Grindmaster American Metal Ware P400GNB-E Guide

Grindmaster Corporation
4003 Collins Lane
Louisville, KY 40245
[phone] [phone]
[phone] (Technical Service Only)
FAX [phone]
www.grindmaster.com
1103 Form #AM-352-04
Part # A090-094
ECN # 1091
Rev. Rel.
© Grindmaster Corporation, 1998
PRINTED IN THE USA
American Metal Ware
®
Brewers
Operation and Instruction Manual
for
Model: P400GNB-E
Prior authorization must be obtained
from Grindmaster Corporation
for all warranty claims.
Model P400GNB-E
TABLE OF CONTENTS
Warning Labels........................................2
Start Up Procedures.............................3-6
Operation..............................................6-7
Adjustments..........................................7-9
Care and Cleaning............................10-12
Service..............................................12-13
Troubleshooting................................14-18
Installation Rough-In Drawings..............19
Exploded Views ................................20-25
Wiring Diagrams...............................26-27
G R I N D M A S T E R,.
CORPORATION

American Metal Ware®P400GNB-E Page 2
Warning Labels
The following warning and caution statements are contained in different sections of this manual. Please read this
manual and follow all safety precautions when operating or servicing this equipment.
CAUTION: HOT LIQUID HAZARD
WATER USED FOR BREWING COFFEE IS VERY HOT. USE CAUTION WHEN BREWING,
POURING OR TRANSPORTING COFFEE. NEVER ATTEMPT TO MOVE THE BREWER
WITHOUT FIRST DRAINING THE WATER TANK. ACCIDENTAL SPILLS MAY RESULT IN
SEVERE BURNS.
! WARNING: ELECTRIC SHOCK HAZARD
ONLY QUALIFIED SERVICE PERSONNEL SHOULD PERFORM INSTALLATION OF THIS
APPLIANCE. IMPROPER INSTALLATION COULD RESULT IN ELECTROCUTION.
CAUTION: HOT LIQUID HAZARD
COFFEE BASKET CONTAINS VERY HOT LIQUID UNTIL THE DRIP-THROUGH IS COM-
PLETED. EARLY REMOVAL OF THE BASKET COULD RESULT IN BURNS.
! WARNING: ELECTRIC SHOCK HAZARD
NEVER USE THE GROUND CONDUCTOR AS A NEUTRAL. THIS COULD CAUSE
ELECTROCUTION.
! WARNING: ELECTRIC SHOCK HAZARD
DANGEROUS ELECTRIC VOLTAGES ARE PRESENT NEAR ADJUSTABLE COMPO-
NENTS. ONLY QUALIFIED SERVICE PERSONNEL SHOULD MAKE ADJUSTMENTS.
! WARNING: ELECTRIC SHOCK HAZARD
DANGEROUS ELECTRIC VOLTAGES ARE PRESENT NEAR COMPONENTS TO BE
CLEANED AND SANITIZED. ONLY QUALIFIED SERVICE PERSONNEL SHOULD PER-
FORM THIS SERVICE. POWER TO THE UNIT MUST BE DISCONNECTED PRIOR TO
CLEANING AND SERVICING THIS UNIT.
! WARNING: BURN HAZARD
HOT LIQUIDS AND SURFACES ARE PRESENT IN THIS EQUIPMENT. TO AVOID BURNS
USE CAUTION WHEN CLEANING. RINSE POTS WITH COLD WATER BEFORE
CLEANING. USE GLOVES OR HEAVY CLOTH WHEN REMOVING HOT PARTS FROM
BREWER.

Page 3 American Metal Ware®P400GNB-E
Start Up Procedures
See rough-in drawing in this manual for dimensions and locations of electrical and water input.
Set-up / Position
1) Remove the brewer from the packing material and attach the 4” legs.
2) Position the brewer on a strong, stable table or counter top. Check the level front to back and side to side.
Adjust the legs to the correct level.
IMPORTANT: The person installing this appliance is responsible for ensuring that electric and water
connections meet the requirements of the national electric code, national plumbing code
and any local ordinances.
Water Hook-up
1) The water line may enter through hole at the rear or through the bottom of the brewer. Use the left hand open-
ing for water.
2) Use 3/8” copper or flexible water line to prevent strain. Do not use low temperature plastic tubing. The con-
nector on the fill valve is a 3/8” male flare fitting.
3) Water line pressure must be from 30 to 70 psi.
4) Hot (up to 160oF) or cold water may be used. Hot water offers faster recovery between brews.
5) Install a shut-off valve near the brewer.
6) Installing a filtering system can improve the taste of brewed coffee and extend the life of the brewer. The use
of a filter is especially important if your water has a high calcium (lime), chlorine or iron content. Contact our
Technical Service department to select the filter for your water conditions.
Electrical Hook-up
1) The electric ratings for your brewer are printed on its nameplate. The electrical rating is one of the
following:
• 120/208-240 Volt, 1 Phase, 4 supply wires (standard configuration)
• 208-240 Volt, 1 Phase, 3 supply wires (no neutral line)
• 120/208-240 Volt, 3 Phase, 5 supply wires
• 208-240 Volt, 3 Phase, 4 supply wires (no neutral line)
2) The brewer should be connected to its own circuit with a fused disconnect switch or a circuit breaker near the
brewer.
3) Attach the appropriately sized cord to the brewer with a cord grip for the 1 1/2” electric input opening. The cord
may enter through hole at the rear or through the bottom of the brewer. Use an oil resistant cord such as type
SO, SOO, SAO, STOO, SEO, SJO, SJOO, SJTO, SJTOO, SJEO, HSO, HSOO, HSJO or HSJOO.
Alternatively, flexible conduit and type THHN wires may be used. Use only copper conductors.
4) Standard configuration is 1 phase, 4 wire. Connect the three lines (L1, L2, and neutral) to the terminal block.
The neutral line must be connected to the N terminal. If your building wiring does not offer a neutral line, the
correct model must be used, see item 1. If the brewer is wired for three phase, lug L3 is provided on the termi-
nal block.
! WARNING: ELECTRIC SHOCK HAZARD!
ONLY QUALIFIED SERVICE PERSONNEL SHOULD PERFORM INSTALLATION OF THIS
APPLIANCE. IMPROPER INSTALLATION COULD RESULT IN ELECTROCUTION.

Start Up Procedures (cont.)
5) The body of the brewer must be grounded. A ground lug is provided for this purpose.
Initial Start-up
1) Turn on the water supply to the brewer. Check for leaks at the supply line to the fill valve connection.
2) Replace the front access panel.
3) Turn on the electric supply. The brewer will begin to fill. If the Water Hot light begins flashing during this initial
filling, then the water fill valve has been on for more than 5 minutes. This is an error mode, and the unit must
be reset. To reset, remove the control board access cover. Press the Select button for 10 seconds to reset the
controller and resume filling.
4) Once the brewer is full, it will take 15 - 35 minutes to heat. The Water Hot light will turn on when the water is
up to the proper brewing temperature.
5) Insert the brew baskets and place a shuttle over the warmer shelf. Brew at least 1 batch from each side.
Check the level in the container to be sure the brew volume is correct. Remember that when using coffee, the
level will be lower. Do this for both batch sizes when provided. The water must be hot to check the levels. If
adjustments are needed, see the Adjustments section of this manual.
User Control Functions
There are 2 sets of controls on the exterior of the P400GNB unit, 1 set of controls per brew station. Each set of
controls consists of a touchpad and a red Stop switch. A water faucet and a red Water Hot light are located
between the 2 sets of touchpad controls.
Touchpad Functions (Refer to Figure A): Each touchpad has 3 switch pads with symbols above each switch pad
that illuminate the selected operation.
The 1st switch (left position) is used to select the PORTION SIZE desired: 1/2 gal, 1 gal and 1 1/2 gal. Default
setting is 1 1/2 gal. Pressing the button repeatedly cycles through the 3 settings.
The 2nd switch (middle position) is used to select the operating Mode: Grind Only, Brew Only and Grind’n Brew.
Default setting is Grind’n Brew. Pressing the button repeatedly cycles through the 3 settings.
The 3rd switch (right position) is used to Start the operation. Pressing this switch starts the grinding operation, then
follows with the brewing operation. During the brewing operation, a red dot will illuminate indicating that
brewing is in progress. After the brew time is elapsed, the red dot will flash during the drip through phase of the
brewing cycle. Throughout the grinding and brewing operations, the touchpad functions are locked out from making
any changes.
NOTE: Before any operation is to be performed, the brew basket and shuttle must be in place.
Stop Switch Function: Pressing the Stop switch any time during the cycle will terminate the cycle prematurely and
reset the controller to a waiting status.
American Metal Ware®P400GNB-E Page 4
! WARNING: ELECTRIC SHOCK HAZARD
NEVER USE THE GROUND CONDUCTOR AS A NEUTRAL. THIS COULD CAUSE
ELECTROCUTION.
Figure A
PORTION
SIZE
1 1/2
MODE START
BREW
I 6
11 & O
• rn •

Page 5 American Metal Ware®P400GNB-E
Start Up Procedures (cont.)
NOTE: After stopping the cycle prematurely, there may be a period of time needed to wait for the drip
through of hot water to occur. This is a result of the brew basket collecting the hot water during a
normal brewing cycle.
Hot Water Light: This light will illuminate when the water has reached the proper brewing water temperature. The
Water Hot light is also used to display Error Codes. Go to Error Code section of the Troubleshooting Guide for
the specific details.
Hot Water Faucet: Hot water may be taken from this faucet at any time as needed.
Automatic Bypass: When brewing on the largest setting, the unit will enable the bypass valve automatically. This
is desirable to accelerate the water flow rate through the brew basket with brewing the largest volume. This allows
the correct extraction rate to be achieved for most customers.
Pre-Infusion: Pre-Infusion increases the extraction level achieved with this unit. The brewing cycle is temporarily
halted during the first portion of the cycle then resumed. This feature is standard on the unit but may be disabled if
not desired. To disable this feature, the touchpad assemblies need to be replaced. Contact our Technical Service
Department.
Low Temp No Brew: This feature prevents the operator from brewing coffee before the desired water temperature
has been reached. This feature is standard on the unit but may be disabled if not desired.
Temperature and Timing Controls (Refer to Figure B)
Temperature and the various programmable timers are set by the dial and keypad located on the control board.
This control board is located behind the lower front panel and is accessed by removing the control board access
panel.
The controller stores 12 independent timer values, 6 per brew station. Each of the 6 timers is associated with a
LED light. The top 3 LEDs control the duration of the grinding processes and are displayed in 1/10 second
increments. The bottom 3 LEDs control the duration of the brewing processes and are displayed in 1 second
increments.
Alphanumeric LEDs to indicate timer
settings and to display error codes Red LEDs to indicate which
timer is being programmed
Brewer selector switch
Water temperature adjustment knob
Figure B
TIMER NAME
SECONDS
0.5 GAL GRIND
1 GAL GRIND
1.5 GAL GRIND
0.5 GAL GRIND
1 GAL GRIND
1.5 GAL GRIND
FACTORY SETTING
LEFT RIGHT LEFT RIGHT
USER SETTING
Pushbuttons to adjust timer
values and to select timers

American Metal Ware®P400GNB-E Page 6
Start Up Procedures (cont.)
Brewer Selector Switch
The brewer selector switch is a 2 position slide switch located on the main controller. It is used to select the left or
right side timers for programming. In the left position, the left brew station is being programmed; in the right position,
the right brew station is being programmed. To switch from side to side, slide switch to the desired position.
Pushbutton Keypad
The pushbuttons serve 4 functions. These functions are to:
1) select the appropriate timer,
2) adjust the stored timing value,
3) instruct the controller to store a displayed value
4) reset the controller after an error has been registered.
The pushbutton to the right on the controller is used for 1, 3 and 4. The pushbutton to the left on the controller is
used to increase the displayed value. The middle pushbutton is used to decrease the displayed value.
To select the appropriate timer once the correct brew side has been selected, press the Select pushbutton until the
correct brew size LED is lit.
To adjust the stored timing value,press the left pushbutton to increase the displayed value or press the middle
pushbutton to decrease the displayed value.
To store a displayed value press the Select button once.
To reset the controller after an error has been registered, press the right pushbutton and hold for 10 seconds.
Temperature Adjustment Knob
Temperature adjustment is accomplished by rotating the small knob to the left of the brewer selector switch.
Clockwise rotation will increase the temperature setpoint while counter-clockwise rotation will decrease the setpoint.
Operation
1) Place an empty, warm shuttle under the sprayhead. Turn on the warmer.
2) If the shuttle is not warm, allow the warmer to heat the shuttle. A short brew of water will speed this.
A cold shuttle will significantly lower the temperature of the brewed coffee.
3) Remove the filter basket and line with a filter paper. Paper size is 13" x 5" for the BB1.5, (standard brew
basket), and 14" x 5" for the larger, BB2.0.
4) Fill the hoppers with whole coffee beans only. Your coffee supplier can help you select the right amount of
coffee and grind. Coffee brewing experts recommend 6.5 - 8 oz. of coffee per gallon of water for most applica-
tions. A full shuttle is 1.4 gal.
5) Slide the brew basket into the brewer making sure the spout lines up with the top of the shuttle or airpot.
6) Select the batch size through the touchpads. Check the Water Hot light. If it is lit, press the Start switch on the
touchpad. If the Water Hot light is not lit, wait and press Start when it illuminates.
7) Brew time is about 4 minutes for a full shuttle, less for smaller batches. After the brew, allow the coffee to drip
for 1 - 2 minutes.
CAUTION: HOT LIQUID HAZARD
WATER USED FOR BREWING COFFEE IS VERY HOT. USE CAUTION WHEN BREWING,
POURING OR TRANSPORTING COFFEE. NEVER ATTEMPT TO MOVE THE BREWER
WITHOUT FIRST DRAINING THE WATER TANK. ACCIDENTAL SPILLS MAY RESULT IN
SEVERE BURNS.

Page 7 American Metal Ware®P400GNB-E
Operation (cont.)
8) Dump the grounds from the basket and rinse for the next brew. Coffee is ready to serve.
9) The shuttle may be placed on remote warming stations. Use caution when moving a full shuttle.
Adjustments
Components for adjustment of grinding and brewing timing and of temperature are accessible behind the access
panel located on the lower front panel. The grinder adjustments are located behind the upper front cover.
Setting the Grind Profile
1) Turn off electric power to the unit at the main breaker assigned to the unit.
2) Remove the upper front panel and shield by removing the screws on the sides of the panel.
3) Loosen the adjusting screw lock nut by turning it counter-clockwise.
4) Turn the slotted adjusting screw clockwise to make the grind coarser or counter-clockwise to make the grinds
finer.
5) After adjustment has been made, re-tighten the adjusting screw lock nut.
6) Visually inspect the grind profile with a small portion of coffee and readjust if necessary.
7) Reinstall the upper front panel and shield as it was removed.
Setting the Grinder Throw Weights
The throw weight is adjusted by setting the timer values of the controller after the desired grind profile is achieved.
Refer to Temperature and Timing Controls section for more information on controls.
Before adjusting throw weight, grind a batch of coffee and measure the coffee weight. Record this value.
To adjust throw weight:
1) Remove the controller access panel.
2) Slide the brewer selector switch to the appropriate position.
3) Press the Select button momentarily; a LED will light up to indicate which timing selection is being displayed on
the alphanumeric display. Scroll down the selection list to the grinder timer to be adjusted.
4) After selecting the appropriate side and portion timer, adjust the timer value to the desired value by pressing
the Up or Down buttons on the controller. Increasing the timer value increases the coffee throw, decreasing the
number decreases the throw. Hold down the Up or Down button to scroll quickly to the desired value. Once
the desired value is displayed, press the Select button on the controller to save this new value. Grind a batch
of coffee and measure weight dispensed. Repeat this procedure as necessary until desired throw weight is
dispensed.
5) Replace the access panel.
CAUTION: HOT LIQUID HAZARD
COFFEE BASKET CONTAINS VERY HOT LIQUID UNTIL THE DRIP-THROUGH
IS COMPLETED. EARLY REMOVAL OF THE BASKET COULD RESULT IN BURNS.
! WARNING: ELECTRIC SHOCK HAZARD
DANGEROUS ELECTRIC VOLTAGES ARE PRESENT NEAR ADJUSTABLE COMPO-
NENTS. ONLY QUALIFIED SERVICE PERSONNEL SHOULD MAKE ADJUSTMENTS.
I L

American Metal Ware®P400GNB-E Page 8
Adjustments (cont.)
Water Temperature Adjustment
Brew water temperature can be adjusted by turning the knob on the main controller located behind the controller
access panel. Temperature adjustment range is 175oF - 202oF. Adjustment for temperature should be made after
measuring the temperature of the water dispensed from the sprayhead by the following procedure:
1) Remove the sprayhead from the brewer and set aside.
2) Place a shuttle without the lid under the outlet.
3) Press Start and, using a thermometer, measure the temperature of the water being dispensed.
4) If a higher temperature is desired, rotate the Temperature Adjustment knob clockwise. If a lower temperature is
desired, rotate the Temperature Adjustment knob counter-clockwise.
5) If water temperature setting has been increased, wait until heater has cycled and then follow steps 3 and 4
again. If water temperature setting has been decreased, brew a large portion of water and repeat steps 3 and 4.
6) Continue this procedure until desired brew temperature is achieved.
7) Replace sprayhead.
Brew Timing/Brew Volume Adjustment
Brew volume is adjusted by adjusting the timer values of the controller (refer to Temperature and Timing Controls
section).
Before adjusting brew timing, brew a batch of water and measure the brew volume. Record this value.
To adjust brew timing:
1) Remove the controller access panel.
2) Slide the brewer selector switch to the appropriate position.
3) Press the Select button momentarily; a LED will light up to indicate which timing selection is being displayed on
the alphanumeric display. Scroll down the selection list to the timer to be adjusted. Note the timer value displayed.
The new timing should be calculated by the following:
Desired brew volume
Desired brew time = —————————— X Current brew time
Current brew volume
4) After selecting the appropriate side and portion timer, adjust the timer value to the desired value by pressing the
Up or Down buttons on the controller. Increasing the timer value increases the brew dispensing time; decreas-
ing the number decreases the time. Hold down the Up or Down button to scroll quickly to the desired value.
Once the desired value is displayed, then press the Select button on the controller to save this new value.
5) Brew a batch of water and measure volume dispensed. Repeat procedure as necessary until desired volume is
dispensed.
6) Replace the access panel.

Page 9 American Metal Ware®P400GNB-E
Adjustments (cont.)
Bypass Adjustment (Refer to Figure C)
The bypass valve adjusts the amount of water that bypasses coffee grounds and dilutes the final brew. The
factory setting is no bypass. Bitter coffee is brewed when the amount of ground coffee is too small. Therefore, if
your coffee is brewing too strong, it is better to adjust the bypass valve instead of reducing the amount of coffee.
NOTE: Always adjust bypass before adjusting brew timing because bypass affects brew rate.
To Adjust the Bypass:
1) Turn off electrical power to the brewer and remove the upper front panel and shield.
2) Locate the bypass valve to be adjusted. The bypass valve is located to the right and in front of the brew tee.
3) Open the valve by turning the valve handle counter-clockwise to the desired setting. (Refer to the information
below.)
Bypass Setting Bypass: % Of Total Brew
Closed 0
1 revolution 8
2 revolutions 12
3 revolutions 22
4 revolutions 33
4) Measure the bypass setting:
a) Remove the brew basket.
b) Place an empty shuttle (with lid removed) under the sprayhead.
c) Place a measuring cup under the bypass outlet.
d) Press Start and brew water for about 30 seconds or until the measuring cup is almost full.
e) Record the amount of water in the bypass measuring cup.
f) Add the water from the measuring cup to the shuttle; measure the total volume and record.
Bypass % is calculated as:
Bypass % = (Bypass volume from measuring cup/total volume in shuttle) X 100
5) Adjust the bypass valve setting and repeat the measuring process until the valve is set as desired.
Figure C
AUTO BYPASS VALVE
BREW VALVE

American Metal Ware®P400GNB-E Page 10
Care and Cleaning
Cleaning After Each Brew
Dispose of grounds and rinse brew baskets. Rinse shuttles before using them again.
Daily Cleaning
The following cleaning procedure should be done on a daily basis.
1) Turn both warmer switches off. Remove the shuttle, and drain any remaining coffee from it. Thoroughly clean
the shuttle and the sight glass. Rinse and let air dry. Do not place the shuttle back on the warmer.
2) Remove the brew baskets from each side. Discard any contents in brew baskets. Clean and rinse the brew
baskets. Do not place them back on the unit.
3) Remove the spray head assembly from the spray tee assembly
(refer to Figure D). Pull the tab located at the front of the spray
head until it hits the forward stop. The sprayhead will drop
straight down and away from the spray tee nut. Clean and rinse
the spray head assembly and let air dry.
4) Clean the inside of the spray dome around the grinder outlet
chute. Use the brush provided to clean the grinder outlet chute
(refer to Figure E). Move the finger tab on the shutter door
toward the rear. Use the brush to clean up inside the grinder out-
let chute above the shutter door.
IMPORTANT: Do not insert the brush into the chute past
the stops on the brush.
Be sure to remove all the residue from the grinder outlet chute
both above and below the shutter door. Remove the brush and
release the finger tab on the shutter door.
5) Once the spray dome and grinder outlet chute are clean, the spray head assembly may be reinstalled onto the
spray tee outlet nut. Hold the tab forward on the spray head until it hits the stop. Place the spray head up
inside the spray dome. Release the hold down tab. Be sure it seats above the nut, then lock the spray head in
place inside the spray dome.
6) Do not replace the basket and shuttle on the unit. This allows the shutter mechanism to cycle and remove any
remaining residues overnight.
7) The following day, clean any coffee that may have fallen from the warmer area.
8) Place filters into the brew baskets, and install the baskets onto the unit. Place a clean shuttle onto each
warmer. Select the brew size and start the unit. Once the brew cycle has started, turn the warmer switches on.
NOTE: Cleaning brush part number is A551-079.
Cleaning During Regularly Scheduled Maintenance
To be done by a service technician during regular scheduled maintenance (not to exceed 6-month intervals)
! WARNING: BURN HAZARD
HOT LIQUIDS AND SURFACES ARE PRESENT IN THIS EQUIPMENT. TO AVOID BURNS
USE CAUTION WHEN CLEANING. RINSE HOT PARTS WITH COLD WATER BEFORE
CLEANING. USE GLOVES OR HEAVY CLOTH WHEN REMOVING HOT PARTS FROM
BREWER.
Figure D
Figure E

Page 11 American Metal Ware®P400GNB-E
Care and Cleaning (cont.)
The service technician must perform the following:
- Clean and sanitize the hopper cradle assembly
- Clean and sanitize the grinder mechanism (both stations)
- De-liming the water tank
- General cleaning and sanitizing of interior of cabinetry
Removal of Hopper Cradle Assembly
1) Remove the 4 screws that attach the upper front panel to the unit. Then remove the upper front panel.
Remove the shield by removing the 3 screws.
2) Pull the bean shut off valve forward to block the flow of coffee beans to the grind chamber. This should be
done for both hoppers.
3) Remove the 2 screws that attach the hopper cradle assembly to the front unit.
4) Lift the front edge of the hopper cradle assembly; push back a few inches to release the hopper cradle assembly
from the rear locating pins. Lift and remove the assembly from the unit.
5) Re-assembly is performed in the reverse order of disassembly.
Cleaning and Sanitizing the Hopper Cradle Assembly
1) Remove the hopper cradle assembly as described above.
2) Empty the hoppers of coffee beans.
3) Remove the bean shut-off valves from the hopper necks.
4) Remove the hoppers from the cradle assembly by removing the wing nuts and bolts.
5) All parts that are in contact with food must be washed with warm soapy water, rinsed, sanitized and air-dried.
NOTE: The person cleaning the parts should do so with clean hands.
6) Reassemble hopper cradle assembly in reverse order of disassembly.
Removal of Grinder Assembly (Both Stations)
1) Remove the hopper cradle assembly as described above.
2) Remove motor base mounting bolt from unit (one per motor assembly).
3) Disconnect electrical connection to motor at harness connector.
4) Slide motor assembly toward center of unit and lift it out of the cabinet.
5) Reinstallation is performed in the reverse order of removal.
NOTE: The grinder assembly may be installed in either left or right brew station.
Cleaning and Sanitizing the Grinder Mechanism (Both Stations)
1) Loosen the 2 slotted screws that hold the grind cap onto the grind head. Rotate the grind cap counter-clock-
wise and pull the cap forward to remove it from the assembly.
2) Rotate the feedworm assembly so the sweeps line up with the notches in the grind head. Pull the feedworm
assembly forward and off of the motor shaft.
3) All parts that are in contact with food must be washed with warm soapy water, rinsed, sanitized and air-dried.
! WARNING: ELECTRIC SHOCK HAZARD
DANGEROUS ELECTRIC VOLTAGES ARE PRESENT NEAR COMPONENTS TO BE
CLEANED AND SANITIZED. ONLY QUALIFIED SERVICE PERSONNEL SHOULD PER-
FORM THIS SERVICE. POWER TO THE UNIT MUST BE DISCONNECTED PRIOR TO
CLEANING AND SERVICING THIS UNIT.

American Metal Ware®P400GNB-E Page 12
Care and Cleaning (cont.)
NOTE: Care should be taken not getting the grinder motor wet. Also, the person cleaning the parts
should do so with clean hands.
4) To reinstall the feedworm assembly, slide the feedworm onto the motor shaft. Rotate the feedworm so the
sweeps line up with the notches in the grind head. Slide the feedworm into the grind head. While pushing
inwards, rotate the feedworm so the sweeps hold the feedworm in place.
5) Insert the shear drive into the feedworm. Using a screwdriver, rotate the shear drive so the slots line up.
6) Reassemble the remaining components in the reverse order of disassembly.
Cleaning and Sanitizing the Spout Assembly (Both Stations)
1) Remove the grinder assembly as described above.
2) Remove the 2 screws that hold the spout assembly to the sheet metal body and remove the spout assembly.
3) Remove the 4 screws that hold the upper & lower spout housings together.
4) All parts that are in contact with food must be washed with warm soapy water, rinsed, sanitized and air-dried.
NOTE: The person cleaning the parts should do so with clean hands.
5) Reassemble the components in reverse order of assembly.
De-liming the Water Tank
1) Disconnect power and remove the hopper cradle assembly as described above.
2) Disconnect the wire leads to the water heating elements, thermistor, thermodisc and water probe. Note the
positions of each wire going to the heaters and the other components.
3) Remove the tank cover by removing the 3 retaining wing nuts and lifting the cover.
4) De-lime the water tank using a commercial grade urn cleaner. Follow the recommendations from the manufac-
turer of the urn cleaner. Excessive amounts of cleaner will attack the stainless steel; therefore, caution should
be used.
5) Scrub the liner interior with a plastic bristle brush.
6) After de-liming tank, remove the brew valves and bypass valves so they can be serviced.
7) After de-liming the tank and associated components, all parts must be washed with warm soapy water, rinsed,
sanitized and air-dried.
NOTE: The person cleaning the parts should do so with clean hands.
8) Reassemble the components in reverse order of disassembly.
NOTE: When reinstalling the heater wires, be sure to return the wires to their original connection point.
Miswired heaters can cause unbalanced electrical loads and damage the unit.
Service
Service Procedures for Other Components Not Discussed in Cleaning Procedures
! WARNING: ELECTRIC SHOCK HAZARD
DANGEROUS ELECTRIC VOLTAGES ARE PRESENT NEAR ADJUSTABLE COMPONENTS.
ONLY QUALIFIED SERVICE PERSONNEL SHOULD MAKE ADJUSTMENTS.
I L

Page 13 American Metal Ware®P400GNB-E
Service (cont.)
The remainder of this manual contains information to aid the service person making repairs to this equipment. This
page has information on performing common service tasks. A Troubleshooting section follows and can be used
to help determine the cause of problems with the equipment.
An illustrated parts breakdown follows and will help correctly identify replacement parts. For factory assistance, call
1-800-568-5715 between 8:00 a.m. and 6:00 p.m. Eastern time.
Finally, wiring diagrams are provided for the various models covered by this manual.
To Drain the Water Tank
1) Turn off power to the brewer and allow the brewer to cool before draining.
2) Remove the lower front panel.
3) Pinch or clamp the tube from the fill valve to the tank and disconnect the tube from the fill valve. Place tube
over a drain, release the clamp, and allow the tank to drain.
To Remove the Brew Valve
1) Turn off power to the brewer.
2) Remove the hopper cradle assembly as described in the Removal of Hopper Cradle Assembly procedures
within the Care and Cleaning section of this manual.
3) Disconnect the wires attached to the valve.
4) Follow the To Drain Water Tank procedure on page 12 to drain the water tank below the brew valve’s water
level.
5) Tilt the inlet of the valve downward and pull sideways to disconnect the valve from the spray tee. Disconnect
the tubing from the valve.
To Remove and Replace the Heaters
1) Turn off power to the brewer.
2) Remove the hopper cradle assembly as described in the Removal of Hopper Cradle Assembly procedures
within the Care and Cleaning section of this manual.
3) Disconnect the wire leads to the heating elements, thermistor, thermodisc and water probe. Note the positions
of each wire going to the heating element and the other components.
4) Remove the tank cover after removing the 3 wing nuts securing the cover to the tank. Lift the tank cover with
the heating element attached.
5) Remove the heating element from the tank cover.
6) Replace heater with sealing washers in the same configuration; hold the element so that it does not twist when
tightening nuts.
NOTE: Make sure the thermodisc and bracket are returned to their original positions secured by the
heating element.
7) Replace the tank cover ensuring that the lid seal is positioned correctly.
8) Replace the heater wires; ensure that all electrical connections are secure. Replace the covers to the unit and
reconnect power.

American Metal Ware®P400GNB-E Page 14
Problem
Weak coffee
Strong coffee
Bitter coffee
Grounds in coffee
Brew basket
overflowed
Unpleasant taste
Brew volume too
large or too small
Possible Causes
• Not enough coffee used.
• Grind is too coarse.
• Water not hot enough.
• Too much water used.
• Coffee bed has dry areas.
• Too much coffee used.
• Grind is too fine.
• Paper filter collapsed during brewing.
• Too much coffee.
• Coffee ground too fine.
• Double batching.
• Water tank or brew basket needs
cleaning.
• Taste is coming from water supply.
• Portion selected on touchpad not
correct.
• Timer not set properly.
• Water service not supplying adequate
water pressure or flow rate.
• Sprayhead clogged.
• Brew valves clogged with lime
deposits.
Solutions
• Readjust coffee portion.
• Readjust grind to a finer grind.
• Check sprayhead temperature, should be
greater than 185oF.
• Adjust brew time at the controller.
• Spray deflector broken or missing.
• Readjust coffee portion.
• Coarsen grind setting.
• Use proper filter.
• Use no more than 9 oz. of coffee.
• Coarsen grind.
• You must dump old coffee and use fresh
new filter for each brew.
• Clean, sanitize (de-lime).
• Install a water filtration system.
• Adjust timer to desired value or select
different portion size.
• Adjust timer to desired value. Compare
timer setting to either factory setting or
initial user setting to determine if it has
been changed.
• Water pressure measured at the unit’s
water inlet valve should be between 30
psi to 70psi delivering a minimum of 1 1/2
gallons per minute.
• Remove sprayhead for cleaning. Follow
cleaning procedures for sanitizing.
• Clean lime from valve. Seat, cup or
entire valve may need replacement.
BREWING PROBLEMS
Troubleshooting
The following procedures must be performed by a qualified service technician.

Page 15 American Metal Ware®P400GNB-E
Problem
Brew volume
erratic
(NOTE: Small
variations from
batch to batch
are normal.)
Brew Only or
Grind’n Brew cycle
will not start
During Brew Only
or Grind’n Brew,
the brewing cycle
does not brew
Sprayhead will not
stop dripping water
Water boiling in
water tank
Possible Causes
• Water supply pressure fluctuates.
• Fill valve faulty or clogged.
• Water not up to proper brewing
temperature.
• Touchpad defective.
• Brew valve faulty.
• Blown fuse on control board.
• Brew valve does not close completely.
• Temperature in water tank too hot.
Solutions
• Plumb water supply so that water pres-
sure is not significantly affected by other
appliances.
• Check for power at fill valve when unit is
calling for water. If water flow is slow or
valve not operating, repair valve. In
normal operation, the fill valve should
cycle several times throughout the
brewing cycle.
• Wait for water to reach proper brewing
temperature.
• Exchange touchpad with another unit. If
problem is corrected, original unit faulty.
• Check if brew valve is energized with
120 Vac. If valve is energized and not
opened, replace part.
• Check and replace fuse if blown.
• Visually inspect valve. Clean lime from
valve. Seat, cup or entire valve may
need replacement.
• Reduce the water tank temperature.
Adjustment knob is located on the control
board face.
BREWING PROBLEMS
Problem
Hot light flashing
@ slow rate and
ER1 code dis-
played on control
board
(Also unit will not heat
water, perform any
brewing function nor
autofill)
Hot light flashing
@ fast rate and
ER2 code dis-
played on control
board
(Also unit will not heat
water or perform any
brewing function)
Possible Causes
• Fill valve opened for over 5 minutes
(this may occur on initial fill - see
Initial Start-up section).
• Water service not on.
• Water service not supplying enough
water flow.
• Loose connections in the thermistor
circuit.
• Thermistor failure.
Solutions
• Refer to Initial Start-up section to reset
the control board.
• Ensure that water supply is on.
• Water pressure measured at the unit’s
water inlet valve should be between 30
psi to 70 psi delivering a minimum of
1 1/2 gallons per minute.
• Ensure that connector CN7 is securely
attached to controller and that thermistor
is securely connected at disconnect.
• Defective thermistor, replace.
ERROR CODES
Troubleshooting (cont.)

American Metal Ware®P400GNB-E Page 16
Problem
Overfilling of water
tank when power is
off
Overfilling of water
tank when power is
on
Possible Causes
• Fill valve installed backwards.
• Fill valve not sealing properly.
• Water probe faulty or coated with lime.
• Connection from control board to tank
body or water probe faulty.
• Faulty control board.
Solutions
• Check direction of flow printed on valve.
Water flows from the water supply to the
water tank bottom.
• Disassemble, clean and reassemble
valve. If needed service kits are
available.
• Remove water probe assembly and
clean.
• Secure connection of yellow wire to tank
body and red wire to water probe
assembly. Check control board
connectors CN1 and CN7.
• Short red wire to tank body (at yellow
wire); if fill valve does not stop after 5
seconds then control board defective,
replace.
FILLING PROBLEMS
Problem
No light
illuminated on unit
No light
illuminated on
either
touchpad
No light
illuminated on one
touchpad
Water is hot but
Water Hot light not
illuminated
Possible Causes
• No power to the unit.
• No power to the unit.
• Touchpads not connected to control
board.
• Bad low voltage transformer.
• Bad control board.
• Touchpad not connected to control
board.
• Polarity of light connected reversed.
• Part defective.
Solutions
• Check if warmer lights / warmer element
operate. If not, restore power to unit.
• Check connections at terminal block.
•Connect touchpads to control board.
Assure that the left touchpad is connected
to the CN5 & right to CN6.
• Check resistance across primary termi-
nals and secondary terminals. If open
circuit, replace part.
• Check for 12 and 24 volts at control
board connector CN1 pins 2, 3 & 4. If
both
voltages present, board defective.
Replace.
• Connect touchpad to control board.
• Red wire is connected to “+” terminal of
LED light.
• If polarity correct, defective part. Replace.
PROBLEMS DISPLAYED BY INDICATOR LIGHTS
Troubleshooting (cont.)

Page 17 American Metal Ware®P400GNB-E
Solutions
• Pull bean shut-off valves forward to open
passageway.
• White and blue wires go to the left grinder
assembly. Yellow and white wires go to
the right motor assembly.
• If tripped, then reset by removing chrome
hole plugs on lower front panel. Use
pencil or other non-metallic object to
depress tripped circuit. Replace chrome
hole plugs.
• Follow shear plate replacement.
• Fuse protects all relays on control board.
If blown, replace.
• Unit will not operate until set temperature
is reached. Wait for water to reach prop-
er brewing temperature.
• Exchange touchpad with another unit. If
problem is corrected, original touchpad
unit faulty.
GRINDING PROBLEMS
Problem
No Hot Water,
Contactor does not
pull in contacts
Possible Causes
• Water is not at the water probe and
error code ER1 is displayed on control
board.
• Thermodisc tripped due to overheating.
• Thermodisc tripped due to nuisance.
• Faulty connection in the heater
circuitry from the control board through
the heater relay, thermodisc and
contactor.
• Contactor coil faulty.
• Heater relay faulty.
• Fuse blown on control board.
Solutions
• Water fill valve has been open for more
than 5 minutes. This causes error code
ER1 to occur and shut down the tank
heaters. Restore water to the unit and
reset unit.
• Reset thermodisc. Review unit to confirm
no damage occurred due to overheating
of water tank.
• Reset thermodisc. If thermodisc does not
reset or trips again, replace part.
• Secure all wire connections of the heater
circuit. Heater relay uses a 12 VDC coil;
thermodisc and contactor use 120 VAC
coil.
• Check resistance of contactor coil. If
open circuit, replace part.
• Check resistance of contactor coil. If
open circuit, replace part.
• Check fuse on control board. If blown,
replace.
HEATING PROBLEMS
Troubleshooting (cont.)
Possible Causes
• Bean shut-off valve pushed closed.
• Motor disconnect not wired or crossed
with opposite motor.
• Motor circuit breaker tripped.
• Shear plate broken.
• Blown fuse on control board.
• Water temperature not up to proper
brewing temperature (if Low Temp No
Brew is an option on unit).
• Touchpad defective.
Problem
No coffee being
discharged into
brew basket
Grind only or
Grind’n Brew cycle
does not start

American Metal Ware®P400GNB-E Page 18
Problem
No hot water,
contactor with
contacts closed
Recovery time is
very long
Possible Causes
•Line voltage connections at terminal
block, contactor or heater terminals
faulty.
• Heating element faulty.
• Contactor contacts faulty.
• Faulty heating element.
• Low temp no brew function not
allowing user to brew cold pot.
Solutions
• Secure all wire connections of the heater
circuit. Confirm that supply voltage is
present at the terminal block
and is active.
• Measure resistance of heating elements.
If open circuit between terminals and / or
tank body, replace parts.
• Check contacts of contactor. If corroded
or faulty, replace part.
• Check resistance across element with
power conductors disconnected. If resis-
tance is much less than 8 Ohms or much
more than 15 Ohms, replace part.
• Replace touchpad assemblies with
assemblies without that option if desired.
HEATING PROBLEMS
If you still need help, call our Service Department at [phone] (Monday thru Friday 8:00 a.m. - 6:00 p.m.
Eastern time) or an authorized service center in your area. Please have the model and serial number ready so that
accurate information can be given.
Prior authorization must be obtained from Grindmaster Corporation’s Technical Services Department for all warranty
claims.
Troubleshooting (cont.)

Page 19 American Metal Ware®P400GNB-E
Installation Rough-In Drawings P400GNB-E
PLAN VIEW
37"
21 5/8"
6 7/8" 4"
(2) 1 1 /4" DIA. HOLES
F-OR OPTIONAL REAR
ACCESS FOR UTILITY
CONNECTIONS. 4 1/2
11
--18"--.
11 4 1/4"
1 1/ 4" DIA. ACCESS HOLE FOR
t=:o::==="""'==-t="""'~---r-, WATER CONNECTION.
0 0
9"
19 1/8"
FRONT VIEW
CONNECTION MADE TO 3/8'" MALE FLARE.
1 1/4" D~ ~c~s HO~ rnR
ELECTRICAL CONNECTION.
22"
6 3/8
11
~
§
c::,·
23"
SIPE VIEW
STD. UTILITY
ACCESS LOCATION
49 3/4"
. ALTERNATE
UTILITY ACCESS
LOCATION

American Metal Ware®P400GNB-E Page 20
Exploded View P400GNB-E
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