U-Line UCBF632-SS12A User Guide & Service Manual

USER GUIDE
Troubleshooting
Troubleshooting
WARNING
!
Before performing any service that involves
electrical disconnection and/or exposure
to electrical components, always follow the
Electrical LOCKOUT/TAGOUT Procedure.
Disconnect all circuits. Failure to comply can
cause property damage, injury, or death.
Perform thorough troubleshooing if the cause of a problem
is not obvious. To test the internal components, unplug or
remove the unit from the power supply.
PROBES
The Blast Chiller is equipped with several temperature
sensing probes. These probes are Negative Temperature
Coecient (NTC) thermoset sensors (see Figure 1 and
Figure 2). The chamber and evaporator probes have the
same conguration. The Touch Screen version has a special
multicore needle probe (5 cores, but only 4 being read from
the board).
NTC Probe Bulb Probe Measuring
Figure 1: Room/Evaporator Probe Type
Figure 2: NTC Needle Probe Types
The needle probe has a dierent sensing element (see
Figure 3). Both types of probes have the same resistance
to temperature correlation.
Figure 3: Pt1000 Needle Probe Types (Multicore)
Checking the Probes
A Probe alarm occurs when something is wrong with the
sensor reading. The problem may be either the sensor
wires or the sensor itself. Probe alarms Er0, Er1, and Er3
are commonly due to an interrupted (open) circuit in the
wires.
Another cause may be a short to the chassis or the two
leads shorting together.
To nd the cause of the alarm, disconnect the indicated
probe and check the resistance between the two wires (or
between any of the 5 wires of a multiprobe type).
If the Ohm reading is 0 Probe circuit is
shorted between
the two wires
Replace the probe
Ohm reading is innity,
∞
Probe is open Replace the probe
Reading matches the
resistance chart at a
known temperature
Probe is good Another problem
is the cause
Reading is not 0 or ∞
and does not match the
resistance chart
Probe is out of
range
Replace the probe
If none of the choices is the issue: Ohm out each wire to
the chassis. If the reading is 0 or less than ∞, the probe is
shorted to the chassis and must be replaced.
NOTE: Use a spare probe instead of the suspected
one. If the alarm continues, the problem is
not the probe.
Search for additional Probe Alarm issues in the probe to
board terminal connection. Check for rust, water, humidity,
loosen/lost connections on the probe terminal block (see
Figure 4).
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U-Line UCBF632-SS12A Specifications

General

Brand	U-Line
Model	UCBF632-SS12A
Category	Freezer
Language	English