TestEquity 1007S, Operation And Service Manual

Page: 38 / 49

Chapter 8 – Maintenance
Page 8-10 TestEquity 1007S Temperature Chamber
SYMPTOM CONDITION CAUSES
Sightglass has bubbles or
does not look full.
1. During all running conditions.
2. Only when cool light is cycling.
1. Low charge (leak).
2. No problem. This is normal.
Cools too slow.
1. No bubbles in sightglass. 1. Chamber interior is overloaded.
Test sample is energized, giving
off heat. Port plug is not in port.
Cools all the time.
1. When cool light is OFF. 1. Solenoid valve SV1 may be
defective in open position.
Does not reach –35°C. 1. Sightglass looks full. Chamber
is empty.
1. Port plug is not in port. Door is
not sealing completely. Ice on
evaporator. Hot gas bypass
regulator may be defective or
set too high.
Temperature varies more
than ±0.5°C or 1°C total.
1. If tuning PID control parameters
in temperature controller were
changed.
2. If tuning PID control parameters
in temperature controller are as
shipped from TestEquity.
3. If tuning PID control parameters
in temperature controller are as
shipped from TestEquity and
only occurs in cool mode.
1. Re-enter values as shipped from
TestEquity.
2. Control parameters may need to
be changed for your unique test
conditions.
3. Solenoid valve SV1 may be
defective.
Compressors turn on and off
too frequently.
1. If compressor control
parameters in temperature
controller were changed.
2. If compressor control
parameters in temperature
controller are as shipped from
TestEquity.
1. Re-enter values as documented
in the temperature controller
manual.
2. Solenoid valve SV1 may be
defective.
Excessive noise and
vibration when the
compressor starts.
1. Chamber has been off for
several hours or more and is not
connected to source of power,
or main disconnect switch is off
during that time.
2. Chamber has been off for
several hours or more, and is
connected to source of power
and main disconnect switch is
on during that time.
1. The chamber must be connected
to the power source AND the
main disconnect switch must be
on for 3 hours prior to operating
the chamber.
2. Crankcase heater defective
(open).