Cornelius Quest NT 4000, Service Manual

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Quest Service Manual
Publication Number: 720901117SER - 14 - © 2004-2014, Cornelius Inc.
• Excessive demand on dispenser • Add water pre-cooler or second
dispenser
• Dirty condenser coil • Clean condenser coil
• Inoperative condenser fan • Replace condenser fan motor
• Defective Ice Bank Control • Test and replace if necessary
• Loss of refrigerant charge due to
leak in system • Repair leak and recharge system
Water continuously
drips from nozzle
when in OFF mode
• Main water solenoid at base of
unit or water solenoid on pump
platform not shutting off tightly • Clean solenoid(s), replace parts
as necessary (refer to the
Planned Maintenance Section)
Concentrate warm,
water cold
• Cabinet fan inoperable • Check/replace fan
• Agitator motor/pump inoperable
or restricted • Check/replace agitator motor
• Loss of refrigerant charge due to
leak in system • Repair leak and recharge system
Brix Problem
• Water supply pressure too low,
less than 20 psi (1.4 bar) flowing
water pressure fluctuates sharply • Correct water supply problem to
ensure a constant 50 psi (3.5 bar)
flowing to the dispenser
• Water flow control binding or
spring is defective • Clean and/or replace parts as
necessary
• Improperly thawed concentrate.
Brix changes as the concentrate
temperature changes (concen-
trate becomes thinner as temper-
ature rises) • Concentrate should be 35-40°F
(1.7-4.5°C) prior to loading
Pump Inoperative
• Pump motor defective • 28VDC should be present at
pump motor during dispense. If
voltage is present and motor does
not start, replace pump motor
• No power to transformer or no
28VAC output from transformer • Confirm transformer has line volt-
age present on primary side. If no
28VAC output from the secondary
replace transformer
• Defective voltage regulator board
(VRB) located inside front electri-
cal box • Confirm board produces 28VDC
present when the dispense button
is pressed (refer to the Electrical
Box Wiring Diagram for VDC out-
put location). Replace VRB if nec-
essary
PROBLEM PROBABLE CAUSE REMEDY