Bunn FMD-5, FMD-4 service manual Tank Heater, SERVICE cont

Models: FMD-4 FMD-5

1 45
Download 45 pages 45.11 Kb
Page 38
Image 38
TANK HEATER

SERVICE (cont.)

TANK HEATER

P2635

FIG. 35 TANK HEATER

Location:

The tank heater is located inside the tank and se- cured to the tank lid.

Test Procedure:

1.Disconnect the dispenser from the power source.

2.Check the voltage across the black and white wires 120 volt models or black and red wires for 120/208 volt models or 120/240 volt models with a voltme- ter. Connect the dispenser to the power source. The indication must be:

a)120 volts ac for two wire 120 volt models;

b)208 volts ac for three wire 120/208 volt models.

c)240 volts ac for three wire 120/240 volt models.

3.Disconnect the dispenser from the power source.

If voltage is present as described, proceed to #4.

If voltage is not present as described, refer to the dispenser wiring diagram and check the wiring har- ness.

4.Disconnect the black wire and the white or red wire from the tank heater terminals.

5.Check for continuity across the tank heater termi- nals.

If continuity is present as described, reconnect the wires, the tank heater is operating properly.

If continuity is not present as described, replace the tank heater.

NOTE - If the tank heater remains unable to heat, remove and inspect heater for cracks in the sheath.

Removal and Replacement:

1.Disconnect the dispenser from the power source.

2.Disconnect the water supply tube on the tank lid.

3.Disconnect the black wires on the limit thermstat.

4.Disconnect the black wire and the white or red wire from the tank heater terminals.

5.Disconnect the pink wire from the liquid level probe and the green wire from the tank.

6.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.

7.Remove the ten #8-32 nuts securing the tank lid to the tank.

8.Remove tank lid with limit thermostat, liquid level probe and tank heater as an assembly.

9.Remove the two hex nuts securing the tank heater to the tank lid. Remove tank heater with gaskets and discard.

10.Install new tank heater with gaskets on the tank lid and secure with two hex nuts.

11.Install tank lid with limit thermostat, liquid level probe and tank heater on the tank and secure with ten #8-32 hex nuts.

12.Connect water inlet line to the tank lid.

13.Reconnect the black wires to limit thermostat, the pink wire to the liquid level probe and the green wire to the tank. Refer to the limit thermostat and the liquid level board and probe sections in this manual when reconnecting wires.

14.Refer to Fig. 36 when reconnecting the wires to the tank heater.

WHI or RED to

BLK to Limit

Main Harness

Thermostat

 

P1218

FIG. 36 TANK HEATER TERMINALS

 

 

 

38

35135 012103

 

Page 38
Image 38
Bunn FMD-5, FMD-4 service manual Tank Heater, SERVICE cont