Annually; Maintenance Tasks; Inspection Methods - Trane Thermafit AXM Installation, Operation And Maintenance Manual

Modular air-to-water heat pump
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b. Verify refrigerant charge by recording the superheat
and sub-cooling temperatures.
c. Observe head pressure for signs of improper
condensing from clogged strainers, or a modulating
expansion valve issue.
12. Check compressor motor amperage draws and voltage
supplies and maintain a record of those values. Verify
that they are within the name plate rating. Also, check
for voltage imbalance. The heat pump's phase monitor
will open if the voltage imbalance exceeds 4%.
13. Check for chattering, excessive wear or burned
contacts. Replace contacts, if in doubt.

Annually

The annual heat pump maintenance inspection is critical to
the long-term performance of the system. Whether a heat
pump has a service life of 15 years or 30 years is almost
entirely dependent upon how consistently and how
diligently the annual maintenance inspection and tasks are
performed. The annual event is a comprehensive
inspection that examines all aspect of the heat pump to
identify and repair small problems before they can become
major issues that damage a heat pump and require
significant repair or refurbishment.
1. Inspect all electrical connections for damage and
confirm terminals are tight. Inspect all contactors for
pitting and corrosion and replace as necessary.
WARNING
Hazardous Voltage!
Failure to disconnect power before servicing could
result in death or serious injury.
Disconnect all electric power, including remote
disconnects before servicing. Follow proper lockout/
tagout procedures to ensure the power can not be
inadvertently energized. Verify that no power is
present with a voltmeter.
2. Inspect fuses to confirm they are secure, of correct
amperage rating, undamaged and functioning.
3. Energize each compressor and check refrigerant
pressures, signs of overheating, and oil leaks. Check
for noises and for leaks with an electronic or bubble
leak detector. Inspect flared fittings, refrigeration
gauges, compressor connections, braze joints,
pressure switches, and access ports on Schrader
valves.
ARTC-SVX009A-EN
WARNING
Refrigerant under High Pressure!
Failure to follow instructions below could result in an
explosion which could result in death or serious
injury or equipment damage.
System contains refrigerant under high pressure.
Recover refrigerant to relieve pressure before
opening the system. See unit nameplate for
refrigerant type. Do not use non-approved
refrigerants, refrigerant substitutes, or refrigerant
additives.
4. Follow proper "LOTO" procedures to de-energize each
module and inspect terminals for pitting, corrosion, and
loose connections.
5. Inspect that the oil level is visible in each compressor
and not discolored. Annual oil samples should be taken
to be analyzed for destructive acids, corrosive
materials, or metal deposits.
6. Inspect and record the compressor amperage draws
and voltage.
7. Record fluid mixture flow to confirm it meets design
specifications.
8. If equipped, tighten Rotalock fittings. The
recommended torque is 80 ft-lbs for 2 inch and larger
and 60 ft-lbs for Rotalock fittings smaller than 2 inches.
9. Inspect all copper lines and control capillary tubing to
confirm that the lines are separated and not vibrating
against one another or the frame or housing.
10. Confirm all refrigeration lines are properly supported to
prevent vibration from causing premature failure of
copper piping.
11. Inspect all insulation on piping and control sensors.
Repair and replace as necessary.
12. Inspect entire plumbing system for leaks.
13. Review logged alarms and look for repetitive trends.
14. If equipped, inspect crankcase heaters to verify proper
operation.
15. Sample refrigerant to analyze for moisture or acid.
16. Inspect operating pressures and temperatures and
confirm the heat pump has a full refrigerant charge.

Maintenance Tasks

The maintenance tasks described herein present the basic,
minimal, steps required to successfully complete a task.
Local policies and protocols may require more elaborate
procedures with additional checks and inspections.

Inspection Methods

Appropriate inspection for modern heat pumps can be
described as hands on. Where possible and appropriate,
inspection should include touching the component or
apparatus. The sense of touch provides additional
Maintenance Procedures
57

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