Table of Contents
Advertisement
Weekly
Weekly inspection is a continuation and elaboration of
daily best practice:
• Inspect touchscreen interface panel for alarm status
and additions to the alarm history. (Do not clear
alarms as this is a very important performance
record if troubleshooting problems arise.)
• Listen for excessive vibrations or motor noise. This
usually signals a loose brace or section of piping.
• Measure all refrigerant static pressure on any idle
circuits. Record any significant changes or
reductions in pressure.
• Clean strainers weekly during initial weeks after
initial start up until water quality has been reliably
established. Thereafter, inspect and clean strainers
at least monthly.
Monthly
The monthly maintenance inspection examines many
items that generally require frequent attention. This
routine event identifies small problems early before they
can become big problems requiring serious repair and
refurbishment:
1. Remove the strainer on the inlet water pipe to the
chiller/heater and verify that it is clean and free of
debris.
2. The 30 Mesh screen is made of SAE Grade 304
stainless steel. Clean the interior of the end cap (or
service cap), and the gasket using a soft natural bristle
brush and tap water. If fine particles cannot be
removed with the water stream, use a mild detergent
and a non-abrasive brush to remove them.
3. Check the compressor oil level sight glass. The oil
should always be clear and free-flowing. Any milky or
"slow rolling" effect indicates that liquid refrigerant is
making its way back into the compressor and will cause
premature compressor failure.
NOTICE
Equipment Damage!
Failure to remove moisture from system could cause
corrosion within the chiller/heater components and
degrade performance.
Perform vacuum evacuation of system to remove
moisture.
4. When the compressor is not operating, the oil level
should be at least at the bottom of the sight glass, up
to two-thirds full. When the compressor is operating,
the oil level will normally be at the bottom of the sight
glass, or even below, but it must be visible.
5. Low oil sight glass conditions could signify an
undercharged chiller that lacks proper refrigerant
velocity to return oil to the compressor sump.
ARTC-SVX005A-EN
Eventually, dry compressor starts could occur causing
premature compressor failure. This may indicate that
some oil has been lost from a previous refrigerant leak
repair. The compressor data label indicates the correct
oil type and quantity with which it should be filled.
Note: A flashlight may be required to see the oil churning
in the sump of the compressor. Adjusting the line of
sight may be necessary to visually inspect the oil in
the compressor sump during operation. At a
minimum, the oil must be seen churning in the
compressor sump. It should be clear.
CAUTION
Compressor Damage!
Failure to follow instructions below could result in
catastrophic compressor failure. Do not operate with
insufficient oil.
6. Check the glycol concentration using a refractometer.
NOTICE
Compressor Damage!
Failure to following instructions below could result in
extensive compressor damage.
Verify that suction pressure is sufficient. Secure the
circuit or module offline until status can be examined in
detail.
7. Check the refrigeration pressures.
8. For R410A refrigerant, low pressure refrigeration
gauge should read 120 to 160 psi and high pressure
refrigeration gauge should read 300 to 500 psi.
Important:
Suction pressures below 90 psi (R410A) is a
clear sign of insufficient refrigerant charge,
low water flow, refrigeration obstruction, or
valve closed units running only water.
9. For R134A refrigerant, low pressure refrigeration
gauge should read 35 to 50 psi and high pressure
refrigeration gauge should read 100 to 120 psi.
Important:
For R134A, suction pressures below 25 psi
can cause extensive damage to a
compressor.
10. Check the refrigeration liquid line sight glass for
persistent bubbles ('flashing') in conjunction with a
half-full glass may represent a low refrigerant charge.
NOTICE
Equipment Damage!
Failure to remove moisture from system could cause
corrosion within the chiller/heater components and
degrade performance.
Perform vacuum evacuation of system to remove
moisture.
Maintenance Procedures
57
Advertisement
Table of Contents
