Bunn U3 Manuales De Servicio

Page 4

SET

     L

OC

K

LO

CK

SE

T

FIG.18 RELAY

P1731.55

Location:
 

The relay is located on the front part of the com-

ponent  bracket,  mounted  on  the  top  of  the  timer 

bracket.

Test Procedures:

All Models Except 30V - CE Models

1.  Disconnect the brewer from the power source.

.  Disconnect the wires from relay terminals "A" & 

"B". Check for continuity between terminals "A" & 

"B".

If continuity is present as described, reconnect the 

wires to terminals "A" & "B" and proceed to #3.

If continuity is not present as described replace the 

relay.

3.   Disconnect the wires from relay terminals  & 7.

4.  Check for continuity across terminals  & 7.

If continuity is present as described, reconnect the 

wires to terminals  & 7 and proceed to # 5.

If continuity is not present as described, replace the 

relay.

5.  Disconnect the wires from relay terminals 5 & 7.

6.  Check for continuity across terminals 5 & 7 by 

manually closing relay contact. Continuity must 

not be present when contact is released.

If continuity is present as described, reconnect the 

wires, the relay is operating properly.

If continuity is not present as described, replace the 

relay.

30V - CE Models

1.  Disconnect the brewer from the power source.

.  Disconnect the black wire from relay terminal "A" 

and the red wire from relay terminal "B". Check 

the voltage across the black and red wire with a 

voltmeter. Connect the brewer to the power source. 

The indication must be 30 volts ac.

If voltage is present as described, proceed to #3.

If voltage is not present as described,  refer to the Wir-

ing Diagrams and check the brewer wiring harness.

3.  Disconnect the brewer from the power source.

4.  Check for continuity across relay terminals "A" & 

"B"

If continuity is present as described, reconnect the 

wires to terminals "A" & "B" and proceed to #5.

If continuity is not present as described, replace the 

relay.

5.  With the thermostat in the "ON" position and the 

relay  engaged  disconnect  the  brewer  from  the 

power source.

6.  Disconnect the blue wires from relay terminals 1 

and 7. Check for continuity across terminals 1 and 

7.

If continuity is present as described, proceed to #7

If continuity is not present as described, replace the 

relay.

 

7.  Turn  the  thermostat  to  the  "OFF"  position,  con-

nect the brewer to the power source and turn the 

thermostat back to the "ON" position. Continuity 

should not be present across terminals 1 & 7.

If continuity is not present as described, the relay is 

operating properly.

If  continuity  is  present  as  described,  replace  the 

relay.

10060  080900