Bunn H5X User Manual

Page 1
REPLACEMENT OF ANY COMPONENT!
BEFORE REMOVAL OF ANY PANEL OR
DISCONNECT FROM POWER SOURCE
!
WARNING
H5E
H5X
WARNING
!
Very Hot Water Use With Care!
BUNN-O-MATIC CORPORATION
POST OFFICE BOX 3227
SPRINGFIELD, ILLINOIS 62708-3227
PHONE: (217) 529-6601 FAX: (217) 529-6644
10420.0000K 06/05 © 1989 BUNN-O-MATIC CORPORATION
www.bunnomatic.com
Page 2
CONTENTS
Introduction ................................................. 2
Warranty...................................................... 2
User Notices ................................................ 3
Electrical Requirements ............................... 4
Plumbing Requirements .............................. 4
Initial Set-Up................................................ 5
Draining the Dispenser ................................ 5
Cleaning....................................................... 5
Troubleshooting .......................................... 6
Service......................................................... 9
Wiring Schematics..................................... 20
INTRODUCTION
This equipment heats and dispenses water on demand for beverages and cooking purposes. It has a panel above the faucet that indicates the status of the dispenser. This equipment is for indoor use, either wall-mounted or on a sturdy counter or shelf.
BUNN-O-MATIC COMMERCIAL PRODUCT WARRANTY
Bunn-O-Matic Corp. (“BUNN”) warrants equipment manufactured by it as follows:
1) All equipment other than as specified below: 2 years parts and 1 year labor.
2) Electronic circuit and/or control boards: parts and labor for 3 years.
3) Compressors on refrigeration equipment: 5 years parts and 1 year labor.
4) Grinding burrs on coffee grinding equipment to grind coffee to meet original factory screen sieve analysis: parts and labor for 3 years or 30,000 pounds of coffee, whichever comes first.
These warranty periods run from the date of installation BUNN warrants that the equipment manufactured by it will be commercially free of defects in material and workmanship existing at the time of manufacture and appearing within the applicable warranty period. This warranty does not apply to any equipment, component or part that was not manufactured by BUNN or that, in BUNN’s judgment, has been affected by misuse, neglect, alteration, improper installation or operation, improper maintenance or repair, damage or casualty. This warranty is conditioned on the Buyer 1) giving BUNN prompt notice of any claim to be made under this warranty by telephone at (217) 529-6601 or by writing to Post Office Box 3227, Springfield, Illinois 62708-3227; 2) if requested by BUNN, shipping the defective equipment prepaid to an authorized BUNN service location; and 3) receiving prior authorization from BUNN that the defective equipment is under warranty.
THE FOREGOING WARRANTY IS EXCLUSIVE AND IS IN LIEU OF ANY OTHER WARRANTY, WRITTEN OR ORAL, EXPRESS OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, ANY IMPLIED WARRANTY OF EITHER MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. The agents, dealers or employees of BUNN are
not authorized to make modifications to this warranty or to make additional warranties that are binding on BUNN. Accordingly, statements by such individuals, whether oral or written, do not constitute warranties and should not be relied upon. If BUNN determines in its sole discretion that the equipment does not conform to the warranty, BUNN, at its exclusive option while the equipment is under warranty, shall either 1) provide at no charge replacement parts and/ or labor (during the applicable parts and labor warranty periods specified above) to repair the defective components, provided that this repair is done by a BUNN Authorized Service Representative; or 2) shall replace the equipment or refund the purchase price for the equipment.
THE BUYER’S REMEDY AGAINST BUNN FOR THE BREACH OF ANY OBLIGATION ARISING OUT OF THE SALE OF THIS EQUIPMENT, WHETHER DERIVED FROM WARRANTY OR OTHERWISE, SHALL BE LIMITED, AT BUNN’S SOLE OPTION AS SPECIFIED HEREIN, TO REPAIR, REPLACEMENT OR REFUND.
In no event shall BUNN be liable for any other damage or loss, including, but not limited to, lost profits, lost sales, loss of use of equipment, claims of Buyer’s customers, cost of capital, cost of down time, cost of substitute equipment, facilities or services, or any other special, incidental or consequential damages.
2
10420 091902
Page 3
USER NOTICES
The notices on this dispenser should be kept in good condition. Replace unreadable or damaged labels.
12593.0000
00656.0000
00831.0000
3
10044.0000
10420 072500
Page 4
ELECTRICAL REQUIREMENTS
CAUTION - The dispenser must be disconnected from the power source until specified in
Initial Set-Up.
This dispenser requires 2-wire, grounded service rated 120, 208, or 240 volts ac, 20 amp, single phase.
(Refer to the dispenser’s dataplate for exact voltage requirement.)
Electrical Hook-Up
CAUTION – Improper electrical installation will damage electronic components.
WHITE
NEUTRAL L1 BLACK
120V.A.C.
1. An electrician must provide electrical service as specified.
2. Using a voltmeter, check the voltage and color coding of each conductor at the electrical source.
L2 RED
3. Remove the upper and lower rear panels. Place the tank heater switch on the electronic control assembly in the “OFF” position.
L1 BLACK
208 or 240V.A.C.
4. Install a strain relief and the proper electrical wiring to the terminal block.
5. Connect the dispenser to the power source and verify the voltage at the termi­nal block before proceeding. Reinstall both rear panels.
6. If plumbing is to be hooked-up later be sure the dispenser is disconnected from the power source. If Plumbing has been hooked-up, the dispenser is ready for
Initial Set-Up
.
4
Page 5
INITIAL SET-UP
CAUTION - The dispenser must be disconnected from the power source throughout the initial set-up, except
when specified in the instructions.
1. Remove the upper rear panel and place the tank heater switch in the “OFF” position and replace the panel.
2. Connect the dispenser to the power source and turn-on the water supply.
3. Water will automatically flow into the tank to the proper level and shut-off. This will take approximately 10 minutes.
4. Disconnect the dispenser from the power source, remove the up­per rear panel and place the tank heater switch in the “ON” posi­tion, and replace the panel.
5. Connect the dispenser to the power source and wait approximately twenty minutes for the water in the tank to heat.
6. On models with ready indicator, the indicator will glow when the
P1771
proper water temperature for use is achieved.
NOTE - Discontinue dispensing if the indicator LED turns off. Dispense only when the indicator LED glows.
DRAINING THE DISPENSER
CAUTION - The dispenser must be disconnected from the power source throughout these steps.
1. Disconnect the dispenser from the power source.
2. Shut-off and disconnect the incoming water supply
3. Remove the 4-40 screws at the sides of the top panel.
4. Gently remove one of the grommets from the tank lid.
5. Insert a tube to the bottom of the tank and syphon ALL of the water out. Bunn-O-Matic has a syphon assem-
bly available (#12440.0000) for this purpose.
NOTE - The dispenser must be full using the INITIAL SET-UP steps before reconnecting to the power source.
CLEANING
The use of a damp cloth rinsed in any mild, non-abrasive, liquid detergent is recommended for cleaning all
surfaces on Bunn-O-Matic equipment.
WALL MOUNTED INSTALLATION
If the dispenser is wall mounted, the bottom of the dispenser should be at the same height as a counter or table top. Use B.O.M. part #12542.0000 for side mounted Wall Bracket Kit or # 13125.0001 for front mounted Wall Bracket Kit .
SUPPORT FOR LARGE RECEPTACLES
CAUTION: If the dispenser is to be used with larger receptacles such as pitchers or pots, those receptacles must
be adequately supported during dispensing of hot water to avoid spillage of very hot water. This support may be provided by a table or counter top, or use B.O.M. part #12599.0000 Shelf Kit
5
10420 072500
Page 6
TROUBLESHOOTING
A troubleshooting guide is provided to suggest probable causes and remedies for the most likely problems
encountered. If the problem remains after exhausting the troubleshooting steps, contact the Bunn-O-Matic Tech­nical Service Department.
Inspection, testing, and repair of electrical equipment should be performed only by qualified service person­nel.
All electronic components have 120 – 240 volt ac and low voltage dc potential on their terminals. Shorting of terminals or the application of external voltages may result in board failure.
Intermittent operation of electronic circuit boards is unlikely. Board failure will normally be permanent. If an intermittent condition is encountered, the cause will likely be a switch contact or a loose connection at a terminal or crimp.
Solenoid removal requires interrupting the water supply to the valve. Damage may result if solenoids are energized for more than ten minutes without a supply of water.
The use of two wrenches is recommended whenever plumbing fittings are tightened or loosened. This will help to avoid twists and kinks in the tubing.
Make certain that all plumbing connections are sealed and electrical connections tight and isolated.
This dispenser is heated at all times. Keep away from combustibles.
WARNING
Exercise extreme caution when servicing electrical equipment.
Disconnect the dispenser from the power source when servicing, except when electrical tests are speci-
fied.
Follow recommended service procedures
Replace all protective shields or safety notices
Problem
Equipment will not operate.
Probable Cause
1. No power or incorrect voltage
2. Safety overflow switch
Remedy
(A) Check the terminal block for the cor­rect voltage. It should be: a.) 100 to 120 volts ac across the black and white terminals for 100 to 120 volt models or, b.) 200 to 240 volts ac across the red and black terminals for 200 to 240 volt models. or, c.) 230 volts ac across the red and black terminals for 230 volt models.
(B) Check circuit breakers or fuses.
Refer to Service – safety overflow switch for testing procedures. See page 17.
6
10420 091902
Page 7
TROUBLESHOOTING (cont.)
Problem Probable Cause Remedy
Automatic refill will not operate after drawing hot water.
Water flows into the tank con­tinuously (Dispenser discon­nected from power source).
1. No water
2. Water strainer/flow control
3. Safety overflow switch
4. Liquid level system
5. Solenoid valve
1. Solenoid valve
Check plumbing and shut-off valves.
(A) Direction of flow arrow must be point­ing towards dispenser.
(B) Remove the strainer/flow control and check for obstructions. Clear or replace.
Refer to Service – safety overflow switch for testing procedures. See page 17.
Refer to Service – electronic controls for testing procedures. See page 10.
Refer to Service – solenoid valve for test­ing procedures. See page 18.
Refer to Service – solenoid valve for test­ing procedures. See page 18.
Water flows into the tank con­tinuously (Dispenser connected
1. Liquid level system
Refer to Service – electronic controls for testing procedures. See page 10.
to power source).
Water is cold.
1. Tank heater switch
Tank heater switch must be in the “ON” position.
2. Safety overflow switch
Refer to Service – safety overflow switch for testing procedures. See page 17.
3. Limit thermostat
Refer to Service – limit thermostat for test­ing procedures. See page 16.
CAUTION – Do not eliminate or bypass limit thermostat. Use only B.O.M. replacement part #23717.0001.
4. Tank heater
Refer to Service – tank heater for testing procedures. See page 19.
5. Temperature control
Refer to Service – electronic controls for testing procedures. See page 10.
7
10420 011599
Page 8
TROUBLESHOOTING (cont.)
Problem Probable Cause Remedy
Water boils continuously.
1. Temperature control
Refer to Service – electronic controls for testing procedures. See page 10.
2. Lime build-up
Inspect the tank assembliy for excess lime deposits. Delime as required.
CAUTION – Tanks and tank components should be delimed reglarly depending on local water conditions. Exces­sive mineral build-up on stainless steel surfaces can initiate corrosive reactions resulting in serious leaks.
Dispenser is making unusual noises.
1. Solenoid valve
2. Plumbing lines
The nut on top of the solenoid valve must be tight or it will vibrate during operation.
Plumbing lines should not be resting on the counter top.
3. Water supply
(A) The dispenser must be connected to a cold water line.
(B) Water pressure to the dispenser must not be higher than 90 psi (620 kPa). Install a regulator if necessary to lower the work­ing pressure to approximately 50 psi (345 kPa).
Ready indicator will not light. (when temperature is within 4° of its selected setting.)
1. Temperature control
2. Ready Indicator LED
Refer to Service – electronic controls for testing procedures. See page 10.
Replace the indicator LED.
8
10420 072500
Page 9
SERVICE
This section provides procedures for testing and replacing various major components used in this dis­penser should service become necessary. Refer to Troubleshooting for assistance in determining the cause of any problem.
Component Access
WARNING – Disconnect the dispenser from the power
source before the removal of any panel or the replace­ment of any component.
The limit thermostat, liquid level probe, tank heater, and temperature sensor are located at the top of the dispenser. Access is gained by removing the top lid, attached with three 4-40 slotted-head screws.
The triac assembly is located beneath the tank. Access is gained by removing four feet and the bottom panel attached with seven 8-32 slotted-head screws.
NOTE - Completely drain the tank before tipping the dispenser.
WARNING – Inspection, testing, and repair of electrical equipment should be performed only by qualified ser­vice personnel. Disconnect the dispenser from the power source when servicing, except when electrical tests are required and the test procedure specifically states to connect the dispenser to the power source.
Electronic Controls ............................................. 10
Limit Thermostat ................................................ 16
Safety Overflow Switch....................................... 17
Solenoid Valve .................................................... 18
Tank Heater ........................................................ 19
Electronic Control Assembly Troubleshooting:
Check these items first
Is circuit board popped-out of bracket?
Is circuit board wet due to misaligned overflow
tube?
Is water in overflow cup activating float switch?
Is overflow cup not making good contact with tank?
Is dispenser being operated with panels removed?
9
Page 10
SERVICE (cont.)
Electronic Controls
Location:
The electronic control assembly is located inside the rear of the dispenser. Access will also be needed to the temperature sensor, overflow tube temperature sensor, and liquid level probe located on the tank lid and to the triac assembly located beneath the tank.
General:
This system controls the liquid level and water tem­perature of the dispenser. These two functions act in­dependently of each other and should be tested sepa­rately.
Liquid Level Control Flow Charts
10
Page 11
SERVICE (cont.)
Electronic Controls (cont.)
Liquid Level Control Test Procedure
1. Disconnect the dispenser from the power source.
2. Check the voltage across terminals 3 & 4 of the electronic control assembly with a voltmeter. Con­nect the dispenser to the power source. The indi­cation must be: a.) 100 to 120 volts ac for 100 to 120 volt models or b.) 200 to 240 volts ac for 200 to 240 volt models or c.) 230 volts ac for 230 volt models.
3. Disconnect the dispenser from the power source. If voltage was present as described, proceed to #4. If voltage was not present as described, refer to the Wiring Diagrams and check the dispenser wir­ing harness.
4. Remove the pink wire from terminal 5 of the elec­tronic control assembly.
5. Check the voltage across terminals 1 & 4 of the electronic control assembly with a voltmeter. Con­nect the dispenser to the power source. The indi­cation must be: a.) 100 to 120 volts ac for 100 to 120 voltmodels or b.) 200 to 240 volts ac for 200 to 240 volt models or c.) 230 volts ac for 230 volt models after a delay of approximately 5 seconds.
6. Disconnect the dispenser from the power source.
If voltage was present as described, the liquid level control of the system is operating properly, proceed to #7. If voltage was not present as described, replace the electronic control assembly and the temperature sen­sor in the tank lid.
NOTE - Each electronic control assembly is calibrated to a temperature sensor. Both components MUST be replaced as a set.
Temperature Control Flow Charts
H5X THERMOSTAT
PROBLEM: Water Not Hot Enough
Jumper JP1
In Boil Position
?
Ye s
Red Light On
Constantly
?
Ye s
Measure Voltage
At Tank Heater
Voltage Present
?
No
Limit Thermostat OK
?
Ye s
Replace Control Assembly
Measure Voltage
At Tank Heater
Voltage Present
?
Ye s
Recheck Water Temperature
No
Reposition Jumper
No
Replace Steam Sensor
Ye s
Replace Tank Heater
No
Replace Limit Thermostat
No
Check For Split Tank Heater
Replace Triac
Reinstall Original Control Assembly
Red Light On
Replace Control Assembly
Constantly
?
No
Ye s
Recheck Water Temperature
H5E THERMOSTAT
PROBLEM: Water Not Hot Enough
Red Light On
Constantly
?
Ye s
Measure Voltage
At Tank Heater
Voltage Present
?
No
Limit Thermostat OK
?
Ye s
Replace Control Assembly
Measure Voltage
At Tank Heater
Voltage Present
?
Ye s
Recheck Water Temperature
No
Clockwise Contiuously
Ye s
Replace Tank Heater
No
Replace Limit Thermostat
No
Check For Split Tank Heater
Turn Temperature Adjustment Screw
Replace Triac
Reinstall Original Control Assembly
Red Light On
?
No
Replace Control Assembly
Ye s
Adjust For Correct
Water Temperature
11
10420 091902
Page 12
SERVICE (cont.) Electronic Controls (cont.)
7. Reconnect the pink wire to terminal 5 of the elec­tronic control assembly.
8. Loosen the compression fitting, remove the probe from the tank lid, and inspect it for mineral depos­its. Replace it if necessary. Keep the exposed ends of the probe away from any metal surface of the dispenser.
9. Check the voltage across terminals 1 & 4 of the electronic control assembly with a voltmeter. Con­nect the dispenser to the power source. The indi­cation must be: a.) 100 to 120 volts ac for 100 to 120 volt models or b.) 200 to 240 volts ac for 200 to 240 volt models or c.) 230 volts ac for 230 volt models after a delay of approximately 5 seconds.
10. Touch the screw head end of the probe to the dis­penser housing. The indication must be 0.
11. Move the probe away from the dispenser housing. The indication must again be: a.) 100 to 120 volts ac for 100 to 120 volt models or b.) 200 to 240 volts ac for 200 to 240 volt models or c.) 230 volts ac for 230 volt models after a delay of approximately 5 seconds.
12. Disconnect the dispenser from the power source.
If voltage was present as described, reinstall the probe, the sensing function of the system is operating prop­erly. If voltage was not present as described, check the pink probe wire and the green ground wire for continuity and/or replace the probe.
Temperature Control Test Procedure
1. Disconnect the dispenser from the power source.
2. Check the voltage across terminals 3 & 4 of the electronic control circuit board with a voltmeter. Connect the dispenser to the power source.The in­dication must be: a.) 100 to 120 volts ac for 100 to 120 volt models or b.) 200 to 240 volts ac for 200 to 240 volt models or c.) 230 volts ac for 230 volt models.
3. Disconnect the dispenser from the power source.
If voltage was present as described, proceed to #4. If voltage was not present as described, refer to the Wiring Diagram and check the dispenser wiring har­ness.
4. Connect the dispenser to the power source and place the tank heater switch in the “ON” position.
5. Observe the red indicator on the electronic control circuit board.
6. Disconnect the dispenser from the power source.
Temperature Control Flow Charts (cont.)
H5X THERMOSTAT
PROBLEM: Boils Excessively - Fills Cup
Drain cup
Retry
Red Light On While
Boiling
?
No
Disconnect Blue Wire From
Control Board Pin 7
Retry
Still Boiling
?
No
Replace Control Assembly
Ye s
Ye s
Replace Steam Sensor
Still Boiling
?
No
Finished
Replace Triac Assembly
Check For Split
Tank Heater
Ye s
Replace Control Assembly
12
H5E THERMOSTAT
PROBLEM: Boils
Drain cup
Retry
Red Light On While
Boiling
?
No
Disconnect Blue Wire From
Control Board Pin 7
Retry
Still Boiling
?
No
Replace Control Assembly
Ye s
Replace Control Assembly
Ye s
Replace Triac Assembly
Check For Split
Tank Heater
10420 091902
Page 13
SERVICE (cont.)
Electronic Controls (cont.)
If the indicator was on or blinking, the temperature sen­sor is operating properly, proceed to #7. If the indicator was off, check the sensor connection on the electronic control circuit board and/or replace the temperature sensor and the electronic control as­sembly.
NOTE - Each temperature sensor is calibrated to an electronic control assembly. Both components MUST be replaced as a set.
7. Check the voltage across the tank heater terminals with a voltmeter. Connect the dispenser to the power source. The indication must be: a.) 100 to 120 volts ac for 100 to 120 volt models or b.) 200 to 240 volts ac for 200 to 240 volt models or c.) 230 volts ac for 230 volt models, while the red indicator on the circuit board is on or blinking.
8. Disconnect the dispenser from the power source.
If voltage was present as described, the temperature control of the system is operating properly. If voltage was not present as described, contact Bunn­O-Matic to order an electronic control assembly, tem­perature sensor, and triac assembly for evaluation and proceed to #9.
9. Replace the electronic control assembly and tem­perature sensor.
NOTE - Each electronic control assembly is calibrated to a temperature sensor. Both components MUST be replaced as a set.
10. Check the voltage across the tank heater terminals with a voltmeter. Connect the dispenser to the power source. The indication must be: a.) 100 to 120 volts ac for 100 to 120 volt models or b.) 200 to 240 volts ac for 200 to 240 volt models or c.) 230 volts ac for 230 volt models, while the red indicator on the circuit board is on or blinking.
11. Disconnect the dispenser from the power source.
If voltage was present as described, return the new triac assembly to Bunn-O-Matic for credit. The tem­perature control of the system is operating properly. If voltage was not present as described, reinstall your existing electronic control assembly and temperature sensor, and proceed to #12.
12. Replace the triac assembly.
13. Check the voltage across the tank heater terminals with a voltmeter. Connect the dispenser to the power source. The indication must be: a.) 100 to 120 volts ac for 100 to 120 volt models or b.) 200 to 240 volts ac for 200 to 240 volt models or c.) 230 volts ac for 230 volt models, while the red indicator on the circuit board is on or blinking.
14. Disconnect the dispenser from the power source.
If voltage was present as described, the temperature control of the system is operating properly. Return the new electronic control assembly and temperature sen­sor to Bunn-O-Matic for credit.
13
10420 091902
Page 14
SERVICE (cont.)
Electronic Controls (cont.)
Electronic Controls Removal and Replacement
NOTE - Each electronic control assembly is calibrated to a temperature sensor probe. Both components MUST be replaced as a set.
1. Remove all wires from the electronic control as­sembly terminals.
2. Remove the two 8-32 screws holding the electronic control assembly to the component bracket.
3. Disconnect the temperature sensor, overflow tube temperature sensor, and indicator wires from the left side of the electronic control assembly board.
4. Remove the temperature sensor from the grom­met in the tank lid.
5. Install the new temperature sensor into the grom­met on the tank lid. Route the wires to the location of the new electronic control assembly.
6. Attach the temperature sensor, overflow tube tem­perature sensor, and indicator wires to the elec­tronic control assembly.
7. Fasten the new electronic control assembly to its bracket.
BLU to Triac Assy WHI/BRN to Tank Heater Switch
TAN to Triac Assy
PNK to Liquid Level Probe WHI or RED to Terminal Block BLK to Overflow Safety Switch GRN or GRN/YEL to Chassis Ground WHI/BLU to Solenoid
P1774
FIG. 3 WIRING CONNECTIONS
WHI & WHI to Temperature Sensor
PNK & GRY to Heater Indicator Refill Indicator Power Indicator Ready Indicator
8. Reconnect the wires.
9. Review the initial set-up procedures.
Triac Assembly Removal and Replacement
NOTE - Each triac installation requires the use of an approved silicone heat sink compound. Bunn-O-Matic recommends the use of Dow Corning 340 compound or equivalent. It can be purchased direct from Bunn-O­Matic (part # 12572.0002).
1. Place the tank heater switch on the electronic con­trol assembly in the “OFF” position.
2. Completely drain the tank.
3. Carefully set the dispenser on its face (faucet side).
4. Remove the four feet attached with four 8-32 phillips-head screws.
5. Remove the bottom panel and four feet attached with seven 8-32 slotted-head screws.
6. Remove the existing triac assembly held in place with a 10-32 hex keps nut.
7. Apply a small amount of the silicone heat sink com­pound to the copper heat sink.
8. Securely fasten the new triac assembly to the bot­tom of the tank in the same relative position as the one removed. Bunn-O-Matic recommends tighten­ing the nut to a torque setting of approximately 18 inch-pounds.
9. Route the wires up around the rear of the dispenser.
10. Reinstall the bottom panel and four feet.
11. Stand the dispenser upright.
12. Disconnect the other ends of the old triac assem­bly wires.
13. Connect the TAN and BLU wires with spade termi­nals of the new assembly to the electronic control assembly, FIG. 3.
14. Connect the BLU wire with the ring terminal to the tank heater, FIG. 13.
15. Connect the WHI/VIO wire of the new assembly to the WHI or RED terminal at the terminal block.
GRY & GRY toThermistor
FIG. 4 WIRING CONNECTIONS
P1774
14
10420 0919021510420 060305
Page 15
SERVICE (cont.)
Electronic Controls (cont.)
Adjustments
The H5X dispenser holds the water temperature at the threshhold of boiling. It is not adjustable by the user.
The H5E dispenser is factory calibrated for the tem­perature specified on the data plate. If adjustment is required, use the following procedure:
1. Fill the dispenser according to the steps in the Ini-
tial Set-up.
2. Place the tank heater switch in the “ON” position
and observe the glowing red indicator near the right
edge of the control board. The controller is apply-
ing full power to the heater when the indicator is
on all the time. The indicator will begin to flash as
the temperature nears the set point. The set tem-
perature is reached when the indicator flashes only
very briefly. The water is hotter than the set tem-
perature when the indicator remains off.
4A. TO INCREASE THE TEMPERATURE
Turn the adjustment screw in a clockwise direction with a small screwdriver. Allow the temperature to stabilize as described in step 2 and repeat step 3. Continue until the desired water temperature is achieved.
4B. TO DECREASE THE TEMPERATURE
Turn the adjustment screw in a counterclockwise direction with a small screwdriver. Draw a large quantity of water at the faucet, allow the tempera­ture to stabilize as described in step 2 and repeat step 3. Continue until the desired water tempera­ture is achieved.
NOTE - The entire adjustment span is approximately 25 complete revolutions. The potentiometer will cease to adjust when turned too far in either direction. It is not damaged, simply turn it back a few turns and try again.
3. Take the temperature of the stream of water imme-
diately below the faucet as it flows from the dis-
penser with an accurate thermometer. Do not take
the temperature of water collected in a container.
FIG. 5 TEMPERATURE ADJUSTMENT SCREW
P1774
Page 16
SERVICE (cont.)
Limit Thermostat
Location: The limit thermostat is located on the tank lid. To test the limit thermostat, access will also be needed to the terminal block located at the rear of the dispenser.
P1772
FIG. 6 LIMIT THERMOSTAT
Test Procedure:
1. Disconnect the dispenser from the power source.
2. There are two black wires on the limit thermostat terminals. One comes from the terminal block. The other goes directly to the tank heater terminal. Remove the black wire at the limit thermostat com­ing from the terminal block.
3. Check the voltage across the black wire removed from the limit thermostat and the white wire or red wire of the terminal block with a voltmeter. Con­nect the dispenser to the power source. The indi­cation must be: a.) 100 to 120 volts ac for 100 to 120 volt models or b.) 200 to 240 volts ac for 200 to 240 volt models or c.) 230 volts ac for 230 volt models.
4. Disconnect the dispenser from the power source.
If voltage was present as described, reconnect the black wire and proceed to #5. If voltage was not present as described, refer to the Wiring Diagrams and check the dispenser wiring har­ness.
5. Check for continuity across the terminals of the limit thermostat.
If continuity is not present as described, the circuit is broken. Press the reset button of the limit thermostat and recheck for continuity. If continuity is not present as described, replace the limit thermostat.
Removal and Replacement:
1. Remove both wires from the limit thermostat ter­minals.
2. Remove the two #10-32 nuts attaching the limit thermostat to the top of the tank.
3. Install the new limit thermostat and secure into place with two #10-32 nuts.
4. Refer to FIG. 7 when reconnecting the wires.
BLK to Terminal Block
BLK to Tank Heater
Reset
P1776
FIG. 7 LIMIT THERMOSTAT WIRING
16
10420 091902
Page 17
SERVICE (cont.)
Safety Overflow Switch
FIG. 8 SAFETY OVERFLOW SWITCH
Location: The safety overflow switch is located inside the rear of the dispenser inside the copper overflow cup. For testing or removal of the safety overflow switch, access may also be needed by removing the two screws attaching the electronic control assembly to its mount­ing bracket.
Test Procedure:
1. Once voltage is verified at the power source, check for continuity across the safety overflow switch red wires only until the plastic float is raised and check that continuity returns when the plastic float is again lowered.
If continuity is present as described, reconnect each of the red wires to the black wires, the safety overflow switch is operating properly. If continuity is not present as described, replace the safety overflow switch.
FIG. 9 SAFETY OVERFLOW WIRING
17
Page 18
SERVICE (cont.)
Solenoid Valve
Location: The solenoid valve is located inside the rear of the dis­penser on the right side near the bottom. To test the solenoid valve, access will also be needed to the electronic control assembly.
7. Check the solenoid valve for coil action. Connect the dispenser to the power source. Listen carefully in the vicinity of the solenoid valve for a “clicking” sound after approximately 5 seconds, as the coil magnet attracts the plunger.
8. Disconnect the dispenser from the power source.
9. Reconnect the pink wire to terminal 5 of the elec­tronic control assembly.
If the sound was heard as described and water will not pass through the solenoid valve, there may be a block­age in the water line before or after the solenoid valve or the solenoid valve may require inspection for wear and removal of waterborne particles. If the sound was not heard as described, replace the solenoid valve.
Removal and Replacement:
1. Remove all wires from the solenoid valve coil.
2. Turn-off the water supply to the dispenser.
3. Disconnect the water lines to and from the sole­noid valve.
4. Remove the two 8-32 slotted-head screws holding the solenoid valve and mounting bracket to the component bracket.
5. Lift-out the solenoid valve.
6. Remove the two 10-32 slotted-head screws hold­ing the solenoid valve to its mounting bracket.
7. Securely install the new solenoid valve to its mount­ing bracket. The direction of flow arrow must be pointing towards the tank lid.
8. Attach the solenoid valve and mounting bracket to the component bracket.
9. Securely fasten the water lines to and from the so­lenoid valve.
10. Reconnect the wires, FIG. 11.
18
Page 19
SERVICE (cont.)
Tank Heater
Location: The tank heater is located in the tank lid.
FIG. 12 TANK HEATER
Test Procedure:
1. Disconnect the dispenser from the power source.
2. Check the voltage across the terminals of the tank heater with a voltmeter. Connect the dispenser to the power source. The indication must be: a.) 100 to 120 volts ac for 100 to 120 volt models or
b.) 200 to 240 volts ac for 200 to 240 volt models or c.) 230 volts ac for 230 volt models.
3. Disconnect the dispenser from the power source.
FIG. 13 TANK HEATER WIRING
If voltage is present as described, proceed to #4. If voltage is not present as described, replace the tank heater.
4. Remove the tank heater from the tank lid and in­spect it for cracks in the sheath.
If the sheath shows no sign of damage, proceed to #5. If the sheath is damaged, replace the tank heater.
5. Check for continuity across the tank heater termi­nals.
If continuity is present as described, reinstall the tank heater. The tank heater is operating properly. If continuity is not present as described, replace the tank heater.
19
Page 20
202122
Page 21
Page 22
WIRING DIAGRAMS
L1
SCHEMATIC WIRING DIAGRAM H5XA, H5EA
RFI SUPPRESSION
CAPACITOR
GRN/YEL
N
BLK
BLK
THERMOSTAT
REFILL
PNK
PNK
LIMIT
BLK
HEATER
PNK G R Y
GRY
RED RED
GRY
PNK
GRY
READYPOWER
SAFETY
SW
THERMAL
FUSE
W H
I
H5XA Only
G R Y
BLK BLK
t°
t°
BLK
TANK HEATER
W
H
I
G R Y
EMI FILTER
GRN/YEL
TANK
HEATER
SW
ELECTRONIC
CONTROL
ASSY
THERMAL
FUSE
BLU
RED RED
TAN
7 6
5 4 3 2
1
BLU
WHI/BRN
PNK 20
(PROBE)
WHI/BLU RED
GRN/YEL
230 VOLTS A C
2 WIRE
TRIAC
WHI/VIO
RED
SOL
SINGLE PHASE
10332.0001B 09/02 © 2002 BUNN-O-MATIC CORPORATION
10420 091902
Loading...