Service - Right Side Panel Components; Compressor Relay - Bunn Ultra NX Service & Repair Manual

SERVICE - RIGHT SIDE PANEL COMPONENTS

Compressor Relay

FIG. 32 RELAY
Location:
The relay is located inside the dispenser chassis
just to the right of the condenser fan.
Right Panel Removal:
1. Loosen 2 right side panel screws on the
underside of the machine.
2. Grab and lower the right panel while pulling the
bottom outward to remove panel.
Test Procedures:
NOTE: The "Compressor Test" menu will allow the
technician to test the operation of the relay coil to
ensure power is switched across the relays
contacts and onto the compressor start up circuit.
1. Enter the software program and scroll to main
"Service Tools" menu.
2. Press the "Right Dot" switch to answer "Yes".
3. Press the "Center Dot" switch to advance onto
"Test Outputs" menu.
4. Press the "Right Dot" switch to answer "Yes".
5. Press the "Center Dot" switch to scroll through
the menus until "Compressor Test" menu is
displayed.
6. Press the "Right Dot" switch to answer "Yes" to
advance onto "Compressor" menu.
7. Press the "Left Dot" switch to answer "ON".
"Compressor" will operate.
No compressor operation, continue with testing
procedure.
8. Check relay coil for 24VDC during "Compressor"
test. See FIG. 33.
No 24VDC across relay coil terminals, replace
control board.
Yes 24VDC across relay coil terminals, continue
with testing steps.
9. Disconnect dispenser power to remove wires
from the relay normally open contact terminals.
10. Next, adjust meter to read continuity. Place
leads across relay contact/terminals. Must read
no continuity until you turn On "Compressor"
outlined in steps 1 thru 7. See. FIG 33.
11. Press the "Left Dot" switch to answer "ON".
"Compressor" relay contact terminals should
switch from an open position (no continuity) to
a closed position (continuity). Meter will sound
an audible alarm or show 0.00 on the display to
indicate continuity.
No continuity across relay contacts during test,
replace relay.
Relay Rating:
CONTACTS: SPST-NO 30A @ 400VAC
COIL: 24VDC
(OPERATE: 2.4-18VDC, 350 OHMS, 1.7W)
Part Removal and Replacement:
1. Disconnect power from machine.
2. Note the color of wire to each terminal on the
relay before disconnecting the wires from the
relay terminals.
3. Remove 2 nuts securing the relay to the
machine frame. Discard relay.
4. Install replacement relay and secure with the
2 nuts.
5. Reconnect the wires to the relay terminals.
Contact Terminals
Coil Terminals
FIG. 33 RELAY
51