split ac preventive maintenance checklist pdf

Standard Operating Procedure: Split System HVAC Preventive Maintenance

Document Control

• Document ID: SOP-HVAC-PM-[__________]
• Version: 1.0
• Effective Date: [__________]
• Review Cycle: Annual

1. Purpose & Scope

This procedure establishes the technical requirements for performing preventive maintenance on wall-mounted split-system air conditioning units. This document applies to all [Company Name] facilities to ensure optimal thermal efficiency, air quality, and equipment longevity.

2. Prerequisites

• Tools: Vacuum cleaner with HEPA filter, soft-bristle brush, fin comb, pressure sprayer (low PSI), non-acidic coil cleaner, screwdriver set, multimeter, flashlight.
• Materials: Replacement air filters, coil cleaning solution, condensate pan tablets, microfiber cloths.
• Access: Authorized site access, ladder/platform for indoor unit, roof/ground access for outdoor unit.

3. Roles & Responsibilities (RACI)

R=Responsible, A=Accountable, C=Consulted, I=Informed

4. Step-by-Step Procedure

Phase 1: Preparation and Safety

• Verify power supply is disconnected at the local isolator/breaker.
• Place drop cloths beneath the indoor unit to protect flooring.
• Inspect unit for visible damage or abnormal vibration history.

Phase 2: Indoor Unit Maintenance

• Remove and vacuum/wash return air filters.
• Inspect and clean the evaporator coil using a soft brush or specialized cleaner.
• Clear the condensate drain line; verify flow via the drain pan.
• Apply [__________] (brand/type) biocide tablet to the drain pan.
• Reassemble housing and wipe down exterior casing with a damp cloth.

Phase 3: Outdoor Unit Maintenance

• Clear vegetation and debris from a 24-inch perimeter around the condenser.
• Straighten bent fins using the fin comb tool.
• Clean condenser coils using low-pressure water (avoid high-pressure to prevent fin damage).
• Inspect electrical contactors and capacitors for signs of overheating or swelling.

Phase 4: Operational Testing

• Restore power to the system.
• Run system in "Cooling" mode for 15 minutes.
• Measure temperature differential (Delta T) between return air and supply air.
• Record findings: Supply Temp []°F / Return Temp []°F.

5. Quality Assurance, Pro-Tips, and Pitfalls

• QA: Verification of the Delta T (typically 15°F–20°F) is the primary indicator of system health.
• Pro-Tip: Always spray coil cleaner from the inside out (if accessible) to push debris out of the fins rather than deeper into them.
• Common Pitfall: Using high-pressure washers on aluminum fins will cause irreversible damage to the unit’s heat exchange capacity.

6. FAQs

Q: How often should this maintenance be performed? A: In standard environments, bi-annual maintenance is recommended. In high-dust or coastal environments, quarterly maintenance is required.

Q: What should I do if the system leaks water after cleaning? A: Ensure the condensate drain line is not kinked and that the drain pan is level. If the leak persists, check for cracks in the primary drain hose.

Q: Is it necessary to check refrigerant levels during every visit? A: No. If the Delta T is within the manufacturer's specified range, the refrigerant loop is likely sealed and should not be disturbed.