Mokon Duratherm User manual

MOK1000C 02/17
INSTRUCTION MANUAL
Circulating Water Temperature Control System
Models Covered:
Duratherm, Hydrotherm II, & Minitherm
2150 Elmwood Avenue - Buffalo, NY 14207
P# 716-876-9951 - F#716-874-8048 - www.mokon.com

i
Table of Contents
Section 1 –Warnings and Cautions ............................................... 1
1.1 Electrical Warning.......................................................................................................................1
1.2 Hot Fluid Warning.......................................................................................................................1
1.3 Cold Weather Caution..................................................................................................................1
1.4 Excessive Supply Pressure Caution.............................................................................................1
Model: DN, DO, DP, DQ, DR, DT, DU, DV, DW, DX, DY, DZ, HN, HR, HW, HX, HY, HZ,
MT ......................................................................................................................................................1
1.5 Excessive Supply Pressure Caution.............................................................................................2
Models: DA, DB, DC, DD, DE, DF, DG, DH, DJ, DK, DL, DM......................................................2
1.6 Overhead Piping Warning............................................................................................................2
1.7 Short Circuit Current Rating Caution..........................................................................................2
1.8 No Flow Warning ........................................................................................................................2
1.9 Non-Potable Water System..........................................................................................................2
Section 2 –Installation ............................................................... 3
2.1 Unpacking....................................................................................................................................3
2.2 Location .......................................................................................................................................3
2.3 Warnings......................................................................................................................................4
2.4 Electrical Connections.................................................................................................................4
2.5 Water Connections.......................................................................................................................5
Section 3 –Operation ................................................................. 6
3.1 Initial Starting Procedure.............................................................................................................6
3.2 Process Flow Adjustment ............................................................................................................6
3.3 Changing Temperature Settings...................................................................................................7
3.4 Shut Down Procedure..................................................................................................................7
3.5 Restarting Procedure....................................................................................................................7
Section 4 –Maintenance and Service............................................. 8
4.1 Preventative Maintenance............................................................................................................8
Electrical Preventative Maintenance ..................................................................................................9
Pump/Motor and Mechanical Connections Preventative Maintenance............................................10
Miscellaneous Preventative Maintenance.........................................................................................11
4.2 Pump Maintenance.....................................................................................................................13
Models: DN, DO, DR, DT, DU, DW, DY, DZ, HN, HR, HW, HX, HY, HZ .................................13
Exploded View Drawing Models: DN, DO, DR, DT, DU, DW, DY, DZ ....................................13
Exploded View Drawing Models: HN, HR, HW, HX, HY, HZ....................................................14
Seal Replacement/Maintenance.....................................................................................................15
Models: DP, DQ, DV, DX................................................................................................................17
Exploded View Drawing................................................................................................................17
Seal Replacement/Maintenance.....................................................................................................18
Models: DB, DC, DF, DG, DJ, DL ..................................................................................................20
Exploded View Drawing................................................................................................................20
Seal Replacement/Maintenance.....................................................................................................21

ii
Mounting the Motor to the Pump...................................................................................................22
Impeller Removal...........................................................................................................................23
Inspection.......................................................................................................................................23
Impeller Clearance Adjustment .....................................................................................................23
Models: DA, DD, DE, DH, DK, DM ...............................................................................................24
Exploded View Drawing................................................................................................................24
Seal Replacement/Maintenance.....................................................................................................25
Model: MT........................................................................................................................................27
Exploded View Drawing................................................................................................................27
Seal Replacement/Maintenance.....................................................................................................28
4.3 Cooling Solenoid Valve Maintenance.......................................................................................30
4.4 Low Pressure Safety Switch ......................................................................................................30
4.5 High Temperature Safety Switch...............................................................................................30
4.6 Heater Assembly........................................................................................................................31
Models: DA, DB, DC, DD, DE, DF, DG, DH, DJ, DK, DL, DM, DN, DO, DP, DQ, DR, DT, DU,
DV, DW, DX, DY, DZ.....................................................................................................................31
4.7 Heater Element Wiring..............................................................................................................33
Models: HN, HR, HW, HX, HY, HZ, MT .......................................................................................33
Section 5 –Eurotherm Controller (3000 Series) ............................ 34
5.1 Operation....................................................................................................................................34
Home List Navigation.......................................................................................................................34
Keys..................................................................................................................................................35
5.2 Automatic Tuning......................................................................................................................35
5.3 Troubleshooting.........................................................................................................................37
5.4 Alarm Indicators ........................................................................................................................37
To Acknowledge an Alarm...............................................................................................................37
5.6 Restarting the Automatic Air Purge Timer (After Start-Up).....................................................39
5.7 Manual Air Purge Operation (After Start-Up)...........................................................................39
5.8 Remote Set Point and Retransmission “Scaling”.......................................................................39
Section 6 –Options .................................................................. 40
6.1 Pressure Regulator .....................................................................................................................40
Exploded View Drawing ..................................................................................................................40
Maintenance Instructions..................................................................................................................40
Adjustment........................................................................................................................................40
6.2 Instruction for Initial Start-Up of Non-Pressurized Supply Tank..............................................41
6.3 Instructions for Initial Start-Up of Pressurized Supply Tank ....................................................41
6.4 System “Z” Purge Instructions for All Systems ........................................................................42
6.5 NPS Option................................................................................................................................43
Water Connections............................................................................................................................43
Unit Operation ..................................................................................................................................43
Initial Starting Procedure..................................................................................................................43
Adjusting the Vacuum......................................................................................................................44
6.6 Operation of Automatic Process (Mold) Purge .........................................................................44
6.7 Cool Down and Automatic Shut Off .........................................................................................45
Adjusting Auto Cool Down/Shutdown Timer..................................................................................45
6.8 Emergency Stop.........................................................................................................................45
6.9 Valved Process Bypass ..............................................................................................................45

iii
Section 7 –Troubleshooting Guide .............................................. 46
Section 8 –Condensed Parts List ................................................ 49
8.1 All Models: ................................................................................................................................49
8.2 Duratherm Models:....................................................................................................................49
8.3 Minitherm Models: ....................................................................................................................50
8.4 Hydrotherm II Models:..............................................................................................................50
Section 9 –Model Codes ........................................................... 51
9.1 Duratherm Model Codes............................................................................................................52
9.2 Minitherm Model Codes............................................................................................................53
9.3 Hydrotherm II Model Codes......................................................................................................54
Section 10 –Warranty .............................................................. 55

Water Systems
Quick Start-Up Checklist
2150 Elmwood Avenue, Buffalo, NY 14207
Ph. 716-876-9951; Fax [phone]
www.mokon.com MOKCLST7000 2/15
Please verify that the product received matches the product ordered and that the
equipment is designed for the intended application. The following quick checklist is
an abridged version - always refer to the Mokon Manual provided for additional data
and requirements prior to the commissioning of the unit.
Electrical Inspection
Verify amp draws and voltage on serial tag match electrical service being
supplied.
All electrical termination points checked for tightness.
Electrical wiring completed and disconnect sized and installed per code and
compliance.
Motor rotation verified, motor(s) bumped.
Verify any remote control wiring is complete.
Mechanical Inspection
Mechanical fittings tight.
Unions tight.
Compression fittings tight.
Insure Supply, Drain and Process connections are connected properly and
operating pressure does not exceed ratings.
Location and Good Standard Installation Practices
Confirm safe access to equipment for maintenance, removal and lockout- tag
out.
Insure equipment is designed for the installed environment.
Allow a minimum of 4 feet (1.2 meters) on all four (4) sides to allow for
proper maintenance and operation.
Allow a minimum of 4 feet (1.2 meters) or more above unit for proper
ventilation. Please use extreme caution when dealing with hot surfaces.

1
Section 1 –Warnings and Cautions
Please read and understand this section before operating the system!
1.1 Electrical Warning
The Mokon temperature control system, as with all high voltage electrical equipment, should be
connected according to all local and national codes. All installation, maintenance, service, repair,
adjustment, and operation should be done only by qualified trained electrical personnel who have
read and completely understood this instruction manual. To the upper right is a symbol for
ELECTRICAL DANGER. When it is seen on the following pages of this manual as well as on the
system, care should be taken to avoid possible electric shock. All maintenance and service should
be performed with the power isolated and locked out except where noted.
1.2 Hot Fluid Warning
Exercise EXTREME CAUTION while working on or in the area of the Mokon temperature control
system. The high temperature of the fluid will cause the process lines, the system components, and
the metal cabinetry to become VERY HOT and therefore should NOT be touched. To the upper
right is a symbol for SURFACE MAY BE HOT, HIGH TEMPERATURE. When it is seen on the
following pages of this manual, care should be taken to avoid possible burns. All maintenance and
service must be performed with the system completely cooled. It is advisable to plug the process
ports of any unused zones so that if a wrong button is pressed, fluid will not be pumped through
them.
1.3 Cold Weather Caution
If the Mokon temperature control system will be moved from your plant and will be subjected to
freezing temperatures, the water in the system must be completely drained and/or sufficient
antifreeze added to prevent serious water damage from freezing.
1.4 Excessive Supply Pressure Caution
Model: DN, DO, DP, DQ, DR, DT, DU, DV, DW, DX, DY, DZ, HN, HR,
HW, HX, HY, HZ, MT
Mokon suggests an optional pressure regulator on Mokon temperature control systems for
applications with high supply water pressure (exceeding 50 PSI, 345 kPa) to reduce or eliminate
the potential for water hammer. Recommended pressure is 30 PSI (207 kPa). Water hammer in the
Mokon temperature control system or the process and cooling lines can lead to system damage and
reduced system life. If a pressure regulator is added to the Mokon temperature control system, it
must be of the design that incorporates a bleed off for thermal expansion of the fluid.

2
1.5 Excessive Supply Pressure Caution
Models: DA, DB, DC, DD, DE, DF, DG, DH, DJ, DK, DL, DM
A water supply of 60 PSI (414 kPa) is required to operate these systems at 300oF (149oC). Mokon
suggests an optional pressure regulator on Mokon temperature control systems for applications
with high supply water pressure (exceeding 75 PSI/ 517 kPa) to reduce or eliminate the potential
for water hammer. Water hammer in the Mokon temperature control system or the process and
cooling lines can lead to system damage and reduced system life. If a pressure regulator is added
to the Mokon temperature control system, it must be of the design that incorporates a bleed off for
thermal expansion of the fluid.
1.6 Overhead Piping Warning
When overhead piping is connected to a Mokon temperature control system equipped with an open
reservoir or non-pressurized expansion tank there is risk of overflow of the system’s reservoir tank
upon shutdown, this is due to the back flow of fluid volume from the overhead piping system.
To prevent reservoir tank overflow an overhead piping kit should be installed. This kit is available
from Mokon as an option.
1.7 Short Circuit Current Rating Caution
Equipment supplied with a safety door disconnect is design rated for a short circuit current rating
(SCCR) of 5,000 amperes RMS if protected with a class "RK5" fuse and, equipment supplied with a
power cord is design rated for a short circuit current rating (SCCR) of 10,000 amperes RMS if
protected with a class "J" fuse.
1.8 No Flow Warning
It should be noted that if any external valves are installed in the process flow path, they must be
opened before starting the Mokon temperature control system or risk causing serious damage to
the system and the process.
Fluid must be established (flowing) through the Mokon temperature control system in order for the
safety features to work properly and adequately protect the Mokon temperature control system.
The use of valves downstream of the Mokon temperature control system are not recommended as
they could potentially render the system safeties inoperative if closed. This could cause serious
system damage and would void the warranty. To avoid disabling the standard safety features,
please contact Mokon to discuss optional safety features that may be required to adequately
protect the assembly.
1.9 Non-Potable Water System
This system has been designed for use in non-potable water applications only. For applications
requiring potable water use please contact Mokon directly to discuss a product offering.

3
Section 2 –Installation
2.1 Unpacking
Upon arrival inspection should be done to assure there was no damage during shipping. In
addition, all electrical and mechanical connections should be inspected to ensure that they are
secure and tight. This includes all electrical terminations, mechanical fitting union bulbs,
compression fittings, etc.
Note: Refer to Section 4.1 Maintenance and service.
The maximum weights of the Mokon water systems when drained of water are:
Duratherm - 475 lbs (160 kg)
Dual Zone Duratherm - 950 lbs (232 kg)
Hydrotherm II - 175 lbs (80 kg)
Minitherm - 110 lbs (50 kg)
Properly rated equipment should be used to move this machinery.
When removing system from pallet, lift from bottom only. Care should be taken to ensure that the
system will not tip. After removing from pallet, the system should only be placed on a level
surface.
2.2 Location
Mokon systems should be located in an area that provides adequate space for pedestrian and
vehicle traffic. If this is not feasible, owner should provide additional safeguards including safety
signs.
For optimum system performance, allow adequate space and ventilation around entire system, as
well as a means to direct vapors away from work area.
There should be a minimum of four (4) feet of clearance around the entire Mokon system (all
sides) for adequate ventilation and operation of the system.
If braking casters are included, they must be in the locked position when system is in the operating
position. Prior to moving, unlock the casters.
Customer supplied and installed air vents (mechanical or electrical) should be placed at the highest
point in the process for application where the process height is greater than eight (8) feet above
Mokon system.

4
2.3 Warnings
Owner should ensure by adequate supervision that correct safety, installation, maintenance and
operating procedures described in this manual, as well as recognized industry practice, are followed
by all personnel.
All panels must be in place during normal operation.
The top of the machinery should not be used for storage.
Power sources or energy types referred to in this manual are water and electricity.
This machinery is not for use in hazardous or explosion proof environments.
Under normal operating conditions, the decibel level of the machinery is 67 db or lower.
Any alteration, additions or modifications to any part of the system must receive prior written
approval from Mokon’s Engineering or Customer Service Departments.
Refer to serial tag for motor and heater electrical information and schematic drawing number.
2.4 Electrical Connections
Warning: The Mokon temperature control system, as with all high voltage
electrical equipment, should be connected according to all applicable state
and local codes. All installation, maintenance, service, repair, adjustment,
and operation should be done only by qualified trained electrical
personnel who have read and completely understood this instruction
manual.
Before operating the Mokon temperature control system, the grounding
wire must be connected. The grounding wire is the green or green and
yellow wire connected to the frame of the system.
Connect ground wire to the ground screw (labeled PE or GND) located in the electrical box. Connect
power lines L1, L2, L3, to disconnect switch or terminal blocks marked L1, L2, and L3 respectively,
inside the electrical box. Overcurrent protection of the supply conductors should be sized according
to The National Electrical Code (NEC) and any other applicable state and local codes.

5
2.5 Water Connections
Exercise extreme caution while working on or in the area of the Mokon
temperature control system. The high temperature of the fluid will cause
the process lines, the system components, and the metal cabinetry to
become very hot and therefore, they should not be touched.
There are four (4) convenient and clearly marked connections, "Supply Water," "To Process,"
"From Process" and "Drain Water."
Note: It is not recommended that quick disconnects be used on any of the connections, as they
will restrict the flow.)
Caution: The “Supply Water” fluid connection must not be valved in any
way. If you add or replace a pressure regulator to a Mokon temperature
control system it must be of the design that incorporates a bleed off for
thermal expansion of the fluid. This style of regulator is available from
Mokon. During a heating cycle, thermal expansion is created and is bled
off through the supply. If the supply source is valved or restricted in any
way, this will cause the Mokon temperature control system to lose it’s
capabilities of bleeding off for thermal expansion, and can damage the
system. Consult the Mokon factory for recommendations.
Supply Water: Connect this port to an adequate source of cold, clean supply water. Do not restrict
incoming water to the Mokon temperature control system for the reasons outlined above. The
pressure regulator (if included on system as an option) is set at the factory for suitable operation of
the Mokon temperature control. For systems with a pressure regulator, see Section 6.1 for
adjustment procedures. For systems without a pressure regulator see Section 1.4 or 1.5 for
recommended pressures.
To Process: Connect this port to the process inlet, through which temperature controlled water will
enter the process. Use full size unrestricted high temperature hose or pipe rated for the proper
pressure and temperature.
From Process: Connect this port to the process outlet, from which temperature controlled water will
leave the process. Use full size unrestricted high temperature hose or pipe rated for the proper
pressure and temperature.
Caution: The “Drain Water” connection must not be valved in any way. In
plant recirculating systems return line pressure restrict the performance
of open circuit type Mokon temperature control systems. If plant drainage
systems are pressurized it can cause the Mokon temperature control
system to reduce or lose its cooling capabilities. Consult the Mokon
factory for recommendations.
Drain Water: Connect this port to drain (or return line in an in plant closed recirculation system).
Reservoir Filling: For Mokon temperature control systems with an optional fluid reservoir, the
reservoir needs to be filled prior to operation. Fill to a minimum of 1/2 full with a water or
water/glycol mixture.

6
Section 3 –Operation
3.1 Initial Starting Procedure
Turn on the water supply connected to the Mokon temperature control system. (See Section
2.5 for water connections)
Turn on the electrical main disconnect switch. (See Section 2.4 for electrical connections)
If provided, turn on the electrical box door disconnect switch.
For each zone, check the motor rotation by turning on the system momentarily (press the
“Start” button then the “Stop” button). As the pump slows down, check the motor rotation.
If the motor is not rotating in the direction of the arrow label located on the motor housing
(clockwise from the lead end), reverse any two power cord leads to change the direction of
the motor rotation. (See Section 2.4)
Restart the system and set the controller to the minimum temperature. (See Section 5 for
controller instructions)
Allow the system to run for several minutes with the controller set to the minimum
temperature to remove air from the system. All systems have as standard an auto-air
purge, factory default set for 5 minutes. After 5 minutes of operation at the minimum
temperature the system should automatically purge itself of air. There is also a manual
purge button that can be used on Duratherm and Minitherm systems for Hydrotherm II
systems refer to Section 5.5 and 5.6 for additional air purge instructions.
Note: Some processes require a different air purge timed cycle other than the factory
default set value. Adjustments can be made to either lengthen or shorten this timed cycle.
Please refer to Sections 5.5 and 5.6 for additional information on the automatic air purge
feature.
Set the controller to the desired temperature. The system will reach the setpoint
temperature. (See Section 5 for controller instructions)
Note: Automatic air purge, during start-up removes air from lines (add an air-bleed and/or
air separator at highest process loop point if needed to help expel air from process).
3.2 Process Flow Adjustment
The operator must determine and set proper water flow rate for the most efficient and
trouble free operation.
oWater flow rate through the process is determined by the pressure losses in the
process loop. Generally, higher flow rates result in turbulent flow achieving
maximum temperature control and lower maintenance.
oIf the flow rate exceeds the motor HP capacity, the electric motor will draw excessive
amps. This is a result of the process loop’s ability to flow water at a greater rate than
can be provided by the pump. This will eventually result in tripping the thermal
motor overload relay (overload relays open and the unit will shut down)
If an excessive flow situation is encountered and the motor overload circuit has tripped, the
operator must manually reset the overload relay before operations can continue. This is
done by opening the electrical panel cover, identifying the reset level of the overload relay,
and pushing the reset level “in” until the overloads are reset.
If a motor overload situation persists, the operator must adjust the flow rate to match the
system pressure loss (reduce flow rate) to prevent continual tripping of the overload relay.

7
oOpen electrical cabinet panel door. Note: That the electrical power is engaged
at this point and caution must be observed while the cabinet panel is open.
oIdentify the motor starter block. This block consists of the motor starter contactor
and the overload relay.
oPlace an amp meter on a single power lead coming from the overload relay.
oLocate the motor name plate on the pump motor housing. The full load amp rating
for the motor is listed on the name plate.
oEngage the electrical power supply and start the unit.
oThe amp meter will display the motor amps. Compare the actual motor amps as
displayed on the amp meter to the full load amp rating as listed on the motor name
plate.
oIf the amp draw is excessive (higher than the listed name plate amp rating), a
throttling valve must be installed in the “from process” water line. The throttling
valve can be a gate valve or a ball valve.
oWith the throttling valve installed, fully close the valve and then engage the pump
motor. Slowly open the throttling valve and monitor the motor amps as displayed on
the amp meter until the actual motor amps equal the listed full load amp rating of
the motor. The process flow is correctly adjusted. The valve should remain in this
position during operation.
3.3 Changing Temperature Settings
If a new temperature setting is required while the system is in operation, adjust the controller to
the new desired setpoint temperature. See Section 5 for controller instructions.
3.4 Shut Down Procedure
Cool the Mokon temperature control system down by reducing the setpoint temperature to 100oF
(38oC) or lower. When the system is cooled, push the "Stop" button to shut off the system. DO
NOT SHUT THE SYSTEM OFF AT ELEVATED TEMPERATURES, THIS CAN BE DETRIMENTAL
TO SYSTEM LIFE. The water and main electrical power to the Mokon temperature control system
may be turned off if desired but is not necessary unless the system is being relocated or for
prolonged shut down.
3.5 Restarting Procedure
If the water lines and main electrical power have not been disconnected, refer to Section
3.1.
If the water lines and/or the main electrical power have been disconnected, refer to Section
2.4 for Electrical Connections, Section 2.5 for Water Connections, and Section 3.1 for Initial
Start-Up Procedure.

8
Section 4 –Maintenance and Service
Warning: The maintenance and service procedures included in Sections
4.1 –4.11 require that all power sources to the Mokon temperature
control system be shut off, isolated and locked out (exceptions noted) and
that the system be completely cooled. Follow all local and national codes
and procedures for working on electrical equipment. Failure to do so could
result in injury or death. Only qualified electrical personnel should install,
maintain, repair, adjust, and operate Mokon temperature control systems.
The instruction manual furnished with the system should be completely
read and understood before system maintenance.
The following hazard warning symbols will be used to denote a specific
hazard associated with a procedure.
Electrical Danger
High Temperature
Surface May Be Hot
High Voltage &
Hot Surface
4.1 Preventative Maintenance
Mokon temperature control systems are designed for a long, trouble free service life under a
variety of conditions, with a minimum of maintenance. Performing the following preventative
procedures will extend the life of your system. Refer to Section 4.1 - 4.11 in the instruction manual
for specific adjustment or service procedures. Refer to the condensed parts list included in Section
8 of the instruction manual for proper replacement parts if required.
The preventative maintenance section is broken into weekly, monthly, and every three months
checks. Associated with each check is a series of corrective procedures that may solve a problem
detected in the check. If the corrective procedures do not resolve a problem detected in the check,
see the trouble shooting guide in Section 7 for a complete list of corrective measures.

9
Electrical Preventative Maintenance
Weekly Checks
Corrective Procedures
Check electrical box interior components
for any discoloration, or any burn marks
Correct component wiring
Verify voltage and frequency stamped on
system matches customer supply voltage
and frequency
Correct excessive system load (current
draw)
Verify customer supply voltage is balanced
and fluctuations are within 15% of nominal
Verify wire gauge for main power hookup
is properly sized
Replace components if needed
Check for blown fuses
Replace with the correct size and style fuse
For units with solid state contactors,
inspect the screen covering the fan inside
the electrical enclosure
If clogged with debris, clean or replace the
screen. If not cleaned or replaced
excessive heat build-up can occur in the
electrical enclosure reducing component
life and wiring. System warranty will be
void.
Monthly Checks
Corrective Procedures
Check that the high temperature switch
(TS) has a set of N.O. and N.C. contacts,
and it is properly wired
Replace the switch if necessary
Check that the low pressure switch (PS)
has a set of N.O. and N.C. contacts, and it
is properly wired
Replace the switch if necessary
Every 3 Months Checks
Corrective Procedures
Check that the interior electrical and
mechanical components are securely
fastened to the back panel, and/or to the
sides of the electrical box
Tighten with proper tooling
Check that the ratings of overload
protection (such as fuses and circuit
breakers) adequately protect the line's
maximum current carrying capacity
Inspect/replace fuses
Inspect/replace motor starter overloads
Check the fuses against the electrical
schematic for proper size according to the
systems voltage
Replace if different
Slightly tug on each wire / conductor to
make sure it makes a solid contact to its
attached component. Pay close attention to
the green grounding wires.
Tighten with proper tooling

10
Pump/Motor and Mechanical Connections Preventative Maintenance
Weekly Checks
Corrective Procedures
Check for foreign materials obstructing
airflow in the motor and pump area
Remove all dust, lint, grease or oil with a
cloth and/or brush
Check the motor rotation is correct by
observing the direction of rotation through
the grillwork on the motor (Power On then
Off)
Reverse any two incoming power cord
leads to correct rotation
Monthly Checks
Corrective Procedures
Check that all bolts and screws are
securely tightened
Tighten with proper tooling
Check for plumbing leaks
Repair solder joints
Replace necessary parts if leaks persist
Visually check all threaded fittings for signs
of leakage
Tighten with proper tooling
Replace necessary parts if leaks persist
Check that the motor current draw
matches the serial tag rating
Correct motor wiring
Verify supply voltage is balanced and
fluctuations are within 15% of nominal
Check gauge readings on the cabinet
(Power On)
Verify suction or discharged line not
partially clogged
Verify no restrictions in process or supply
lines
Replace gauge(s) if needed
Semi Annual Checks
Corrective Procedures
Check that all threaded fittings within the
fluid loop are securely tightened
Tighten with proper tooling
Replace necessary parts if leaks persist

11
Miscellaneous Preventative Maintenance
Monthly Checks
Corrective Procedures
Check that all applicable lights, gauges,
and optional indicators are functioning
properly
(Power On)
Replace necessary components
Check the cooling solenoid operation by
elevating setpoint temperature manually.
While in the heating mode, push the
manual air purge button. Listen for the
cooling solenoid's audible energizing and
de-energizing "clicking sound." Observe
process temperature decreasing. (Power
On)
Using a Voltmeter, determine if solenoid
coil is energizing
Replace solenoid valve, if necessary
Check the controller calibration by setting
the controller for three random setpoints
within the operating range of the system.
Observe that the process temperature
output is within the accuracy of the
controller. (Power On)
Calibrate controller using Section 5 in the
instruction manual (Power On)
Verify the thermocouple wires at controller
are secure
If controller does not respond to any of the
above steps, consult the Mokon factory
Do not attempt repairs as the
warranty could become void.
Check the system for leaks at operating
temperatures. As the system reaches the
setpoint temperature, visually check for
leaks.
Repair leaks and/or tighten fittings
Replace necessary parts

12
Monthly Checks
Corrective Procedures
Check that the heater current draw
matches the serial tag rating
Verify heater wiring stake-on is secured
Correct heater wiring
Verify customer supply voltage is balanced
and fluctuations are within 15% of nominal
Replace elements if necessary
Check that the "Warning," "High Voltage,"
"Caution," and lamicoid labeling are
adhering to the correct locations
Replace torn, damaged or missing labels
Check screen in optional pressure regulator
for debris
Remove screen and clean

13
4.2 Pump Maintenance
Models: DN, DO, DR, DT, DU, DW, DY, DZ, HN, HR, HW, HX, HY, HZ
Exploded View Drawing Models: DN, DO, DR, DT, DU, DW, DY, DZ
REF.
NO.
QTY.
DN
3
HP
DO
5
HP
DR
1.5
HP
DT
¾
HP
DU
5
HP
DW
3
HP
DY
1.5
HP
DZ
¾
HP
DESCRIPTION
PART #
1
1
CASE 1.25 x
1 NPT
018266
1






CASE 1.25 X
1 NPT
018268
1


CASE 1.5 x
1.25 NPT
018267
2
1


IMPELLER
4.88”,
STAINLESS
018275
1


IMPELLER
5.25”,
STAINLESS
018276
1


IMPELLER
6.3”,
STAINLESS
018277
1


IMPELLER
6.3”,
STAINLESS
018342
4
1








MOTOR 56J
CONSULT
FACTORY
11
1








COVER,
STAINLESS
018269
24*
1








NUT
018270
30*
1








D-WASHER
018271
40*
1








FLINGER
018272
71
1








DISC IRON
018273
73*
1








GASKET,
CASE
018274
89*
1








SEAL, 5/8”
IN REPAIR
KIT
* - DENOTES COMPONENTS INCLUDED IN REPAIR KIT 018246.

14
Exploded View Drawing Models: HN, HR, HW, HX, HY, HZ
REF.
NO.
QTY.
HN
3.0
HP
HR
1.5
HP
HW
2.0
HP
HX
1.0
HP
HY
¾
HP
HZ
½
HP
DESCRIPTION
PART #
1
1






CASE 1.25 x 1
NPT
018266
2
1


IMPELLER
4.88”,
STAINLESS
018275
1

IMPELLER 4.0”,
STAINLESS
018498
1


IMPELLER
5.75”,
STAINLESS
018497
1

IMPELLER 6.3”,
STAINLESS
018277
1
IMPELLER 6.3”
STAINLESS
018342
4
1






MOTOR 56J
CONSULT
FACTORY
11
1






COVER,
STAINLESS
018269
24*
1






NUT
018270
30*
1






D-WASHER
018271
40*
1






FLINGER
018272
71
1






DISC IRON
018273
73*
1






GASKET, CASE
018274
89*
1






SEAL, 5/8
IN REPAIR
KIT
* - DENOTES COMPONENTS INCLUDED IN REPAIR KIT 018246.

15
Seal Replacement/Maintenance
Warning: Make certain that the system is disconnected from the power
source in compliance with all local and national codes before attempting
to service or remove any components. Never run the pump when dry.
Maintenance:
Inspection: Pump should be periodically checked for proper operation. If the system has changed
or if the pump is operating noisily or erratically, then the pump should be removed and examined.
It should be repaired and parts replaced as necessary.
Cleaning: Remove oil, dust, dirt, water, chemicals from exterior of pump and motor. Blow out
interior of open motors with clean compressed air at low pressure. Regularly drain moisture from
TEFC motors.
Draining: If the pump is located in an area subject to freezing temperatures, the pump must be
drained when not in operation or add sufficient antifreeze.
Seal Replacement:
Disassembly:
Turn off power.
Close suction and discharge valves (if equipped).
Drain pump.
Remove bolts holding base to foundation.
Remove casing bolts.
Remove motor and rotating element from casing, leaving casing and piping undisturbed, if
possible. If not, then remove the whole assembly.
Insert a screwdriver in one of the impeller waterway passages and back off the impeller nut
(Ref 24).
Remove motor shaft end cap. Insert a screwdriver in slot of motor shaft. While holding shaft
against rotation, unscrew impeller (Ref 2) from shaft by turning counterclockwise when
facing impeller.
Pry off rotating member of mechanical seal from motor shaft by using two (2) screwdrivers.
Be careful not to damage the pump cover (Ref 11).
Remove pump cover (Ref 11 & 71) from cast iron disc. (There is no hardware used to attach
cover to disc.) Place cover on a flat surface with convex side down. Push out stationary
member of mechanical seal. It is not necessary to remove the cast iron disc from the motor
to replace the seal.