
G-2 A-070336_EN • Rev. A
Table of ConTenTs
General InformatIon ................................G-4
Liabilities of the Manufacturer, the Installer
and the End user ..............................................G-4
About this Manual ............................................G-5
Safety Instructions ...........................................G-6
Package Contents ...........................................G-7
Boiler Marking ..................................................G-7
Product descrIPtIon ...............................G-8
Nesta 120 - 160 - 200 - 250.............................G-8
General Description .................................................G-8
Frost Protection .......................................................G-8
Safety Devices .........................................................G-8
Optional equipment .................................................G-8
Control Panel and Main Functions.................G-10
Symbols and Messages on the Control Panel ...G-11
technIcal sPecIfIcatIons ........................G-12
Dimensions and Clearances...........................G-12
Performance and Eciency Data...................G-14
ERP Data........................................................G-14
Electrical Data ................................................G-14
Combustion and Gas Data.............................G-15
Hydraulic Data................................................G-16
Pressure Drop Curve ......................................G-16
Flow Rate .......................................................G-16
InstructIons for the user......................u-17
Safety Instructions for the User......................U-17
Periodic checks .............................................U-18
Starting the Appliance....................................U-19
Stopping the Appliance..................................U-19
What to Do if... ...............................................U-19
Basic Settings ................................................U-20
Structure of Menus for the End User .............U-23
Product InstallatIon .............................. I-25
Safety Instructions for the Installation............. I-25
Handling the Product ...................................... I-26
Unpacking the Product ................................... I-26
Installing and Preparing the Boiler .................. I-26
Removing and Installing the Access Panels ... I-27
Requirements for the Hydraulic Connections . I-28
Water Quality Requirements to Prevent
Scaling and Corrosion..................................... I-29
Typical Hydraulic Connections - Heating Circuit.. I-30
Hydraulic Connections - Cascaded boilers,
with External Domestic Hot Water Tank and
Plate Heat Exchanger...................................... I-31
Hydraulic Connections - Cascaded boilers,
with External Domestic Hot Water Tank and
Low Loss Header ............................................ I-32
Safety Instructions for the Gas Connection .... I-33
Safety Instructions for the Chimney Connections I-34
Chimney Connection....................................... I-36
Accessories ..................................................... I-36
Engineering the Chimney System ................... I-37
Safety Instructions for the Electrical
Connections .................................................... I-38
Connections .................................................... I-38
Accessing the High Voltage Terminal Strip ..... I-38
Accessing the Low Voltage Terminal
Strip and Electronic board............................... I-39
Routing the Cables.......................................... I-39
Wiring Diagram................................................ I-40
commIssIonInG ........................................ I-42
Safety Instructions Before Start-up................. I-42
Filling the System ............................................ I-42
Start-up and Combustion Adjustments .......... I-43
maIntenance........................................... I-44
Safety Instructions for Maintenance ............... I-44
Maintenance Requirements ............................ I-45
Shutting Down for Maintenance...................... I-46
Draining the Boiler........................................... I-46
Restarting after Maintenance .......................... I-46
Cleaning the Condensate Pipe and Trap......... I-47
Removing and Installing the Fan and Air
Adapter Assembly ........................................... I-48
Removing and Installing the Ignition and
Ionization Electrodes ....................................... I-50
Removing and Installing the Burner ................ I-51
Checking and Cleaning the Combustion
Chamber.......................................................... I-52
addItIonal InformatIon for the Installer.. I-53
Optional Modules ............................................ I-53
Additional Heating Circuit Modules & Cable Hub......I-53
Web Server Module .................................................I-53
Cascading module...................................................I-53
Boilers in a Cascade System .......................... I-54
Boiler Settings for the Installer ........................ I-56
Access Levels..........................................................I-56
Commissioning Menu ..............................................I-56
Menus and Settings .................................................I-56
Structure of Menus for the Installer................. I-56
Error Codes and Solutions .............................. I-60
Troubleshooting............................................... I-64
Maintenance Messages .................................. I-65
Installation Checklist ....................................... I-66
Combustion Parameters - Log Sheet.............. I-69
Water Parameters - Log Sheet........................ I-70
declaratIon of conformIty ..................... I-71