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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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).

8
MGT 2” 60M–600M NXT2 TWIN ALTERNATING
INSTALLATION
BRINE TANK INSTALLATION
The brine tank should be installed on a smooth level surface. If none is available, the tank should be
placed on a smooth piece of exterior plywood and leveled by placing shims underneath the plywood.
Make sure that the salt shelf inside the tank is level and that the brine well is near to vertical as possible.
The brine valve oat is used as a safety overow and should be high on the oat rod. It is not used to stop
the rell. If the oat is near the salt shelf, move the oat up near the top of the valve.
Note: Brine valve assembly will not sit on
bottom of brine tank.
Using the tubing supplied in the brine tank,
connect one end to the brine valve in the
brine tank (“A”) to the brine injector port on
the valve (“B”). There should be an insert
and enough brine tubing to reach from the
brine valve to the control valve. For systems
that use a 1600 brine valve, the tubing will
be 3/8” OD. For systems that use the 1700
brine valve, the tubing will be 1/2” OD. 18
feet of tubing is included with the system.
A duplex system also includes a tubing tee
for connection from the brine tank to both
control valves.
After connecting the tubing on both ends,
verify that the brine line tubing is not kinked
or restricted.
Run exible tubing (not provided) from the
brine tanks over ow tting to an
appropriate, non-elevated, open drain.
Using a bucket or hose, ll brine tank with
water to about 2” above salt platform. Do not
add salt at this time.
Note:: In the process of making brine for
the rst regeneration, the solution volume
will increase (one gallon of water will be 1.2
gallons of brine). The nal level of the liquid
will be several inches above the platform.
RECOMMENDED TYPES OF SALT
Only puried salt should be used in the brining
system. Palletized salt (“Button”, “Nugget”, and
“Pellet”) or block salt (free binders) is recom-
mended. Do not use granulated salt, as it will fall
through the platform screen.
Rock salt is not normally recommended. Most
rock salt contains sludge-forming insoluble that
collect on the platform and prevents proper
salt-water contact.
Only salt containing 0.5% or less of insolubles
will provide continued satisfactory operation.
If salt with more insolubles is used, the brine
maker will require periodic cleaning.
B
2 - TOP VIEW OF CONTROL VALVE
1 - BRINE SYSTEM
B
A

9
MGT 2” 60M–600M NXT2 TWIN ALTERNATING
INSTALLATION
MOUNTING WATER METER ASSEMBLY (IF UNIT IS NOT SKID MOUNTED)
1. Locate the meter. The meter may or many not have the cable attached. If not, locate the cable as well.
2. For a twin alternating system, the meter must be installed in the common outlet of the softeners. Refer to the Gen-
eral Arrangement drawing on page two (2). The water meter has a ow arrow stamped on it. The ow arrow on the
meter should be pointing away from the softeners.
3. After installing the meter, insert the meter end of the cable into the meter dome if necessary. Then run the meter
cable along the piping back to the unit 1 control valve.
4. Run the cable through a cable grip and into the back of the control and into the controller. Connect the meter cable
to the circuit board in the lower right as shown.
System 7 Twin Alternating
CAT 5 CABLE
UNIT 1 UNIT 2
NETWORK/COMMUNICATION CABLES & CONNECTIONS
Use either a CAT3 or CAT5 Network/Communication cable.
1. Connect the network/communication cable rst before programming.
2. The maximum cable length between timers is 100 feet.
3. Connect each unit in series (do not form a loop) from one communication port to the next communication port. It
does not matter which one goes to the next one.
The number of network/communication cables needed for setup is one less than the total number of valves.
Two-Unit System: One network/communication cable
Three-Unit System: Two network/communication cables
Four-Unit System: Three network/communication cables
NETWORK TIMER SYSTEM 7 TWIN ALTERNATING CONFIGURATION WIRING
COMMUNICATION PORTS
FLOW METER CONNECTION

10
MGT 2” 60M–600M NXT2 TWIN ALTERNATING
INSTALLATION
INSTALLATION OF CONNECTION PIPING
NOTE:
• Use thread sealing tape on all threaded piping connections.
• Install the piping conforming to federal, provincial, and local codes.
• Union or anges are recommended at the control valve’s inlet, outlet, and drain connections
• To enhance the monitoring of the system’s performance sample valves and pressure gauges can be installed at
the inlet and outlet piping to each control valve.
Caution: All piping must be properly supported. The tank and valve assemblies are not meant to support the
connecting piping.
1. Install piping as shown on installation diagram. It is recommended that unions be installed on inlet and outlet
connections to facilitate service of unit. Be sure piping is free of thread chips and other foreign matter. The
connecting piping should be the same size or larger then the service inlet and outlet of the control valve. On
multiple units that are both in service at the same time the common service inlet and outlet headers should be
up-sized to accommodate the total ow
2. Verify that the ow arrow stamped on the brass ow controller is pointing away from the control valve. See
installation diagram or valve manual for the location. Install a drain line from backwash control assembly to an
appropriate drain using a minimum of elbows. Install a union near the backwash control to facilitate cleaning. Do
not install a valve on the drain line.
NOTE:
• If distance of drain line is over a 10 ft. vertical or 25 ft. horizontal run, increase drain line one pipe size over that
provided on the control valve.
• Do not make a direct connection to the drain. Provide an air gap of at least four times the diameter of the pipe to
conform to sanitation codes and to permit observation of the ow.
• It is not recommended that an overhead or a long horizontal drain run be used. The increase of backpressure will
cause problems when drawing brine.
POWER SUPPLY INSTALLATION
NOTE: POWER SUPPLY INCLUDES A HARNESS WITH 2 BLACK WIRES THAT CONNECT TO THE CIRCUIT BOARD.
1. Insert black and black transformer wires into 24VDC input of control.
2510/2750/2815/2850/2900 Valves:
Communication Cables
Power Supply
Meter Cable
Wire Harness
Hinge Mount: mount per valve model noted

11
MGT 2” 60M–600M NXT2 TWIN ALTERNATING
OPERATION
TIMER DISPLAY FEATURES
Display Icons
Valve State: Service
Valve State: Standby
Flow Indicator (flashing)
Regeneration
Master Unit (auto-assigned)
Network Indicator - Connected
Network Indicator - Disconnected
Network Indicator - Unit Missing
USB Connected (Field Programmer)
Error Condition Present
Remote Lock
Lock Window
Initializing
Upper Drive Movement
Lower Drive Movement
Remote Regeneration
Master Programming
User Programming
Diagnostics
Time of Day Programming
System
Number
Network
Indicator
Valve
State
Flow
Indicator
Time
of Day
Master
Indicator
Status
LEDs
Display Screen
Alternates between
Date, Flow Rate, and
Volume Remaining
(If a regeneration is
queued, displays time
until regeneration)
Left Button
Press:
Navigate to previous
menu option
Press and Hold:
Enter Diagnostic menu
Blue LED
On - Unit in Service
Blinking - Regeneration Queued
Green LED
On - Unit in Regeneration
Blinking - Unit in Standby
Red LED
On - Error present
Down Button
Press:
Adjust menu value down
Press and Hold:
Enter Time of Day menu
Up Button
Press:
Adjust menu value up
Press and Hold:
Enter Time of Day menu
Left Button + Down Button
Press and Hold -
Enter Master Programming
Down Button + Up Button
Press and Hold -
Enter User Programming
Extra Cycle Button
Press:
Navigate to next
menu option
Press and Hold:
Initiate a regeneration

12
MGT 2” 60M–600M NXT2 TWIN ALTERNATING
OPERATION
TIMER OPERATION
TIMER OPERATION DURING PROGRAMMING
The timer enters the Program Mode in standby or service mode as long as it is not in regeneration. While in the
Program Mode the timer continues to operate normally monitoring water usage. Timer programming is stored in
memory permanently.
TIMER OPERATION DURING A POWER FAILURE
All program settings are stored in permanent memory. Current valve position, cycle step time elapsed, and time of
day are stored during a power failure, and will be restored upon power re-application. Time is kept during a power
failure, and time of day is adjusted upon power up (as long as power is restored within 12 hours).
NOTE:
The time of day on the main display screen will ash for 5 minutes when there has been a power outage.
The ashing of the time of day can be stopped by pressing any button on the display.
REMOTE LOCKOUT
The timer does not allow the unit/system to go into Regeneration until the Regeneration Lockout Input signal to
the unit is cleared. This requires a contact closure to activate the unit. The recommended gauge wire is 16 AWG with
a maximum wire length run of 50 feet.
REGENERATION DAY OVERRIDE FEATURE
If the Day Override option is turned on and the valve reaches the set Regeneration Day Override value, the
Regeneration Cycle starts if no other unit is in Regeneration. If other units are in regeneration, it is added to a
regeneration queue. This occurs regardless of the remaining volume available.
FLOW METER EQUIPPED TIMER
As treated water is used, the Volume Remaining display counts down from the calculated system capacity to zero.
When zero is reached, a Regeneration Cycle begins if no other units are in regeneration.
SYSTEM OPERATION
System 7 (2 Units) Alternating Immediate
One tank online supplying treated water, one tank in Standby. Only #1 control will monitor its ow meter/sensor input.
Regeneration of a unit will begin after the other control has left Standby and returned to Service. When the Regenera-
tion cycle is complete, the regenerated unit will enter Standby. Standby on each tank is controlled by the relay on the
NXT2 circuit board.

13
MGT 2” 60M–600M NXT2 TWIN ALTERNATING
OPERATION
TIMER OPERATION
SETTING THE TIME OF DAY
NOTE: Set Time of Day on any unit and the rest of the units in the system will update the Time of Day automatically.
1. Press and hold the Up button for 2 seconds. The “Time” value is displayed. Press the Up or Down buttons to adjust as desired.
2. Press the Extra Cycle button to advance to the “Year” eld. Press the Up or Down buttons to adjust as desired.
3. Press the Extra Cycle button to advance to the “Month” eld. Press the Up or Down buttons to adjust as desired.
4. Press the Extra Cycle button to advance to the “Calendar Day” eld. Press the Up or Down buttons to adjust as desired.
5. Press the Extra Cycle button to return to the normal display screen.
NOTE: Press and hold the Left button to exit without saving.
MANUALLY INITIATING A REGENERATION
1. When timer is In Service or Standby, press and hold the Extra
Cycle button on the main screen.
2. The timer advances to Regeneration Cycle Step #1, and begins
programmed time count down.
3. Press the Extra Cycle button once to advance valve to
Regeneration Cycle Step #2 (if active).
4. Press the Extra Cycle button once to advance valve to
Regeneration Cycle Step #3 (if active).
5. Press the Extra Cycle button once to advance valve to
Regeneration Cycle Step #4 (if active).
6. Press the Extra Cycle button once to advance valve to
Regeneration Cycle Step #5 (if active).
7. Press the Extra Cycle button once more to advance the
valve back to In Service.
NOTE: A manually initiated or queued regeneration can be
cleared by pressing and holding the Back button. A system
queued regeneration can only be cleared by stepping through
a manual regeneration. If regeneration occurs for any reason
prior to the delayed regeneration time, the manual regenera-
tion request shall be cleared. Pressing the Extra Cycle button
while in regeneration will cause the upper drive to advance to
the next step immediately.
In the Regeneration Cycle step display, the timer shows the current regeneration cycle name the valve is in, or has
reached, and the time remaining in that step. Once all regeneration steps are complete, the timer returns to In Service
and resumes normal operation.
Press the Extra Cycle button during a system queued Regeneration Cycle to immediately advance the valve to
the next cycle step position and resume normal step timing.
LOCK SETTINGS (ACCESS TO MASTER PROGRAMMING)
Lock Settings prevents the user from accessing Master Programming. In Master Programming, select the desired
Lock Settings option (Off, Time Based, Delayed, or Enter Code).
Time Based - User must set clock to 12:01 pm to unlock
Delayed - User must press and hold the Left and Down buttons for 60 continuous seconds to unlock
Enter Code - User must input code “1201” to unlock
SETTINGS REVIEW
To prevent unintentional changes to Master Programming, enable Settings Review to view and navigate through
Master Programming settings without the ability to edit.

14
MGT 2” 60M–600M NXT2 TWIN ALTERNATING
OPERATION
START-UP PROCEDURES
Again, make sure all plumbing is complete and tight, including drain line and brine line. Make sure all electrical
components, including the communication cables (multi tank systems only) are properly installed and connected.
1. Using a bucket or hose, ll brine tank with water to 2” above salt platform. Do not add salt at this time.
2. Make sure inlet and outlet isolation valves are closed, and then turn on power to the system.
Note: Start up only one (1) tank at a time.
3. Open the manual bypass valve. The manual inlet and outlet valves are to remain closed.
4. Connect electrical power to the control valve by plugging in the valve. Once the valve is powered it will drive to the
service position. The LED light should be blue.
5. Program the NXT2 controller. The water hardness, day override, time of regeneration, and time of day will need to
be set on site to the desired settings. (Refer to the User Mode Programming section of the manual.) The softener
settings are pre-programmed at the factory. Instructions for changing these settings are in the Master
Programming Guide section.
6. Manually initiate a regeneration by pressing and holding the Extra Cycle button on the NXT2 controller.
7. The LED light on the NXT2 timer should change from Blue indicating the unit is In Service color to Green
indicating the unit is in Regeneration.
8. Slowly open the manual inlet supply valve of the unit that is in backwash. Do not open the valve fully. Water will
enter from the bottom of the mineral tank as air is expelled from the top to the drain. Full ow of water could cause
loss of mineral. Continue to ll slowly until all air is expelled and only water ows to the drain.
9. When only water ows to the drain, open the inlet valve fully and backwash the unit until the water looks clean
when caught in a container.
10. Press the Extra Cycle push button to advance the valve to the Brine/Rinse position.
11. While the unit is in the brine/rinse position, check the level in the brine tank. The level should be dropping at
a slow rate (approximately 2” per minute). Allow the level to drop until the air check valve closes.
12. Press the Extra Cycle push button to advance the valve to the Fast Flush position. Allow the water to ow to the
drain until clear.
13. Press the Extra Cycle push button to advance the valve to the Brine Tank Rell position. Allow the brine tank to ll
with water for the duration of the step. The water level should be 1”-2” inches above the salt platform.
14. Press the Extra Cycle push button to advance the valve to the Service/Standby position.
15. If applicable repeat steps 3 - 13 for the other unit(s).
16. Fill the brine tank with the proper amount and type of salt recommended for use with the system.
17. Close the manual bypass valve and open all outlet valves fully. The system is now in service.
Program Notes:
• The valve programmed as initially will be the Lead unit.
• The Meter must be connected to the Lead unit.- Unit 1

15
MGT 2” 60M–600M NXT2 TWIN ALTERNATING
OPERATION
USER MODE PROGRAMMING FLOW CHART
1. To navigate, press the Extra Cycle button to advance to the next value. Press the Left button to retreat to the
previous value.
2. Where applicable, use the Up and Down buttons to adjust a value as desired.
3. After progressing through all available values, the timer will return to Normal operation.
4. Depending on the current controller programming, certain values may not be able to be viewed or set.
5. The timer will display local information, not system information.
1. Enter User Mode
Press and hold the Up and Down buttons for 3 seconds.
2. Set Regeneration Day Override/Time Driven
To turn on and set the days, press the Up or Down button. Range is OFF to 99 days.
Press the Extra Cycle button to proceed to the next step.
3. Set Regeneration Time
Press the Up and Down buttons to change the time value. Holding a button down will speed through the setting.
Press the Extra Cycle button to proceed to the next step.
4. Set Feed Water Hardness
Press the Up and Down buttons to change the value of the numbers. Press the Extra Cycle button to to proceed to
the next number. Range is 0-999 gpg. After the third number is entered,pressing the Extra Cycle button will
continue to the next step.
NOTE: Only displayed when a metered option is chosen under System Type.
5. Set Volume Remaining
Press the Up and Down buttons to change the value of the numbers. Press the Extra Cycle button to proceed to
the next number. Range is 0-99,999 gallons. After the last number is entered, pressing the Extra Cycle button will
end User Mode.
To exit user mode, progress through all available values, or press and hold the Left button at anytime, or after
5 minutes of inactivity the timer will return to normal operation automatically.
6. End of User Programming Mode

16
MGT 2” 60M–600M NXT2 TWIN ALTERNATING
OPERATION
BATCH SIZE CALCULATION
Batch size is the term used for the amount of water being softened by the water softener between regenerations. The
NXT2 controller calculates this value automatically based on the values in the program. This is a simple calculation
provided two pieces of information are known:
Capacity of the water softener in grains (gr.)
(i.e. MGT-300 has 300,000 grains capacity per tank).
Hardness of the raw water being treated by the water softener.
BATCH SIZE EQUATION:
Grain Capacity of Softener
Batch Size = Hardnessof Water (grains per gallon)
SAMPLE CALCULATION
Assume:
Unit is a model MGT-300 softener
The hardness of the water was measured to be 20 grains per gallon
Using our equation take 300,000 ÷ 20 = 15,000 gallons.
10% Safety factor - reserve capacity = 1,500 gallons.
15,000 gallons – 1,500 gallons = 13,500 gallons (batch size)
For immediate regeneration type meter control the meter setting would be at 15,000 gallons. Commonly this value is
adjusted to 90 percent of the actual value (in this example 13,500 gallons) to assure not over-running the softener.
NOTE:
For meter delayed options, the batch size is determined as in our example, except an additional amount of gallons
must be accounted for and deducted from the total to allow soft water to be available until the softener regenerates
at the selected delay time of day or night. This compensation is necessary since the meter will indicate regeneration
required time prior to the set delay time. This can be accomplished on the NXT2 timer by increasing the safety factor
in the Master Programming mode.

17
MGT 2” 60M–600M NXT2 TWIN ALTERNATING
OPERATION
DIAGNOSTIC MODE FLOW CHART
Entering Diagnostic Mode:
1. Press and hold the Left button to enter Diagnostic Programming
mode.
2. To navigate, press the Extra Cycle button to advance to the next
value. Press the Left button to retreat to the previous value.
3. To reset/clear a value (such as Totalizer or Error Log), while on
the value, press and hold the Up and Down buttons simultaneously.
5. After progressing through all available values, the timer will
return to Normal operation.
6. To exit diagnostic mode, press and hold the Left button at
anytime or after 5 minutes of inactivity the timer will return to
normal operation automatically.
7. Depending on the current controller programming, certain
values may not be able to be viewed or set.
8. The timer will display local information, not system information.
9. In the event of a regeneration occurring while displaying
diagnostics, the regeneration step and time remaining will be
displayed. When regeneration has been completed, the
display will return to the main screen.
Example:
Real-time flow rate reading.
FLOW RATE
29.7 GPM
Example:
Peak flow since last regeneration.
PEAK FLOW
30.1 GPM
Example:
Gallons at the outlet since installation.
TOTALIZER
482474 G
Example:
Reserve Capacity setting.
RESERVE
1588 G
Example:
Gallons at the outlet since last regeneration.
USE SINCE REGEN
7331 G
Example:
Time since last regeneration.
LAST REGEN.
4 H
Example:
Installed software version.
SOFTWARE VERSION
13026
Example:
Total number of regenerations since installation.
NO. OF REGENS
32
Example:
Duration between regenerations.
REGEN INTERVAL
3 D 21 H
Example:
Last time programming settings were changed.
LAST SETTINGS CHANGE
14 H 0 M
Example:
Record of error events chronologically.
ERROR LOG
ERROR LOG EMPTY
SUN-DAILY USAGE
2017-10-10 0 G
2017-01-02 0 G
2017-12-26 0 G
Example:
Average usage from past Sunday.
SUN-AVERAGE USAGE
29.7 G
Example:
Average usage from past 3 Sundays.
MON-DAILY USAGE
2016-10-10 0 G
2017-01-02 0 G
2016-12-26 0 G
Example:
Average usage from past Monday.
MON-AVERAGE USAGE
29.7 G
Example:
Average usage from past 3 Mondays.
TUE-DAILY USAGE
2016-10-10 0 G
2017-01-02 0 G
2016-12-26 0 G
Example:
Average usage from last Tuesday.
TUE-AVERAGE USAGE
29.7 G
Example:
Average usage from past 3 Tuesdays.
WED-DAILY USAGE
2016-10-10 0 G
2017-01-02 0 G
2016-12-26 0 G
Example:
Average usage from last Wednesday.
WED-AVERAGE USAGE
29.7 G
Example:
Average usage from past 3 Wednesdays.
THU-DAILY USAGE
2016-10-10 0 G
2017-01-02 0 G
2016-12-26 0 G
Example:
Average usage from last Thursday.
THU-AVERAGE USAGE
29.7 G
Example:
Average usage from past 3 Thursdays.
FRI-DAILY USAGE
2016-10-10 0 G
2017-01-02 0 G
2016-12-26 0 G
Example:
Average usage from last Friday.
FRI-AVERAGE USAGE
29.7 G
Example:
Average usage from past 3 Fridays.
SAT-DAILY USAGE
2016-10-10 0 G
2017-01-02 0 G
2016-12-26 0 G
Example:
Average usage from last Saturdays
SAT-AVERAGE USAGE
29.7 G
Example:
Average usage from past 3 Saturdays.
END