknut.
Connect the system pipes to the ball valves with the 3/4’’M template connections
using proper adapters. For proper installation of the pipes, refer to the indications on
the template label.
Warning.
Before installing the HIU, wash the system primary and secondary circuits.
Warning.
Before connecting the template to the HIU, remove the lock nuts from the threaded connections.
A
A
B
BB
B
A
A
C
C
CC
Install the GE556Y320-321-322-323 HIU in the
corresponding threaded pegs on the template (B) and
lock it using the washers and nuts included with the
template.
The HIU top must be locked to the wall using the
holes (C) previously drilled and the screw anchors
suitable for the type of wall and equipment weight.
Before connecting the HIU to the template, t the gaskets between
the HIU connections and the template valve caps.
MAX. 35 Nm
Tighten the template valve caps using a 35 Nm max. torque.