Graco THERM-O-FLOW T7 Series User manual

Graco Inc. P.O. Box 1441 Minneapolis, MN 55440-1441
Copyright 2004, Graco Inc. is registered to I.S. EN ISO 9001
309832D
Instructions
THERM-O-FLOW®
Hot Melt Tank T7
For melting and pumping non-explosive hot melt thermoplastic
adhesives. Not recommended for water-based curable or
solvent-based adhesive.
Model 234251
115 VAC
Model 234252
230 VAC
300 psi (2.0 MPa, 20.6 bar) Maximum Working Pressure
Important Safety Instructions.
Read all warnings and instructions in this
manual. Save these instructions.
See page 2 for table of contents.

Manual Conventions
2309832D
Contents
Manual Conventions . . . . . . . . . . . . . . . . . . . . . . . . 2
Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Melt unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Front panel display . . . . . . . . . . . . . . . . . . . . . . . 7
Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Mounting hot melt tank . . . . . . . . . . . . . . . . . . . 10
Connecting hose . . . . . . . . . . . . . . . . . . . . . . . . 11
Connecting applicator . . . . . . . . . . . . . . . . . . . . 12
Connecting timers and controllers . . . . . . . . . . 12
Adding material to tank . . . . . . . . . . . . . . . . . . . 13
Electrical wiring . . . . . . . . . . . . . . . . . . . . . . . . . 13
Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Pressure relief procedure . . . . . . . . . . . . . . . . . 14
Flushing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Starting the hot melt system . . . . . . . . . . . . . . . 15
Adjusting panel controls . . . . . . . . . . . . . . . . . . 15
Dispensing material . . . . . . . . . . . . . . . . . . . . . 18
Adjusting timers and controllers . . . . . . . . . . . . 18
Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Daily Maintenance . . . . . . . . . . . . . . . . . . . . . . 19
Tank Screen Inspection . . . . . . . . . . . . . . . . . . . 19
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Tools Used . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Replacing hose . . . . . . . . . . . . . . . . . . . . . . . . . 23
Replacing front panel . . . . . . . . . . . . . . . . . . . . . 25
Replacing front panel fuses . . . . . . . . . . . . . . . . 26
Removing tank cover . . . . . . . . . . . . . . . . . . . . . 26
Replacing motor . . . . . . . . . . . . . . . . . . . . . . . . 27
Replacing coupling assembly . . . . . . . . . . . . . . 28
Replacing pump . . . . . . . . . . . . . . . . . . . . . . . . . 29
Replacing pressure adjuster . . . . . . . . . . . . . . . 31
Replacing fluid outlet fittings . . . . . . . . . . . . . . . 33
Replacing motor control board fuse 118321 . . . 33
Replacing over temperature switch assembly . . 34
Replacing tank heaters and thermistor assembly 35
Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Housing assembly . . . . . . . . . . . . . . . . . . . . . . . 36
Motor, pump to frame and tank assembly . . . . . 38
Tank assembly . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Pump and pressure adjuster assembly . . . . . . . 42
Schematics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Front panel harness . . . . . . . . . . . . . . . . . . . . . . 44
Base harness . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Base wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Technical Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Graco Standard Warranty . . . . . . . . . . . . . . . . . . . 50
Graco Information . . . . . . . . . . . . . . . . . . . . . . . . . 50
Manual Conventions
Note
WARNING
WARNING: a potentially hazardous situation which, if
not avoided, could result in death or serious injury.
Warnings in the instructions usually include a symbol
indicating the hazard. Read the general Warnings
section for additional safety information.
CAUTION
CAUTION: a potentially hazardous situation which, if
not avoided, may result in property damage or
destruction of equipment.
Additional helpful information.

Warnings
309832D 3
Warnings
The following warnings include general safety information for this equipment. More specific warnings are included in
the text where applicable.
WARNING
ELECTRIC SHOCK HAZARD
Improper grounding, setup, or usage of the system can cause electric shock.
• Turn off and disconnect power cord before servicing equipment.
• Use only grounded electrical outlets.
• Use only 3-wire extension cords.
• Ensure ground prongs are intact on sprayer and extension cords.
PRESSURIZED EQUIPMENT HAZARD
Fluid from the gun/dispense valve, leaks, or ruptured components can splash in the eyes or on skin and
cause serious injury.
• Follow Pressure Relief Procedure in this manual, when you stop spraying and before cleaning,
checking, or servicing equipment.
• Tighten all fluid connections before operating the equipment.
• Check hoses, tubes, and couplings daily. Replace worn or damaged parts immediately.
EQUIPMENT MISUSE HAZARD
Misuse can cause death or serious injury.
• Do not exceed the maximum working pressure or temperature rating of the lowest rated system
component. See Technical Data in all equipment manuals.
• Use fluids and solvents that are compatible with equipment wetted parts. See Technical Data in all
equipment manuals. Read fluid and solvent manufacturer’s warnings.
• Check equipment daily. Repair or replace worn or damaged parts immediately.
• Do not alter or modify equipment.
• For professional use only.
• Use equipment only for its intended purpose. Call your Graco distributor for information.
• Route hoses and cables away from traffic areas, sharp edges, moving parts, and hot surfaces.
• Do not use hoses to pull equipment.
• Comply with all applicable safety regulations.
PRESSURIZED ALUMINUM PARTS HAZARD
Do not use 1,1,1-trichloroethane, methylene chloride, other halogenated hydrocarbon solvents or fluids
containing such solvents in pressurized aluminum equipment. Such use can cause serious chemical
reaction and equipment rupture, and result in death, serious injury, and property damage.
BURN HAZARD
Equipment surfaces and fluid that’s heated can become very hot during operation. To avoid severe
burns, do not touch hot fluid or equipment. Wait until equipment/fluid has cooled completely.
PERSONAL PROTECTIVE EQUIPMENT
You must wear appropriate protective equipment when operating, servicing, or when in the operating
area of the equipment to help protect you from serious injury, including eye injury, inhalation of toxic
fumes, burns, and hearing loss. This equipment includes but is not limited to:
• Protective eyewear
• Clothing and respirator as recommended by the fluid and solvent manufacturer
•Gloves
• Hearing protection

Installation
4309832D
Installation
THERM-O-FLOW®T7 Hot Melt System is used for melt-
ing and pumping hot melt thermoplastic adhesives. The
system consists of the melt unit, up to two heated supply
hoses, and applicator. System operation is further
enhanced by the use of pattern controllers, timers, foot
switches, or other such devices. All temperatures in the
hot melt system are controlled by closed loop electron-
ics using thermistor-based sensors.
Melt unit
Includes heated melt tank with a motor-driven, positive
displacement gear pump. Front panel controls tempera-
tures and settings. Fluid pressure is supplied by the reg-
ulator that controls flow through a bypass mechanism.
Pump and Motor
To prevent damage to the pump and/or motor with mate-
rial that is too viscous or solid, operation of the pump
motor is inhibited until the tank reaches approximately
90% of the selected temperature. The pump and motor
are protected by a fuse that blows if a stall or overload
condition occurs. See Repair starting on page 23, for
replacement instructions.
Auxiliary Input Connection
One auxiliary connection is available for each
hose/applicator employed in the system. Foot switches,
timers, and air pattern controllers connect to the auxil-
iary input.
On/Off Switch and Circuit Breaker
The on/off switch and circuit breaker (R) is a manual cir-
cuit breaker and also a magnetic breaker. See FIG. 4,
page 10.The magnetic breaker opens the circuit when
the current exceeds 20 amps (at 115 VAC or 230 VAC)
or when over-temperature conditions are sensed at the
melt tank. See Troubleshooting, page 20.
FIG. 1: Tank Dispensing Material

Installation
309832D 5
Accessories
Install the following accessories shown in FIG. 2, using
adapters as necessary.
Hoses
•Heated Hose (J): allows adhesive to flow from the
tank to the applicator while maintaining the set tem-
perature. Can install up to two hoses:
• Extrusion Hose: for extrusion application
• Spray/Swirl Hose: includes air line in the hose
jacket.
Applicators
See manual applicator instructions (310801) or auto-
matic applicator instructions (310803) for specific
instruction on how to install applicators to the hot melt
tank.
•EG Electric Head (D): for automatic dispensing. No
air needed for application. Use with timer and pat-
tern controller.
•COM-PAK Pneumatic (H): for automatic dispens-
ing. Use with timer and pattern controller.
•AG Applicator (F): for automatic dispensing. Use
with timer and pattern contoller. Air-open, air-close
with spring-assist closing action.
•HG Handgun (G): for manual dispensing. Top or
bottom feed available. Control pump motor with reed
relay switch on the gun.
•Vertical Electric Applicator (VEA) (E): for manual
dispensing. One or two hand control options.
Timers and controllers
See EC-20/40 timer manual 310814 for instruction.
•EC-20 (B): 2- event pattern timer for automatic
application.
•EC-40 (B): 4-event pattern timer for automatic appli-
cation.
•Air Saver Control Unit (C): for spray or swirl pat-
tern applications. Adjusts and regulates air to the
applicator.
Hose Part
No.
Extrusion,
Spray/Swirl
Application
Length VAC
117852 Extrusion 4 ft (1.2 m) 115
117853 Extrusion 6 ft (1.8 m) 115
117854 Extrusion 8 ft (2.4 m) 115
117855 Extrusion 10 ft (3 m) 115
117856 Extrusion 12 ft (3.6 m) 115
117857 Extrusion 16 ft (4.8 m) 115
117858 Extrusion 18 ft (5.4 m) 115
117859 Extrusion 24 ft (7.3 m) 115
117860 Extrusion 4 ft (1.2 m) 230
117861 Extrusion 6 ft (1.8 m) 230
117862 Extrusion 8 ft (2.4 m) 230
117863 Extrusion 10 ft (3 m) 230
117864 Extrusion 12 ft (3.6 m) 230
117865 Extrusion 16 ft (4.8 m) 230
117866 Extrusion 18 ft (5.4 m) 230
117867 Extrusion 20 ft (6 m) 230
117868 Extrusion 24 ft (7.3 m) 230
117872 Swirl/Spray 4 ft (1.2 m) 115
117873 Swirl/Spray 6 ft (1.8 m) 115
117874 Swirl/Spray 8 ft (2.4 m) 115
117875 Swirl/Spray 10 ft (3 m) 115
117876 Swirl/Spray 12 ft (3.6 m) 115
117877 Swirl/Spray 16 ft (4.8 m) 115
117878 Swirl/Spray 18 ft (5.4 m) 115
117879 Swirl/Spray 24 ft (7.3 m) 115
117880 Swirl/Spray 4 ft (1.2 m) 230
117881 Swirl/Spray 6 ft (1.8 m) 230
117882 Swirl/Spray 8 ft (2.4 m) 230
117883 Swirl/Spray 10 ft (3 m) 230
117884 Swirl/Spray 12 ft (3.6 m) 230
117885 Swirl/Spray 16 ft (4.8 m) 230
117886 Swirl/Spray 18 ft (5.4 m) 230
117887 Swirl/Spray 24 ft (7.3 m) 230
Hose Part
No.
Extrusion,
Spray/Swirl
Application
Length VAC

Installation
6309832D
Key:
A T7 Hot Melt Tank
B Timer (required for automatic application)
C Air Controller (required for airspray and swirl application)
D EG Applicator
E VEA Applicator
F AG Applicator
G Handgun Applicator
H COM-PAK Applicator
J Fluid Hose
K Hose Electrical Connector
L Timer to Tank Power Cord
FIG. 2: Typical Installation
D
F
H
E
G
BA
L
J
K
C

Installation
309832D 7
Front panel display
FIG. 3: Front Panel Display
Loop Select Up
Loop Select Down Pump Function
To g g l e
Loop Select
On/Off
Pump Functions
Actual
Temperature
Over
Temperature
Error
Open
Sensor
Error
Range
Indicator
Pump Status
Pump Speed
Increment-
Decrement
Pump Speed
Pump
Indicator
Standby
On/Off
Status
Standby
Toggle
Set
Temperature
Set Temperature
Increment-
Decrement

Installation
8309832D
Front panel display
See FIG. 3.
Control Name Function
Loop Select Up/Down Selects device for modification. Lights to the left of device
signify the device is ready to be modified. Enables temper-
ature Range Digit LED and Actual Temperature LED.
Set Temperature
Increment/Decrement
Selects the temperature range digit and set point tempera-
ture.
Loop Select On/Off Turns specified device settings (auxiliary, hose, head) on
or off. Does not affect the tank zone. Lights to the right of
the device will show if device is on or off. Changes °F or
°C temperature setting.
Pump Function Toggle Selects the pump settings Cycle, Crawl, or Run:
• CYCLE: Pump runs when applicator is actuated.
For automatic application, the pump will run when timer is
activated.
• CRAWL: Pump is at a constant slow turning
velocity, keeping constant pressure from the pump, to the
hose and applicator. When applicator is actuated the
pump switches to cycle setting. When applicator is off the
pump switches back to crawl setting.
• RUN: Pump is always on.
Pump Functions Shows GREEN when ready. Shows RED when the tank is
not ready or the Pump Control is off.
Over Temperature
Error
Flashes RED when over-temperature condition is
detected. The loop indicator LED for the affected zone
flashes RED. Heating is disabled. See Troubleshooting,
page 20.
Open Sensor Error Shows RED when condition is sensed. The affected zone
is automatically de-energized. The loop indicator LED for
the affected zone flashes RED. See Troubleshooting,
page 20.
Actual Temperature Displays actual temperature (°F or °C) for selected zone.

Installation
309832D 9
Range Digit Shows the range currently set for the tank, hose, and head
temperatures. See Temperature Range Chart, page 15.
Pump Status Indicates if pump is on or off. Shows RED if pump is off or
the tank is not ready. Shows GREEN when pump is on.
Pump Speed
Increment/Decrement
Increases or decreases pump speed.
Pump Speed Indicator Shows the current level of pump speed. Lights are
GREEN to show speed level. The more lights are shown,
the faster the pump is running.
Pump Control On/Off Turns pump on or off.
Standby Status Shows GREEN when Standby Toggle is actuated.
Standby Toggle Starts cooling the tank, hoses, and applicators to approxi-
mately 75% of the set point.
Set Temperature
(Standby Timer)
Shows the set temperature (°F or °C) of selected device.
Shows set time that you want the Standby activated.
Control Name Function

Setup
10 309832D
Setup
Mounting hot melt tank
Bolt the hot melt tank securely to appropriate surface.
Bolt holes are provided on the base of the tank. Mount
tank where hose fittings are accessible from the bottom
of the tank with wrenches. Floor mounting stand 118089
is available.
FIG. 4: T7 connections and power supply
Key:
M Auxiliary Bypass Connection
N Power Cord (not shown)
P Fluid Outlet
Q Pressure Adjuster
R On/Off Power Switch
S Hose Electrical Receptacle (shown
underneath cover)
Q
R
S
P
M
N

Setup
309832D 11
Connecting hose
WARNING
To avoid accidental system pressurization or
electrical shock, disconnect power cord and turn
the on/off switch to OFF. See Warnings, page 3.
WARNING
To prevent hose damage, do not flex hose when
cold. When hot, the hoses have a minimum bend
diameter of 16 in. (40.64 cm).
115 VAC tanks can support up to two 16 ft (4.8
m) of total hose. 230 VAC tanks can support up
to two 24 ft (7.3 m) of total hose. Read Warn-
ings, page 3.
WARNING
Wait until equipment/fluid has cooled completely.
See Warnings, page 3.
1. Raise or tilt the melt unit backward to access the
fluid outlet fittings.
2. Connect hose (J) to fluid outlet fitting (P). Tighten
with 11/16 in (mm) opened end wrench.
To prevent leakage, make sure hose is seated
securely on inlet fitting.
To insure proper seating of threads, make sure inlet
threads are clean. See Troubleshooting, page 20.
3. Connect hose electrical connector (K) to hose elec-
trical receptacle (S). Make sure pins align properly.
4. Screw bayonet ring of the plug onto the receptacle.
To connect second hose, repeat steps 1 through 4.
K
J
S
P

Setup
12 309832D
Connecting applicator
See hot melt tank applicator manuals for specific
instruction on how to install applicators to the hot melt
tank.
• 310801 Manual Applicator manual
• 310803 Automatic Applicator manual
Connecting timers and
controllers
See EC-20/40 timer manual 310814 for instruction. See
appropriate applicator manual for air saver control
instructions.
• 310801 Manual Applicator manual
• 310803 Automatic Applicator manual
Pattern controllers supplied by Graco come with termi-
nated cables to simplify connection to the melt system.
A cable with one end unterminated (118243) is available
to allow connection of a customer-supplied controller
into the melt system.

Setup
309832D 13
Adding material to tank Electrical wiring
The hot melt tanks use single phase, 100 to 130 VAC or
200 to 240 VAC, 50 to 60 Hz power sources, each with
earth ground for safety. The 115 VAC tanks come
equipped with a 15 amp molded plug for convenient
connection to a 115 VAC, 20 amp grounded receptacle.
The 230 VAC tanks come with a molded plug for con-
nection to an electrical circuit box or user-supplied plug.
WARNING
This equipment is designed for use with standard
adhesive and sealant such as EVAs, butyls, and
polyolefins with flash points above 450°F
(232°C). Not recommended for water curable or
solvent based adhesive. Do not use flammable
material or material not compatible with the spec-
ifications of this equipment. Failure to follow this
instruction can cause burn injury to operators
and damage to equipment.
1. Make sure melt tank has been flushed and cleaned.
See Flushing page 14.
If material to be added is compatible to existing
material in tank, flushing is not necessary.
2. Fill the melt tank with the amount of adhesive mate-
rial that will be used in one day. Material should not
be higher than 1.5 in. (4 cm) from the top of the
tank.
3. Follow the material manufacturer’s instructions for
operating temperature.

Operation
14 309832D
Operation
Pressure relief procedure
Flushing
WARNING
Follow Pressure relief procedure when you stop
spraying and before cleaning, checking, servicing, or
transporting equipment. Read Warnings, page 3.
1. Shut off pump motor.
2. Actuate applicator, dispensing material into an
empty pail, until material stops dispensing through
the applicator.
WARNING
This equipment is designed for use with standard
adhesive and sealant such as EVAs, butyls, and
polyolefins with flash points above 450°F
(232°C). Not recommended for water curable or
solvent based adhesive. Do not use flammable
material or material not compatible with the spec-
ifications of this equipment. Failure to follow this
instruction can cause injury to operators and
damage to equipment.
• Flush before changing materials.
• Flush at the lowest pressure possible. Check
connectors for leaks and tighten as necessary.
• Flush with purging compound 118090.
1. Make sure material in tank is completely dispensed.
2. Follow Pressure Relief Procedure, page 14.
3. Remove nozzle and clean with compound.
4. From inside tank, pull out tank filter screen 118211.
Clean with purging compound and inspect for dam-
age and replace. See Parts, page 40.
5. Put compound into tank.
6. Start up the hot melt system. Follow instructions for
Starting the hot melt system, page 15; Adjusting
panel controls, page 15; and Dispensing mate-
rial, page 18.
7. Trigger the gun until clean compound dispenses.
8. Turn on/off switch (R) OFF and unplug unit. See
FIG. 4, page 10.
9. Remove gun from hose. See gun manual to further
clean gun.

Operation
309832D 15
Starting the hot melt system
Adjusting panel controls
Refer to the material manufacturer’s specifications for
correct operating temperatures.
Temperature Range Chart
The temperature range chart shows each range number
and its corresponding tank, hose, and applicator tem-
perature range.
Setting temperature to
Fahrenheit (°F) or Celsius (°C)
Selecting tank
Setting temperature range
The temperature range number reflects the setting for
the tank, hose, and applicator. See Temperature
Range Chart, page 15.
1. Plug in hot melt system.
2. Turn on/off switch (R) ON. See FIG. 4, page 10.
Range Tank Temperature
Hose and
Applicator
Temperature
1
120 to 195°F
49 to 91°C
150 to 225°F
66 to 107°C
2
160 to 235°F
71 to 113°C
190 to 265°F
88 to 129°C
3
200 to 275°F
93 to 135°C
230 to 305°F
116 to 152°C
4
240 to 315°F
116 to 157°C
270 to 345°F
132 to 174°C
5
280 to 355°F
138 to 179°C
310 to 385°F
154 to 196°C
6
320 to 395°F
160 to 202°C
350 to 425°F
177 to 218°C
1. Use the loop select up/down to select tank
. The LED to the left of the device should
show GREEN.
2. Once the tank device is selected and LED is
GREEN, press the loop select up four times.
The range indicator digit will begin flashing.
3. Press the loop select on/off . Notice the actual
temperature display . If the temperature
in the display is lower, it is set to °C. If the tempera-
ture in the display is higher, it is set to °F.
Use the loop select up/down to select
tank . The LED to the left of the device indicates
selection.
1. Select the tank and press the loop select up
four times. The range indicator digit will begin
flashing.
2. Press the set temperature increment or decrement
to set appropriate range digit. See Tempera-
ture Range Chart, page 15. This will only raise or
lower the range digit value one level. To change the
value, repeat steps 1 and 2.

Operation
16 309832D
Selecting hoses and applicators
Setting tank, hose, and applicator temperature
Setting pump control and speed
1. Use the loop select up/down to scroll through
and select each device .
2. Press the loop select on/off ON. The LED to
the right of the selected device should flash
GREEN when ready and flash AMBER when heat-
ing.
Once device is selected, press the set temperature
increment or decrement to set appropriate actual
temperature within selected range. See Temperature
Range Chart, page 15.
The pump will not operate until the tank is within
90% of set temperature. The tank is at temperature
when all device LEDs are flashing GREEN.
1. Press the pump on/off ON.
2. To set the pump to cycle, crawl, or run, press the
pump function toggle . For pump function
description, see Front panel display chart on page
8. The LEDs will show RED when tank is not ready
or pump control is off. The LEDs will show GREEN
when ready.
3. Adjust pump speed by pressing the pump speed
increment/decrement . The pump speed indica-
tor will illuminate showing current speed level.
If pump is in crawl setting, pump speed is not
adjustable.

Operation
309832D 17
Setting auxiliary controls
Auxiliary input selection is accomplished on per channel
basis and can only be accessed when the control is in
standby mode.
Setting standby timer
Setting the standby will turn off the tank, hose, and
applicator heat for a selected amount of time. When the
standby time is complete, the tank settings automatically
resume to previous set temperatures and heating con-
tinues.
1. Press the standby toggle .
2. Press the loop select up/down to select appro-
priate auxiliary channel .
3. To activate or deactivate selected auxiliary, press
the loop select on/off . LEDs to the left of the
selection will show GREEN if on.
4. To resume operation, press the standby
toggle .
1. Press the standby toggle.
2. Press temperature increment/decrement to
increase or decrease time. Set time will appear in
the set temperature display. You must enter a mini-
mum of five minutes for standby time.

Operation
18 309832D
Dispensing material
Adjusting timers and controllers
See Timer manual 310814 for instruction. See Air Saver
Control instructions in appropriate applicator manual.
• 310801 Manual Applicator manual
• 310803 Automatic Applicator manual
Do not operate hot melt unit until material in tank is
at set temperature. The pump will not operate until
the tank is within 90% of set temperature. The tank
is at temperature when all device LEDs are flashing
GREEN.
1. Adjust panel controls, see Adjusting panel con-
trols, page 15.
2. When device indicators are flashing green, set
pump function. See Setting pump control and
speed, page 16.
• The normal mode of pump operation is the
cycle mode.
• When setting pump speed for DC motors, set
the pump speed to the lowest necessary
speed. This will maintain operating fluid pres-
sure and reduce the potential for glue degrada-
tion due to shearing in the pump.
3. Dispense the material as instructed in appropriate
applicator manual.
4. To adjust flow of material, turn the pressure regula-
tor (Q), using a 10 mm hex wrench.
• To increase flow, turn regulator clockwise.
• To decrease flow, turn regulator counterclock-
wise.
Q
Increase flow
Decrease flow

Maintenance
309832D 19
Maintenance
Daily Maintenance
Before powering up the hot melt system perform the fol-
lowing checks.
Tank Screen Inspection
A screen 118211 is located at the bottom of the tank to
prevent contaminants from damaging the pump assem-
bly. Inspect and clean screen on a regular basis. Inspect
when tank is close to or is empty of material. See Flush-
ing, page 14.
1. Inspect the melt tank for foreign materials and/or
charring of the adhesive. Wipe off all excess adhe-
sives from all surfaces with purging compound
118090.
2. Check the hoses, applicator heads, and nozzles for
wear and ensure integrity of all electrical connec-
tions.
3. Verify the hose is being properly supported so it is
not stressed during use. The minimum bend radius
is 16 in. (40.64 cm) when hot.
4. Look for leaks under the melt unit and at all
mechanical connections.

Troubleshooting
20 309832D
Troubleshooting
Problem Cause Solution
Front panel not lit. Unit not plugged in or turned on. Plug in unit. Turn on/off switch ON.
Wire harness connections not con-
nected or need replacing. Fuse dis-
connected or needs replacing.
Check all power supply connections
to the front panel. Replace if neces-
sary, see Replacing front panel,
page 25. Check fuse with ohmmeter,
replace if necessary.
Open Sensor LED is activated and
flashes RED. Affected zone LED will
flash RED.
Sensor condition is detected in the
applicator, melt unit, and/or hose.
Check hose and applicator electrical
connections. Make sure pins are
lined up correctly and are secure.
Check tank thermistor assembly with
ohmmeter, which should read
approximately 100,000 ohms at room
temperature. Replace if necessary,
see Replacing thermistor assem-
bly, page 33.
Check hose thermistor assembly with
ohmmeter. Replace hose. See
Replacing hose, page 23.
Check applicator thermistor assem-
bly. See appropriate applicator man-
ual.
Unit circuit breaker, on/off switch is
tripped.
Operator significantly lowers tank set
temperatures after tank has reached
set temperature.
Turn the circuit breaker ON and
quickly press temperature increment
, increasing desired tank temper-
ature.
Allow tank to cool below or equal to
operator’s set temperature.