Pentair FLECK 3900 NXT User guide

FLECK
3900 NXT
INSTALLER
MANUAL
WATER PURIFICATION

Installer Manual Fleck 3900 - NXT - Table of contents
2 / 126 Ref. MKT-IM-015 / B - 08.06.2018
Table of contents
1. Generalities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.1. Scope of the documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
1.2. Release management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.3. Manufacturer identifier, product . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.4. Intended use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.5. Abbreviations used . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1.6. Norms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1.6.1. Applicable norms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1.6.2. Available certificates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1.7. Procedure for technical support . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
1.8. Copyright . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
1.9. Limitation of liability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
1.10. Scan & Service application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2. Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
2.1. Safety pictograms definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
2.2. Serial label location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
2.3. Hazards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
2.3.1. Personnel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
2.3.2. Material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
2.4. Hygiene and sanitization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
2.4.1. Sanitary issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
2.4.2. Hygiene measures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
3. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
3.1. Technical specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
3.1.1. Performance flow rate characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . 16
3.2. Outline drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
3.3. Components description and location . . . . . . . . . . . . . . . . . . . . . . . 17
3.4. System regeneration cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
3.4.1. DF regeneration cycle (5-cycles operation). . . . . . . . . . . . . . . . . . . . . . 18
3.4.2. UF regeneration cycle (5-cycles operation). . . . . . . . . . . . . . . . . . . . . . 20
3.4.3. Filter cycle (3-cycles operation) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
3.5. Injector block position for DF and UF configurations . . . . . . . . . . . 24

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4. System sizing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
4.1. Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
4.1.1. Injector/DLFC/BLFC-Valve configuration . . . . . . . . . . . . . . . . . . . . . . . 25
4.2. Sizing a softener (single unit) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
4.2.1. Parameters to be considered. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
4.2.2. Determining the required volume of resin . . . . . . . . . . . . . . . . . . . . . . 27
4.2.3. Resin exchange capacity and capacity of the unit . . . . . . . . . . . . . . . . 28
4.2.4. Valve configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
4.2.5. Cycle time calculation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
4.3. Defining salt quantities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
4.4. 1800 Injector flow rates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
5. Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
5.1. Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
5.2. Safety notices for installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
5.3. Installation environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
5.3.1. General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
5.3.2. Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
5.3.3. Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
5.3.4. Mechanical. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
5.4. Integration constraints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
5.5. Valve connection to piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
5.5.1. Top-mounted valve installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
5.5.2. Side-mounted valve installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
5.6. Block diagram and configuration example . . . . . . . . . . . . . . . . . . 43
5.7. System types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
5.7.1. Single valve (System #4). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
5.7.2. Multiple valves with lockout (System #5) . . . . . . . . . . . . . . . . . . . . . . . 45
5.7.3. Multiple valves with consecutive regenerations (System #6) . . . . . . . 46
5.7.4. Duplex alternating (System #7) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
5.7.5. Multiple valves, alternating (System #9). . . . . . . . . . . . . . . . . . . . . . . . 47
5.7.6. Multiple valves, demand (System #14) . . . . . . . . . . . . . . . . . . . . . . . . . 47
5.8. Valve connection to piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
5.9. Electrical connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
5.9.1. Connections for multiple valves. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
5.10. Bypassing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
5.11. Drain line connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
5.12. Overflow line connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
5.13. Brine line connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

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6. Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
6.1. Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
6.1.1. During service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
6.2. Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
6.3. Setting the time of the day . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
6.4. Basic programming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
6.4.1. Language setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
6.4.2. Inlet water hardness. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
6.4.3. Regeneration days override . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
6.4.4. Regeneration start time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
6.5. Master programming mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
6.5.1. Master programming mode chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
6.5.2. Entering master programming mode . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
6.5.3. Language setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
6.5.4. System type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
6.5.5. Valve address in the system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
6.5.6. System size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
6.5.7. Regeneration type. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
6.5.8. Valve type. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
6.5.9. Regeneration flow. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
6.5.10. Remote started regeneration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
6.5.11. Display format. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
6.5.12. System capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
6.5.13. Safety coefficient. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
6.5.14. Inlet water hardness. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
6.5.15. Trip points setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
6.5.16. Regeneration days override . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
6.5.17. Regeneration start time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
6.5.18. Programming regeneration cycle times. . . . . . . . . . . . . . . . . . . . . . . . . 71
6.5.19. Auxiliary relay/Chemical pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
6.5.20. Flow meter selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
6.5.21. Parameters saving . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
6.6. Diagnostic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
6.6.1. Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
6.6.2. Current flow rate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
6.6.3. Peak flow rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
6.6.4. Totalizer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
6.6.5. Hours between last two regenerations. . . . . . . . . . . . . . . . . . . . . . . . . . 75
6.6.6. Hours since last regeneration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
6.6.7. Volume remaining. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
6.6.8. Valve position . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
6.6.9. Software version . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
6.7. Resetting the controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
6.7.1. Partial reset. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
6.7.2. Hard reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

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7. Commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78
7.1. Water filling, draining and waterproofness inspection . . . . . . . . . 78
7.1.1. Activating a single valve system (System #4) . . . . . . . . . . . . . . . . . . . . 78
7.1.2. Activating a multiple valves system (Systems #5, #6, #7, #9 and 
#14) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
7.2. Sanitization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
7.2.1. Disinfection of water softeners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
7.2.2. Sodium or calcium hypochlorite . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
7.2.3. Electro chlorination. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
8. Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .81
8.1. Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
8.1.1. During service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
8.1.2. During regeneration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
8.1.3. LED status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
8.2. Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
8.3. Manual regeneration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
8.3.1. Manual delayed regeneration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
8.3.2. Immediate regeneration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
8.4. To advance regeneration cycles . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
8.5. Operation during a power failure . . . . . . . . . . . . . . . . . . . . . . . . . . 82
9. Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .83
9.1. Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
9.1.1. Use original spare parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
9.1.2. Use original approved lubricants. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
9.1.3. Maintenance instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
9.2. Cleaning and maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
9.2.1. First steps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
9.2.2. Replacing the upper/lower power head motor. . . . . . . . . . . . . . . . . . . 84
9.2.3. Replacing micro-switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
9.2.4. Replacing the upper piston and/or seal and spacer kit . . . . . . . . . . . . 86
9.2.5. Replacing the lower piston and/or seal and spacer kit . . . . . . . . . . . . 88
9.2.6. Replacing the upper/lower cam. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
9.2.7. Cleaning the injector. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
9.2.8. Cleaning the BLFC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
9.2.9. Cleaning the DLFC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
9.2.10. Valve on tank assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94

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10. Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
10.1. Error detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95
10.2. Programming error . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .97
10.3. Examples of error displayed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
11. Spare parts and options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
11.1. BLFC parts list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99
11.2. Valve parts list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .100
11.3. Upper power head parts list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .102
11.4. Lower power head parts list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .104
11.5. Injector parts list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
11.6. Top mounted valve distribution systems parts list . . . . . . . . . . . .108
11.6.1. Tanks 30" - 36" flanged 6", TM, slots 0.3 mm . . . . . . . . . . . . . . . . . . . 108
11.6.2. Tanks 42" - 48" flanged 6", TM, slots 0.3 mm . . . . . . . . . . . . . . . . . . . 109
11.7. Side mounted valve distribution systems parts list . . . . . . . . . . . 110
11.7.1. Tanks 42" - 63" flanged 6", SM, top distribution, DN80 
connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
11.7.2. Tanks 42" - 63" flanged 6", SM, bottom distribution, DN80 
connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
11.7.3. Tanks 42" - 63" flanged 6", SM, top & bottom distribution, DN100
connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
11.8. Safety brine valves list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .116
11.9. Air checks list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .116
11.10. DLFC parts list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
11.11. Meters parts list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .118
11.12. Tank adapter, top mounted, threaded 6" list . . . . . . . . . . . . . . . .119
11.13. Tank adapter, TM, flanged 6" list . . . . . . . . . . . . . . . . . . . . . . . . . .120
11.14. SM adapter list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
11.15. Kit meter & Meter cables list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
11.16. Other components list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .123
11.17. CE compliance parts list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
12. Disposal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124

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1. Generalities
1.1. Scope of the documentation
The documentation provides the necessary information for appropriate use of the product. It informs
the user to ensure efficient execution of the installation, operation or maintenance procedures.
The content of this document is based on the information available at the time of publication. The
original version of the document was written in English.
For safety and environmental protection reasons, the safety instructions given in this documentation
must be strictly followed.
This manual is a reference and will not include every system installation situation. The person
installing this equipment should have:
• training in the Fleck series, NXT controllers and water softener installation;
• knowledge of water conditioning and how to determine proper controller settings;
• basic plumbing skills.
This document is available in other languages on https://www.pentairaquaeurope.com/product-
finder/product-type/control-valves.
1.2. Release management
1.3. Manufacturer identifier, product
Manufacturer: Pentair International LLC
Avenue de Sevelin 18
1004 Lausanne
Switzerland
Product: Fleck 3900 - NXT
1.4. Intended use
The device is intended for industry environment use only and it is purpose-built for water treatment.
Revision Date Author Description
A21.11.2017 BRY/PBO First edition
B08.06.2018 BRY/FMI Address change, Bleam information and valve on
tank assembly.

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1.5. Abbreviations used
assy ......................................................... Assembly
BLFC ....................................................... Brine Line Flow Controller
BV............................................................ Brine Valve
DF............................................................ Down Flow
DLFC ....................................................... Drain Line Flow Controller
HW........................................................... Hot Water
Inj ............................................................ Injector
NBP......................................................... No By Pass
PH ........................................................... Power Head
QC............................................................ Quick Connect
Regen...................................................... Regeneration
S&S ......................................................... Seals & Spacers
SBV.......................................................... Safety Brine Valve
SM ........................................................... Side Mounted
TC ............................................................ Time Clock
TM ........................................................... Top Mounted
UF............................................................ Up Flow
1.6. Norms
1.6.1. Applicable norms
Comply with the following guidelines:
• 2006/42/EC: machinery directive;
• 2014/35/UE: low voltage directive;
• 2014/30/UE: electromagnetic compatibility;
• 2011/65/CE: restriction of use of certain hazardous substances in electrical and electronic
equipment (RoHS);
• UNI EN ISO9001 (certificate no. 95.022 SSG ICS).
Meets the following technical standards:
• EN 55014-1;
• EN 55014-2;
• EN 61000-6-1;
• EN 61000-6-2;
• EN 61000-6-3;
• EN 61000-6-4;
• EN 61010-1.
1.6.2. Available certificates
•CE;
•ACS;
•DM174.
Access to all certifications:

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1.7. Procedure for technical support
Procedure to follow for any technical support request:
ACollect the required information for a technical assistance request:
• product identification (see chapters 2.2. Serial label location, page 11 and 
9.1. Recommendations, page 83);
• description of the device problem.
BPlease refer to the chapter 10. Troubleshooting, page 95. If the problem persists contact your
supplier.
1.8. Copyright
© 2018 Pentair International Sàrl. All rights reserved.
1.9. Limitation of liability
Pentair Quality System EMEA products benefit, under specific conditions, from a manufacturer
warranty that may be invoked by Pentair’s direct customers. Users should contact the vendor of this
product for applicable conditions and in case of a potential warranty claim.
Any warranty provided by Pentair regarding the product will become invalid in case of:
• improper installation, improper programming, improper use, improper operation and/or
maintenance leading to any kind of product damages;
• improper or unauthorized intervention on the controller or components;
• incorrect, improper or wrong connection/assembly of systems or products with this product and
vice versa;
• use of a non-compatible lubricant, grease or chemicals of any type and not listed by the
manufacturer as compatible for the product;
• failure due to wrong configuration and/or sizing.
Pentair accepts no liability for equipment installed by the user upstream or downstream of Pentair
products, as well as for process/production processes which are installed and connected around or
even related to the installation. Disturbances, failures, direct or indirect damages that are caused by
such equipment or processes are also excluded from the warranty. Pentair shall not accept any
liability for any loss or damage to profits, revenues, use, production, or contracts, or for any indirect,
special or consequential loss or damage whatsoever. Please refer to the Pentair List Price for more
information about terms and conditions applicable to this product.

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1.10. Scan & Service application
Scan & Service mobile application is the ideal support for the maintenance person in his daily
business. A simple scan of an identification (ID) label (1) present on the valve with a smartphone gives
an instantaneously access to all updated information related to the product, such as:
• valve’s and tanks detailed configuration;
•manuals;
• spare parts lists;
• troubleshooting recommendations;
• multi-lingual videos, detailing how to best service a part;
• informations about new products, latest technologies, novelties about the Blue Network
program, etc....
No. Operation
ADownload the application "Scan & Service" from or in a
smartphone (4).
BOpen the application "Scan & Service".
CScan the bleam (3) stuck on the valve (2).
DNavigate to find information.

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2. Safety
2.1. Safety pictograms definition
2.2. Serial label location
Note
Ensure that the serial label and the safety labels on the device are completely legible and
clean. If necessary, replace them with new labels in the same positions.
Caution
Warns of a risk of minor injury or major
material damage to the device or
environment.
Warning
Warns against serious personal injury
and damage to health.
Danger
Warns against serious personal injury or
death.
Mandatory
Standard or measure to apply. 
Note
Comment.
Prohibition
Restriction to be observed.
Model
Electrical rating
Part number
Production date
Production order
Serial number

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2.3. Hazards
All the safety and protection instructions contained in this document must be observed in order to
avoid temporary or permanent injury, damage to property or environmental pollution.
At the same time, any other legal regulations, accident prevention and environmental protection
measures, as well as any recognized technical regulations relating to appropriate and risk-free
methods of working which apply in the country and place of use of the device must be adhered to.
Any non-observation of the safety and protection rules, as well as any existing legal and technical
regulations, will result in a risk of temporary or permanent injury, damage to property or
environmental pollution.
2.3.1. Personnel
Only qualified and professional personnel, based on their training, experience and instruction as well
as their knowledge of the regulations, safety rules and operations performed, are authorized to carry
out necessary work.
2.3.2. Material
The following points must be observed to ensure proper operation of the system and the safety of
user:
• be careful of high voltages present on the transformer (230V);
• do not put your fingers in the system (risk of injuries with moving parts and shock due to electric
voltage).
2.4. Hygiene and sanitization
2.4.1. Sanitary issues
Preliminary checks and storage
• Check the integrity of the packaging. Check that there is no damage and no signs of contact with
liquid to make sure that no external contamination occurred;
• the packaging has a protective function and must be removed just before installation. For
transportation and storage, appropriate measures should be adopted to prevent the
contamination of materials or the objects themselves.

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Assembly
• Assemble only with components which are in accordance with drinking water standards;
• after installation and before use, perform one or more manual regenerations in order to clean
the media bed. During such operations, do not use the water for human consumption. Perform a
disinfection of the system in the case of installations for treatment of drinking water for human
use.
Note
This operation must be repeated in the case of ordinary and extraordinary maintenance. It
should also be repeated whenever the system remains idle for a significant time.
Note
Valid only for Italy: In case of equipment used in accordance with the DM25, apply all the
signs and obligations arising from the DM25.
2.4.2. Hygiene measures
Disinfection
• The materials used for the construction of our products meet the standards for use with potable
water; the manufacturing processes are also geared to preserving these criteria. However, the
process of production, distribution, assembly and installation, may create conditions of bacterial
proliferation, which may lead to odor problems and water contamination;
• it is therefore strongly recommended to sanitize the products. See 7.2. Sanitization, page 79;
• maximum cleanliness is recommended during the assembly and installation;
• for disinfection, use Sodium or Calcium Hypochlorite and perform a manual regeneration.

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3. Description
3.1. Technical specifications
Design specifications/ratings
Valve body ............................................... Brass
Rubber components ............................... EP or EPDM
Weight (valve with controller & meter) .. 41.0 kg (max)
Recommended operating pressure ....... 1.8 - 8.6 bar
Maximum inlet pressure ........................ 8.6 bar
Hydrostatic test pressure....................... 20 bar
Water temperature std........................... 1 - 43°C
Ambient temperature............................. 5 - 40°C
Regeneration flow .................................. DF or UF
Bypass of raw water during regeneration:
Standard ................................................. Yes
NBP version ............................................ No
Flow rates (3.5 bar inlet - valve only - top mount)
Continuous service flow (Δp = 1 bar)...... 57.0 m3/h
Peak service flow (Δp = 1.8 bar) ............. 74.0 m3/h
Cv*........................................................... 65.0
Kv*........................................................... 56.4
Maximum backwash flow (Δp = 1.8 bar). 24.0 m3/h
*Cv : Flow rate in gpm across the valve at a pressure drop of 1 psi at 60°F.
*Kv : Flow rate in m3/h across the valve at a pressure drop of 1 bar at 16°C.
Valve connections
Tank top mounted adapter ..................... 6" flanged or 6" thread
Side mount adapter ................................ 3" BSP female
Inlet/Outlet ............................................. 3" BSP female
Distributor pilot ...................................... 90 mm [DN90]
Drain line ................................................ 2" BSP
Brine line (1800)...................................... 1" NPT male

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Electrical
Controller operating voltage .................. 24 VAC
Input supply frequency ........................... 50/60 Hz
Transformer voltage............................... 24 VAC
Motor input voltage................................. 24 VAC
Power consumption ............................... 105 W
Controller protection rating ................... IP 22
Valve protection rating ........................... IP 44
Power supply .......................................... 230 VAC, 50/60 Hz, 105 VA, Class II
Transient over-voltages ......................... within the limits of category II
Pollution Degree..................................... 3
Temporary over-voltages must be limited in duration and in frequency.
Model without transformer
Warning
A switch or circuit-breaker must be included in the installation, it must be suitably located
and easily reached, it must be marked as the disconnecting device for the equipment.
Warning
The power must be achieved by a transformer in which the primary windings are separated
from the secondary windings by REINFORCED INSULATION, DOUBLE INSULATION, or a
screen connected to the PROTECTIVE CONDUCTOR TERMINAL.
Warning
It is required the installation of a fuse as over-current protection, it has to be positioned
between the system and the secondary of the transformer in the installation with the
following characteristics: V>= 30Vac, Imax=10A (ES. 10x20 10A)
Environmental conditions
• Indoor use only;
• temperature from 5°C to 40°C;
• maximum relative humidity 80% for temperatures up to 31°C decreasing linearly to 50% relative
humidity at 40°C;
• mains supply voltage fluctuations up to ±10% of the nominal voltage.

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3.1.1. Performance flow rate characteristics
The graph shows the pressure drop created by the valve itself at different flow rates. It allows
predetermining the maximum flow rate going through the valve depending on the system settings
(inlet pressure etc). It also allows to determine the valve pressure drop at a given flow rate, and
therefore to evaluate the system pressure drop vs flow rate.
3.2. Outline drawing
Flow rate [m3/h]
Single valve
Service
Backwash
Pressure drop [bar]
0.2 0.4 0.6 0.8 1.0 1.8 2.0 3.0 4.0
0
20
40
60
80
100
120
FLOW RATE VS PRESSURE DROP

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3.3. Components description and location
Lower power head
Injector
Micro-switches
Brine valve
Camshaft
Camshaft
NXT controller
Lower piston
Status LED
Setting button
Shift button
Display
Diagnostic button
Regeneration button
Inlet
Brine line
Upper power head
Drain line
Motor
Upper piston
Micro-switches
Motor
Outlet

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3.4. System regeneration cycle
Note
This valve allows DF and UF regenerations.
3.4.1. DF regeneration cycle (5-cycles operation)
Service — normal use
Untreated water is directed down through the resin bed and up through the riser tube. The hardness
ions attach themselves to the resin and are removed from the raw water being exchanged on the resin
beads by sodium ions. The water is conditioned as it passes through the resin bed.
Backwash — cycle C1
The flow of water is reversed by the valve and directed down the riser tube and up through the resin
bed. During the backwash cycle, the bed is expanded and debris is flushed to the drain, while the
media bed is remixed.
Brine draw & slow rinse — cycles C2
The controller directs water through the brine injector and brine is drawn from the brine tank. The
brine is then directed down through the resin bed and up through the riser tube to the drain. The
hardness ions on the resin beads are replaced by sodium ions and are sent to the drain. The resin is
regenerated during the brine cycle. When the air check valve closes brine drawing finishes, and then
the slow rinse phase starts.
Rapid rinse — cycle C3
The valve directs water down through the resin bed and up through the riser tube to the drain. Any
residual brine is rinsed from the resin bed, while the media bed is re-compacted.
Brine tank refill — cycle C4
Water is directed to the brine tank, at a rate controlled by the refill controller, to create brine for the
next regeneration. During brine refill, treated water is already available at the valve outlet.
Pause & Delay — cycle C5
The valve is in stand-by until the end of the cycle.
Note
The cycle Pause & Delay is optional with NXT controller. The factory value is set to 0 minute.
Note
Used in multiplex, if the brine tank is shared, to let time for the brine preparation.

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Note
For illustration purpose only. Always verify inlet and outlet marking on the valve.
From brine
tank
C2
BRINE DRAW & SLOW RINSE
C1
BACKWASH
SERVICE
NORMAL USE
C4
BRINE TANK REFILL
Valve
C5
PAUSE & DELAY
C3
RAPID RINSE
Outlet
Drain
Inlet
Valve
Outlet Inlet
Valve
Outlet Inlet
Valve
Outlet Inlet
Valve
Outlet Inlet
Valve
Outlet Inlet
To brine tank
Drain
Drain

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3.4.2. UF regeneration cycle (5-cycles operation)
Service — normal use
Untreated water is directed down through the resin bed and up through the riser tube. The hardness
ions attach themselves to the resin and are removed from the raw water being exchanged on the resin
beads by sodium ions. The water is conditioned as it passes through the resin bed.
Pause & Delay — cycle C1
The valve is in stand-by until the end of the cycle.
Note
The cycle Pause & Delay is optional with NXT controller. The factory value is set to 0 minute.
Brine draw & slow rinse — cycles C2
The controller directs water through the brine injector and brine is drawn from the brine tank. The
brine is then directed down through the riser tube and up through the resin bed to the drain. The
hardness ions are replaced by sodium ions and are sent to the drain. The resin is regenerated during
the brine cycle. Then the slow rinse phase starts.
Backwash — cycle C3
The flow of water is reversed by the valve and directed down the riser tube and up through the resin
bed. During the backwash cycle, the bed is expanded and debris is flushed to the drain, while the
media bed is remixed.
Rapid rinse — cycle C4
The controller value directs water down through the resin bed and up through the riser tube to the
drain. Any residual brine is rinsed from the resin bed, while the media bed is re-compacted.
Brine tank refill — cycle C5
Water is directed to the brine tank, at a rate controlled by the refill controller, to create brine for the
next regeneration. During brine refill, treated water is already available at the valve outlet.