MARLO NXT2 Series User manual

MGT 60M – 600M
SYSTEM 7 – TWIN ALTERNATING
2” NXT2 SERIES
MODEL NO:
SERIAL NO:
DATE INSTALLED:
DEALER:
COMPLETE FOR FUTURE REFERENCE:
Standard Photograph
Equipment appearance may differ.
Twin system shown with skid mount option.
COMMERCIAL WATER CONDITIONER
INSTALLATION, OPERATION, AND MAINTENANCE MANUAL
8-633

MGT 2” 60M–600M NXT2 TWIN ALTERNATING
Inspection Requirement
Prior to Loading Media
1. Inspect condition of upper distributor piping. Verify
fittings are tight and positioned as shown.
2. Inspect condition of strainers, laterals and hub through
top or side access ports. Verify fittings are secured
to hub.
3. DO NOT load media if damaged components are
observed. Contact factory.
4. Installer is responsible for media loss into treated water
resulting from failure to report and repair damaged
components inside media tank prior to media loading.
5. INSTALLER WARNING:
Refer to installation instructions for media loading
procedure. Improper loading of media will damage
components inside media tank.
PRIOR TO
Media Loading
AFTER
Media Loading
SIDE
VIEW
Lateral
Hub
Distributor Tube
Media Tank
Softener/
Filter Media
Gravel
Media
TOP
VIEW
Media Tank
Lateral
Hub
5-272
IMPORTANT PLEASE READ:
• Warranty of this product extends to manufacturing defects.
• The information, specications and illustrations in this manual are based on the latest information
available at the time of printing. The manufacturer reserves the right to make changes at any time
without notice.
• This product should be installed by a plumbing professional on potable water systems only.
• This product must be installed in compliance with all local and state and municipal plumbing and
electrical codes. Permits may be required at the time of installation.

MGT 2” 60M–600M NXT2 TWIN ALTERNATING
TABLE OF CONTENTS
SYSTEM INFORMATION
Product Warranty...........................................................................................................................................................1
General Arrangement Drawings ....................................................................................................................................2
Dimension Chart ...........................................................................................................................................................4
Specication Chart .......................................................................................................................................................5
INSTALLATION
General Information.......................................................................................................................................................6
Loading Softener ..........................................................................................................................................................7
Mounting Control Valve ................................................................................................................................................7
Brine Tank Installation ...................................................................................................................................................8
Mounting Water Meter ...................................................................................................................................................9
Network Communication Cables/Connections ..............................................................................................................9
Power Supply Wiring ...................................................................................................................................................10
Connection Piping Installation .....................................................................................................................................10
OPERATION
Timer Display Features ............................................................................................................................................... 11
System Operation........................................................................................................................................................12
Timer Operation...........................................................................................................................................................12
Start-Up Procedures....................................................................................................................................................14
User Mode Programming Flow Chart..........................................................................................................................15
Batch Size Calculation.................................................................................................................................................16
Diagnostic Mode Flow Chart .......................................................................................................................................17
Master Programming Flow Chart.................................................................................................................................18
Master Programming Guide ........................................................................................................................................20
Flow Diagrams.............................................................................................................................................................21
Wiring Diagram............................................................................................................................................................27
MAINTENANCE
Powerhead Assembly .................................................................................................................................................28
NXT2 Timer Assembly.................................................................................................................................................30
Control Valve Assembly...............................................................................................................................................31
Brine Injector Assemblies ...........................................................................................................................................33
Meters and Flow Sensors ...........................................................................................................................................36
Brine Tank Assemblies ...............................................................................................................................................41
Service Assemblies ....................................................................................................................................................45
Troubleshooting...........................................................................................................................................................46

MGT 2” 60M–600M NXT2 TWIN ALTERNATING
SYSTEM INFORMATION
1
COMMERCIAL AND INDUSTRIAL PRODUCT WARRANTY
Manufacturer warrants all commercial and industrial water treatment products manufactured and/or distributed by it to
be free from defects in materials and workmanship for a period of one (1) year after installation or eighteen (18)
months from the date of shipment, whichever comes rst. The berglass mineral tank(s) alone have a warranty for a
period of ve (5) years from the date of shipment. If within that period any products shall be proven to Manufacturer’s
satisfaction to be defective, those products will be replaced or the price refunded at Manufacturer’s option.
Manufacturer’s obligations or nonperformance, defective, or any damage caused by its products or their use, and
buyer’s exclusive remedy therefore, shall be limited to product replacement or refund and shall be conditioned upon
Manufacturer’s receiving written notice together with a demand for such replacement or refund:
The foregoing warranty is exclusive and in lieu of all other expressed implied warranty (except of title) including but
not limited to implied warranty of merchantability and tness for particular purpose.
Manufacturer will not be subject to and disclaims the following:
1. Any other obligations or liabilities arising out of breach of contract or out of warranty.
2. Any obligations whatsoever arising from tort claims (including negligence and strict liability or arising under other
theories of law with respect to products sold or services rendered by Manufacturer or any undertakings, acts, or
omissions relating thereto.
3. All consequential, incidental, and contingent damages.
Labor charges, charge backs or handling charges are excluded from Manufacturer’s warranty provisions.
COMMERCIAL AND INDUSTRIAL WATER SOFTENER GUARANTEE
Under normal operating conditions:
1. The softener efuent shall be zero soft as determined by a soap test.
2. The loss of softening resin through attrition during the rst three (3) years shall not exceed 3% per year.
3. The softening resin shall not be washed out of the system during backwash.
4. The color and turbidity of the softener efuent shall not be greater than the incoming water.

MGT 2” 60M–600M NXT2 TWIN ALTERNATING
SYSTEM INFORMATION
2
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5-232

MGT 2” 60M–600M NXT2 TWIN ALTERNATING
SYSTEM INFORMATION
3
FRONT VIEW
BACK VIEW
1 1
2 2
3 3
4 4
5 5
6 6
7 7
8 8
DATE FRAC.
DRN.
APP'D.
DEC.
DRAWING NO.
SCALE
FILE ID.
SHEET
REV.
OF
MGT-300-2 TW-ALT SKID - PVC
GENERAL ARRANGEMENT
11
2/18/2010 1
REVISIONS
NO. BY REMARKS
112/13/13 AJJG ADDED VACUUM RELIEF VALVES
DATE
RESIN TANK (RT) BRINE TANK (BT)RESIN TANK (RT)
A A
B B C C
D D
L
W
H
AUTOMATIC BACKWASH
FLOW CONTROLLER
BY-PASS VALVE
(NORMALLY CLOSED)
RAW WATER
INLET 30-100 PSIG
SOFT WATER OUTLET
FLOW METER
INLET ISOLATION
VALVE
OUTLET ISOLATION
VALVE
OVER FLOW
TO DRAIN
WATER INLET
PRESSURE GAUGE
AND SAMPLE COCK
(TYP.)
WATER OUTLET PRESSURE GAUGE AND SAMPLE COCK
(TYP.)

MGT 2” 60M–600M NXT2 TWIN ALTERNATING
SYSTEM INFORMATION
4
DIMENSION CHART
MODEL INLET SIZE
(Inches)
TANK SIZE LENGTH
(Inches)
WIDTH
(Inches)
HEIGHT*
(Inches)
SOFTENER
(Inches)
BRINE
(Inches)
60 2 12x52 18x40 64 18 69
90 2 14x65 18x40 66 18 79
120 2 16x65 24x40 77 24 79
150 2 18x65 24x50 82 24 81
210 2 21x62 24x50 83 24 81
240 2 24x72 24x50 89 24 88
270 2 24x72 24x50 89 24 88
300 2 24x72 24x50 89 24 88
450 2 30x72 30x50 107 30 89
600 2 36x72 39x48 129 39 89
*Leave a minimum 24 inch clearance to the height of the unit for loading media.
Dimensions are for general arrangement use only.

MGT 2” 60M–600M NXT2 TWIN ALTERNATING
SYSTEM INFORMATION
5
SPECIFICATION CHART
SYSTEM SIZE
MODEL 60 90 120 150 210 240 270 300 450 600
VALVE SIZE (IN) 2222222222
MAX CAPACITY (KILOGRAINS) 60 90 120 150 210 240 270 300 450 600
MIN CAPACITY (KILOGRAINS) 40 60 80 100 140 160 180 200 300 400
FLOWRATE (GPM)
CONTINUOUS FLOWRATE (GPM) 33 39 47 61 60 74 71 68 84 87
PEAK FLOWRATE (GPM) 49 54 64 80 77 97 94 91 105 110
BACKWASH & FAST FLUSH (GPM) 3.5 5 6 8 12 15 15 15 25 30
BRINE DRAW & RINSE (GPM) 1 1 1.2 1.5 2.8 3.2 3.2 3.2 4.7 4.7
BRINE TANK REFILL (GPM) 1112222255
TIMER
SETTINGS
BACKWASH & FAST FLUSH (MIN) 10 10 10 10 10 10 10 10 10 10
BRINE DRAW & RINSE (MIN) 60 60 60 60 60 60 60 60 80 80
FAST FLUSH (MIN) 10 10 10 10 10 10 10 10 10 10
BRINE TANK REFILL (MIN) 10 15 20 13 18 20 23 25 15 20
SOFTENER
TANK
SIZE (IN) 13x54 14x65 16x65 18x65 21x62 24x72 24x72 24x72 30x72 36x72
GRAVEL (LBS) 0 30 35 40 80 120 120 120 225 400
RESIN (FT3)2 3 4 5 7 8 9 10 15 20
FREEBOARD (IN) 16 21 21 24 18 30 25 21 22 23
BRINE SYSTEMS
EQUIPMENT
TANK SIZE 18x40 18x40 24x40 24x50 24x50 24x50 24x50 24x50 30x50 39x60
MAX SALT STORAGE (LBS) 270 270 530 630 540 510 490 410 640 1700
INJECTOR CODE 3 3 4 3C 4C 5C 5C 5C 6C 6C
INJECTOR COLOR YEL YEL GRN YEL GRN WHT WHT WHT RED RED
MAX
SALT DOSAGE- MAX (LBS) 30 45 60 75 105 120 135 150 225 300
REFILL TIME - MAX (MIN) 10 15 20 13 18 20 23 25 15 20
MIN
SALT DOSAGE- MIN (LBS) 12 18 24 30 42 48 54 60 90 120
REFILL TIME - MIN (MIN) 46857891068
REGENERATION WASTE VOLUME (GAL) 126 156 188 228 366 520 536 544 860 1020
NOTES:
1. FLOW RATES
Continuous: pressure loss does not exceed 15 psig.
Peak: pressure loss does not exceed 25 psig
Backwash & Flush: maximum flow to drain
Brine & Rinse: Injector flow to drain
Brine Tank Refill: flow to refill Brine Tank
2. SOFTENER TANK
Freeboard: distance in inches from surface of resin to top sealing flange of tank
3. SALT DOSAGE
Maximum 15 lbs./cu.ft. - regeneration efficiency: 2,000 grains/pound of salt
(factory setting)
Maximum 6 lbs./cu.ft. - regeneration efficiency: 3,000 grains/pound of salt
4. REGENERATION WASTE VOLUME - Total gallons water discharged per
regeneration
5. OPERATING LIMITS:
Minimum operating pressure is 30 psi.
Maximum operating pressure is 120 psi.
Standard units are designed to soften unheated water within the range of
35-100°F.
6. POWER
Power requirements are 120 Volt, 60 Hertz, Single Phase, 2 amps
noninterrupted.
7. SALT
Salt specifications are pelletized or solar salt, 99% pure, containing
less than 1% insolubles (see Brine Tank Installation on page 8)

6
MGT 2” 60M–600M NXT2 TWIN ALTERNATING
INSTALLATION
INSTALLATION INSTRUCTIONS WATER SOFTENERS
GENERAL INFORMATION
1. Operating pressure range is 30-100 psi. If pressures over 100 psi are encountered, a regulator must be installed.
NOTE: The control valve will not operate correctly if feeding into an atmospheric tank. A pressure control device
must be added to the outlet to maintain the minimum pressure.
2. Power requirements are shown on inside cover of the control valve. You can also tell by wire color on the motor:
Black wires are 115 volt. Yellow wires are 220 volt. Blue wires are 24 volt.
3. Standard units are designed to soften unheated water not to exceed 100F. Special valve assemblies are available
to handle heated water supplies exceeding 100 F. Consult factory if applicable.
4. Each softener tank is shipped with distributor manifold and control valve preassembled. Take care when uncrating
and erecting so that no items are damaged.
5. The distributor assembly has been shipped inside the berglass mineral tank. Check to make sure that there is no
damage to the riser pipe, baskets, laterals, or hub prior to loading media.
NOTE: A prelter should be used on installations in which free solids are present.
LOCATE SOFTENER
1. Select a location that is accessible and near a oor drain that has adequate carrying capacity to handle
the softener regeneration ow. See specication table for the ow rate. Allow a minimum of 24” above the
tank for loading media.
2. Erect the softener tank(s) on a concrete or other rm foundation and level
NOTE: If the system is skid mounted, it may be prepiped and preloaded at the factory. Skip the following instructions
and go to the section “Installation of Connection Piping” if unit is preloaded.
3. Position the brine tank according to the illustration and supplementary brine tank information. Keep the brine tank
as close as possible to the softener tank(s).
NOTE: The distance between the softener and brine tanks will affect the brine injector performance, as the distance
increases the injector performance decreases. This may cause an inadequate regeneration. Maximum
recommended distance is 5 ft.
4. A grounded electric receptacle is required for the control valve transformer.

7
MGT 2” 60M–600M NXT2 TWIN ALTERNATING
INSTALLATION
LOAD SOFTENER TANK
IMPORTANT: Be sure to visually inspect the lower laterals prior to loading the media. Check to make sure
each lateral is rmly threaded into the hub.
1. Fill a tank approximately 1/3 full of water using a hose, bucket, etc. Plug the
PVC distributor manifold pipe using a plastic cap, cork, rag, etc. No gravel or
resin should go into this distributor manifold pipe.
2. Verify the distributor manifold is center in the tank with the distributor resting
on the bottom of the tank. Verify the riser pipe is still plugged.
NOTE: Reference the specication table in the front of this manual for the cor-
rect quantities of gravel and resin. These quantities are for each tank. Make sure
you have the required amounts on site before you begin.
3. With care not to damage any lateral, pour in the gravel provided for each
tank through the top opening in the tank and level out evenly. This will cover
the distributor assembly.
NOTE: Wetting the gravel in the bags before loading will eliminate the normal
amount of dust.
4. When gravel is loaded and leveling is completed, proceed as follows:
5. With the distributor riser pipe still plugged, add the proper amount of resin
supplied for each tank through the top
opening in the tank.
CAUTION: The softener resin is very slippery. Take care when stepping on any spilled resin. Remove spilled
resin from standing surface immediately.
6. When loading is complete, remove plastic cap, cork, or rag that was used to plug the distributor riser pipe. Be
careful not to let any foreign debris fall into the pipe. The result could be damage to system.
7. Repeat instruction steps 1-7 for each softener tank if applicable.
MOUNT CONTROL VALVE ASSEMBLY
1. Verify that the distributor riser pipe is not plugged.
2. Lubricate the distributor o-ring on the bottom of the control valve with silicone.
3. Insert disperser in threaded base of control valve. The threaded base has a groove machined into the inside of the
threaded part of the base to allow for the installation of this disperser.
4. Screw control valve into top opening of tank making sure the distributor riser pipe slides easily through the
distributor o-ring. Care must be taken not to “nick” this o-ring as hard water leakage could result.
5. Tighten down the control valve to ensure positive o-ring seal at top of tank.
6. Repeat instruction steps 1-5 for each softener tank (if applicable).