Compressor & Filter Drier Replacement
Step-by-step field checklist for split system compressor replacement
Split System — Compressor & Filter Drier
Complete each step in order. Flag any item that needs follow-up or has an abnormal finding.
1. Pre-Work Verification
Confirm Compressor Failure
Verify compressor is failed — check amps, megohm test windings, listen for locked rotor or open windings
Verify Replacement Compressor & Filter Drier
Confirm replacement compressor matches tonnage, voltage, and refrigerant type. Verify filter drier is correct for the system
EPA 608 Certification & Refrigerant Handling
Confirm certified tech is on-site for refrigerant recovery. Verify recovery machine and tanks are ready
Disconnect & Lock Out / Tag Out
Turn off disconnect, shut off breaker, and verify unit is de-energized before starting work
2. Refrigerant Recovery
Recover Refrigerant
Connect recovery machine to service ports and recover all refrigerant from system into recovery cylinder
Oil Acid Test
Pull oil sample from old compressor and test for acid — determines if system flush is needed before new compressor install
3. Removal
Braze Off Old Compressor & Filter Drier
Using nitrogen purge, braze off suction and discharge lines from old compressor. Remove old filter drier
Remove Old Compressor
Unbolt compressor from mounting pad, remove vibration grommets if worn, and set aside for disposal
System Flush (if acid present)
If acid test shows contamination, flush line set and evaporator coil with approved flush solvent before installing new compressor
4. Installation
Set & Mount New Compressor
Position new compressor on pad, install new vibration grommets, and bolt down securely
Install New Filter Drier
Braze in new filter drier in the liquid line, arrow pointing toward TXV/metering device. Do not leave open to atmosphere longer than necessary
Braze Suction & Discharge Lines
Braze suction and discharge connections on new compressor with nitrogen flowing. Inspect all joints for silver braze penetration
Wire New Compressor
Connect compressor terminals per wiring diagram — verify common, run, and start terminals. Reinstall start capacitor and contactor wiring
5. Pressure Test, Evacuation & Recharge
Pressure Test with Nitrogen
Pressurize system to 150–200 psig with dry nitrogen and leak check all new braze joints and connections
Triple Evacuation
Evacuate system to 300 microns or lower. Pull vacuum, break with nitrogen, re-evacuate — repeat 3 times for deep moisture removal
Recharge Refrigerant
Weigh in refrigerant to nameplate charge or per superheat/subcooling method. Document weight charged
System Start & Runtime Check
Energize system, observe startup, and verify normal operation — amps, pressures, temperatures, and delta T
6. Documentation & Close-Out
Photo Documentation
Photograph failed compressor nameplate, new compressor nameplate, braze joints, filter drier, and gauges at startup
Warranty Registration
Register new compressor warranty with manufacturer if required. Note serial number and install date
Job Notes & Customer Sign-Off
Document refrigerant recovered, refrigerant recharged, parts installed, and any additional findings. Obtain customer signature
Note: Always flow nitrogen during brazing to prevent copper oxidation and contamination of the new compressor. Never install a new compressor into a system with acid contamination without flushing first.
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