Bunn CWTF-APS-MV Operating & Service Manual Download Page 15

Page 15

SERVICE (cont.)

CONTROL THERMOSTAT

Location:

 The control thermostat is located inside the trunk

on the upper left side of the component bracket.

Test Procedures:
1. Disconnect the brewer from the power source.
2. Locate the blue wire on the control thermostat.
3. With a voltmeter, check the voltage across the blue

wire on the control thermostat and the white insert
on two wire 120 volt, three wire120/208 volt or
120/240 volt terminal block. Connect the brewer to
the power source. The indication must be:
a) 120 volts ac for two wire 120 volt models.
b) 120 volts ac for three wire 120/208 volt models
or 120/240 volt models.

4. Disconnect the brewer from the power source.

If voltage is present as described, proceed to #5.
If  voltage  is  not  present  as  described,  refer  to  the
Wiring Diagrams  and check the brewer wiring har-
ness.

5. Locate the black wire on the control thermostat.
6. Gently  remove  the  capillary  bulb  and  grommet

from the tank.

7. With  a  voltmeter,  check  the  voltage  across  the

black wire of the control thermostat and the white
insert on two wire 120 volt model, three wire 120/
208 volt model or three wire 120/240 volt model
terminal  blocks  when  the  control  thermostat  is
turned fully clockwise. Connect the brewer to the
power source. The indication must be:

a) 120 volts ac for two wire 120 volt models.
b) 120 volts ac for three wire 120/208 volt models
or 120/240 volt models.

8. Disconnect the brewer from the power source.

If voltage is present as described, reinstall the capillary
tube into the tank to the line 4.5" above the bulb, the
control thermostat is operating properly.
If  voltage  is  not  present  as  described,  replace  the
thermostat.

Removal and Replacement:
1. Remove wires from control thermostat.
2. Remove the thermostat capillary bulb by firmly

pulling up on the capillary at the tank lid. This will
disengage the grommet from the tank lid.

3. Remove the one #8-32 screw securing the control

thermostat to the component bracket in the trunk.

4. Slide the grommet to the line 4.5" above the bulb

on the new capillary tube.

5. Insert the capillary bulb through the hole in the

tank lid and press the grommet firmly and evenly
so that the groove in the grommet fits into the tank
lid.

6. Carefully bend the capillary tube so that the tube

and bulb inside the tank are in the vertical position.

NOTE -

 The capillary tube must be clear of any electri-

cal termination and not kinked.

7. Using one #8-32 screw secure the control thermo-

stat to the upper left side of the component bracket
inside the trunk.

8. Refer to Fig. 3 when reconnecting the wires.
9. Adjust the control thermostat as required.

FIG. 2 CONTROL THERMOSTAT

P1415.40

28182 090100

P1382

FIG. 3 CONTROL THERMOSTAT TERMINALS

BLU to Limit Thermostat

BLK to Tank Heater
Terminal Block

Summary of Contents for CWTF-APS-MV

Page 1: ...E MANUAL BUNN O MATIC CORPORATION POST OFFICE BOX 3227 SPRINGFIELD ILLINOIS 62708 3227 PHONE 217 529 6601 FAX 217 529 6644 28182 0000C 9 00 1997 Bunn O Matic Corporation BUNN CWTF MV CWTF APS MV CWTF TS MV CWTF TSR MV ...

Page 2: ... 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 The Buyer shall give Bunn prompt notice of any claim to be made under this warranty by telephone at 217 529 6601 or by wr...

Page 3: ...Page 3 00658 0000 00656 0000 00831 0000 28181 0000 THREE WARMER BREWERS 28181 0001 ONE WARMER BREWERS 28181 0002 TWO WARMER BREWERS ALSO CWAPS CWTS CWTSR USER NOTICES CONT 02765 0000 28182 021500 ...

Page 4: ...the heater switch at the rear of the brewer in the OFF lower position 6 Remove the front panel beneath the sprayhead 7 Feed the supply leads through the rear panel of the brewer 8 Using the above diagrams connect the desired electrical service to the field wiring terminal block and remove the top cover of the brewer to verify the tank heater terminal block connections 9 The electrical service conn...

Page 5: ... The water inlet fitting is 1 4 flare NOTE Bunn O Matic recommends 1 4 copper tubing for installations of less than 25 feet and 3 8 for more than 25 feet from the 1 2 water supply line A tight coil of copper tubing in the water line will facilitate moving the brewer to clean the countertop Bunn O Matic does not recommend the use of a saddle valve to install the brewer The size and shape of the hol...

Page 6: ... stopped flowing from the funnel It should be 64 ounces 9 If not adjust the brew timer as required SeeAdjustingBrewVolumes Start and measure another brew cycle 10 Repeat step 9 until 64 oz water volume is achieved 11 The brewer is now ready for use in accordance with the coffee brewing instructions ADJUSTING BREW VOLUMES CAUTION Disconnect the power source from the brewer prior to the removal of a...

Page 7: ...l until the tank syphons down to its proper level Placing the switch in the ON upper position supplies power to enable the brew circuit on all brewers and the brew station warmer on CWTF MV Models START SWITCH Momentarily pressing and releasing the switch starts a brew cycle when the ON OFF switch is in the ON upper position NOTE The ON OFF switch must be in the ON upper position to initiate and c...

Page 8: ...ly of water Theuseoftwowrenchesisrecommendedwheneverplumbingfittingsaretightenedorloosened Thiswillhelp to avoid twists and kinks in the tubing Make certain that all plumbing connections are sealed and electrical connections tight and isolated This brewer is heated at all times Keep away from combustibles WARNING Exercise extreme caution when servicing electrical equipment Unplug the brewer when s...

Page 9: ... Refer to Service Solenoid Valve for testing procedures See page 19 A Direction of flow arrow must be pointing towards brewer B Remove the strainer flow con trol and check for obstructions Clear or replace Refer to Service Tank Heater Switchfortestingprocedures See page 23 Refer to Service Limit Thermo stat for testing procedures See page 17 Refer to Service Control Ther mostatfortestingprocedures...

Page 10: ...ding on local water condi tions Excessive mineral build up on stainless steel surfaces can initiatecorrosivereactionsresult ing in serious leaks REMEDY A Direction of flow arrow must be pointing towards the brewer B Remove the strainer flow con trol and check for obstruction Clear or replace Thebrewermustbelevelorslightly lower in front to syphon properly Inspect the tank assembly for ex cessive l...

Page 11: ...enser 2 Timer 3 Solenoid Valve REMEDY Refer to Service Control Ther mostatfortestingprocedures See page 15 Thebrewermustbelevelorslightly lower in front to syphon properly Inspect the tank assembly for ex cessive lime deposits Delime as required Remove the solenoid valve and clear any obstructions Rebuild or replace the valve if necessary See page 19 RefertoService Timerfortesting procedures See p...

Page 12: ...le shak ing Placeanemptyfunnelonanempty dispenser beneath the sprayhead Initiate a brew cycle and check the water temperature immediately below the sprayhead with a ther mometer The reading should not be less than 195 F 91 C Adjust the control thermostat to increase the water temperature Replace if necessary The BUNN paper filter must be centered in the funnel and the bed ofgroundsleveledbygentlys...

Page 13: ...king unusal noises cont Low beverage serving tempera ture CWTF Only PROBABLE CAUSE 4 Tank Heater s 1 Warmer REMEDY Remove and clean lime off the tank heater s See page 21 Refer to Service Warmer ele ment for testing procedures See page 29 28182 090100 ...

Page 14: ...t the brewer from the power source before the removal of any panel or the replace ment of any component All components are accessible by the removal of the top cover front inspection panel and warmer plate s The top cover is attached with one 4 40 screw Thefrontinspectionpanelisattachedwithfour 6 32 screws on CWTF Models six 6 32 screws on CWTF APS TS Models and eight 6 32 screws on CWTF TSR Model...

Page 15: ...be a 120 volts ac for two wire 120 volt models b 120 volts ac for three wire 120 208 volt models or 120 240 volt models 8 Disconnect the brewer from the power source Ifvoltageispresentasdescribed reinstallthecapillary tube into the tank to the line 4 5 above the bulb the control thermostat is operating properly If voltage is not present as described replace the thermostat Removal and Replacement 1...

Page 16: ...ve the cap from the fuse holder and remove the fuse 3 With an ohmmeter check for continuity through the fuse If continuity is present as described reinstall the fuse the fuse is operating properly If continuity is not present as described replace the fuse Removal and Replacement 1 Remove the cap from the holder 2 Remove fuse from the fuse holder and discard 3 Install new 20 amp fuse in the holder ...

Page 17: ...scribed the limit thermo stat is operating properly If continuity is not present as described replace the limit thermostat FIG 5 LIMIT THERMOSTAT P1415 40 SERVICE cont P1800 BLU to Control Thermostat BLK to Tank Heater Switch FIG 6 LIMIT THERMOSTAT TERMINALS Removal and Replacement 1 Remove all wires from limit thermostat terminals 2 Carefully slide the limit thermostat out from under the retainin...

Page 18: ... supply 8 Refer to Fig 8 when reconnecting the wires Location TheON OFFswitchesarelocatedonthefrontofthe hood Test Procedure 1 Disconnect the brewer from the power source 2 Viewingtheswitchfromthebackremovethewhite wire from the upper terminal and the black wire from the center terminal 3 With a voltmeter check the voltage across the white wire and the black wire Connect the brewer to the power so...

Page 19: ...itch and listen carefully in the vicinity of the solenoid valve for a clicking sound as the coil magnet attracts 7 Disconnect the brewer from the power source If the sound is heard as described and water will not pass through the solenoid valve there may be a blockage in the water line before the solenoid valve or the solenoid valve may require inspection for wear and removal of waterborne particl...

Page 20: ...ct the blue wire to the top terminal and the white red wire to thebottomterminal Theswitchisoperatingproperly If continuity is not present as described replace the switch FIG 12 START SWITCH TERMINALS P1133 28182 090100 Removal and Replacement 1 Remove the blue wire and white red wire from the start switch 2 Turn off the water supply and remove faucet 3 Remove front end cap 4 Compress the clips in...

Page 21: ...n 2 Remove the tank inlet fitting securing the fill basin to the tank lid remove fill basin splash guard and tank inlet gasket Set all parts aside for reassem bly 3 Turnoffwatersupplytothebreweranddisconnect the inlet and outlet water lines to the faucet coil assembly 4 Disconnect the black wire on the limit thermostat from the tank heater switch Disconnect the blue wire from the limit thermostat ...

Page 22: ...Page 22 SERVICE cont TANK HEATERS cont 17 Refer to Fig 14 when reconnecting the tank heater wires FIG 14 TANK HEATER TERMINALS P1420 28182 021500 ...

Page 23: ...present as described replace the tank heater switch Removal and Replacement 1 Turn off and disconnect the incoming water sup ply to the brewer 2 Gently remove the fill tube from back of fill basin 3 Remove the tank inlet fitting securing fill basin to the tank lid Remove fill basin and gasket Set all three parts aside for reassembly 4 Disconnect the water supply to coil assembly and remove the tub...

Page 24: ...n reconnecting wires 18 Reinstall the faucet tube and reconnect the water supply tube to the coil assembly 19 Secure the sprayhead tube to the hood using hex nut 20 Install sprayhead 21 Install fill basin inlet gasket and secure to tank lid with tank inlet fitting 22 Carefully install water fill tube into the back of the fill basin 23 Reconnectandturnontheincomingwatersupply 24 Refer to Fig 16 whe...

Page 25: ...bed the thermal fuse is operating properly If continuity is not present as described replace the thermal fuse FIG 18 THERMAL FUSE TERMINALS P1421 SERVICE cont Removal and Replacement 1 Disconnect the thermal fuse from the right tank heater terminal tank heater terminal block or the thermal fuse from the left tank heater terminal and the tank heater terminal block 2 Remove thermal fuse and discard ...

Page 26: ...ector from main wiring harness to the timer If voltage is present as described proceed to 8 If voltage is not present as described refer to Wiring Diagrams and check the brewer wiring harness 8 Disconnect the black and white wires to the sole noid 9 With a voltmeter check the voltage across the black and white wires when the ON OFF switch is in the ON upper position and the START switch is pressed...

Page 27: ...voltage is not as described disconnect the brewer from the power source and replace the timer 7 With a voltmeter check the voltage across termi nals TL1 and TL4 when the ON OFF switch is in the ON position Connectthebrewertothepower source and press the START switch The indica tion must be as follows a 120 volts ac for two wire 120 volt models b 120voltsacforthreewire120 208voltand120 240 volt mod...

Page 28: ... a brew volume first check that the SET LOCK switch is in the SET position on the circuit board Place the ON OFF switch in the ON position press and hold the START switch until three distinct clicks are heard and then release the switch Failure to release the switch within two seconds after the third click causes the volume set ting to be aborted and previous volume setting will remain in memory V...

Page 29: ... the two terminals on the warmer element If continuity is present as described reconnect the wires on the warmer element If continuity is not present as described replace the warmer element Removal and Replacement 1 Remove the three 4 40 screws securing the warmer assembly to the brewer 2 Lift the warmer assembly from the brewer 3 Disconnect the two wires from the warmer ele ment terminals 4 Remov...

Page 30: ...Page 30 20 AMP T1 T5 T3 T4 T2 28182 090100 ...

Page 31: ...Page 31 SCHEMATIC WIRING DIAGRAM FOR CWT APS MV CWTF APS MV CWTF TS MV CWTF TSR MV 28182 090100 ...

Reviews: