Compu-aire System 2100 Series Installation And Operation Manual page 40

Complaint
Complaint
4. Sensor(s) do not
adjust into range.
5. System does not cool
or does not cool
sufficiently.
Wiring to sensor circuit
board(s) are loose or
broken.
Problem
Problem
Circuits on MCP are out
of calibration.
Control parameters are
not set correctly or are
Display shows very high
or low values or values
that change erratically.
Symptom
Symptom
Displayed values change
but, adjustments to the
sensor circuit board do
not bring the
temperature or
humidity dis-played to
the actual value.
System seems to
function okay
otherwise.
40
recalibrating the sensor
circuits (see the section
MCP Circuit
Adjustment, in this
guide).
Check all wiring
between the sensor
circuit board and the
MCP for loose
connections. If the
values
Action
don't change and they
seem to be at an
extreme high or low,
test for 24-VAC at the
sensor board. Test for
continuity be-tween
Temp and Hum on the
sensor board and pins 9,
14, and 16 on the MCP.
If tests fail repair or
replace wiring to sensor
boards. If tests are okay,
swap connections
between pins 14 and 16
and observe whether
dis-play tracks each
okay. If it does, replace
the sensor. If it doesn't,
.
replace the MCP
Action
See the section,
Adjusting MCP Circuits
in this guide. If those
adjustments fail and
instructions for item 3
above have been
followed, contact
Compu-Aire for further
assistance.
Refer to the section in
this guide, Environment
Control Settings, and