TL;DR: Replacing the Pentair 172855 3/4-inch stainless steel air vent strainer takes 10–15 minutes and requires minimal tools. This small screen prevents debris from clogging the air relief valve, ensuring proper air release from the filter system. Replacement restores proper air venting, prevents valve sticking, and maintains optimal filter performance. Signs needing replacement include slow air release, valve sticking, and visible debris accumulation.
SEO Summary: This 2026 guide provides complete step-by-step instructions for replacing Pentair 172855 3/4-inch stainless steel air vent strainer including tools, removal, installation, and testing procedures.
Related Categories
Table of Contents
Component Overview and Function
The Pentair 172855 3/4-inch stainless steel air vent strainer is a small but critical component protecting the air relief valve from debris.
Component Description:
- Part Number: Pentair 172855
- Size: 3/4-inch diameter
- Material: Stainless steel (corrosion-resistant)
- Type: Fine mesh screen strainer
- Location: Inside air relief valve assembly
- Function: Filters debris from air venting system
Function and Purpose:
- Prevents debris from entering air relief valve
- Protects valve mechanism from clogging
- Ensures smooth air release from filter
- Maintains proper valve operation
- Extends air relief valve lifespan
- Prevents valve sticking or jamming
Compatible Equipment:
- Pentair pool filters with air relief valves
- Sand filters (various models)
- DE filters (various models)
- Cartridge filters (select models)
- Works with universal high flow air relief valves
- Verify compatibility with your specific filter model
Why This Component Matters:
- Clogged strainer prevents proper air release
- Trapped air reduces filter efficiency 20–30%
- Blocked valve causes pressure buildup
- Debris in valve mechanism causes failure
- Small investment ($5–$15) prevents valve replacement ($30–$80)
Signs You Need Replacement
Recognizing failure symptoms helps maintain filter efficiency and prevents air-related problems.
Air Release Issues:
- Slow or incomplete air release when opening valve
- Air valve difficult to open or close
- Hissing sound but minimal air release
- Valve requires excessive force to operate
- Air trapped in filter (visible in sight glass)
- Pressure gauge reading higher than normal
Valve Operation Problems:
- Valve sticks in open or closed position
- Valve handle hard to turn
- Valve leaks water when closed
- Valve won't seal properly
- Grinding or gritty feel when operating
- Valve requires frequent cleaning
Visual Indicators:
- Visible debris on strainer screen
- Rust or corrosion on strainer
- Bent or damaged screen mesh
- Holes or tears in screen
- Heavy calcium buildup on strainer
- Strainer discolored or degraded
Performance Impact:
- Reduced filter efficiency
- Longer backwash cycles needed
- Cloudy water despite clean filter
- Increased pump run time required
- Higher energy consumption
- Premature filter media degradation
Tools and Materials Needed
Minimal tools required for this simple replacement task.
Required Tools:
- Adjustable wrench or pliers
- Small flathead screwdriver
- Clean rags or towels
- Small brush (old toothbrush works)
- Bucket for water drainage
- Safety glasses
Required Materials:
- Pentair 172855 3/4-inch stainless steel air vent strainer
- Teflon tape (optional, for threads)
- Clean water for rinsing
- Mild detergent or vinegar (for cleaning)
Optional But Recommended:
- Replacement air relief valve if damaged
- Silicone lubricant (pool-safe)
- Calcium remover solution
- Replacement air relief valve assembly if needed
- Spare O-rings for valve
Preparation and Safety
Proper preparation ensures safe, efficient replacement.
System Shutdown:
- Turn off pool pump at breaker
- Set multiport valve to "Closed" or "Winterize" position
- Release system pressure through air relief valve
- Verify pump completely off before proceeding
- Wait 2–3 minutes for system to fully depressurize
Pressure Release:
- Slowly open air relief valve
- Allow all air and water to escape
- Keep face and hands away from valve opening
- Have towel ready for water spray
- Ensure no pressure remains in system
Workspace Preparation:
- Clear area around filter
- Place bucket under valve for drainage
- Have all tools within reach
- Ensure adequate lighting
- Protect surrounding areas from water
Safety Considerations:
- Wear safety glasses (protect from water spray)
- Ensure system fully depressurized
- Avoid contact with pool chemicals on components
- Work carefully to prevent valve damage
- Keep children and pets away from work area
Removing Old Strainer
Careful removal prevents damage to air relief valve assembly.
Valve Disassembly:
- Locate air relief valve on top of filter
- Unscrew valve cap or knob (turn counterclockwise)
- Lift cap straight up carefully
- Set cap aside on clean surface
- Inspect valve interior for debris
Strainer Removal:
- Locate strainer screen inside valve body
- Note strainer orientation and position
- Carefully lift strainer straight out
- Use small screwdriver if stuck (gentle prying)
- Avoid scratching valve body interior
- Set old strainer aside for comparison
Inspection and Cleaning:
- Inspect valve body for damage or corrosion
- Check valve seat for debris or damage
- Clean valve interior with damp rag
- Remove calcium deposits with vinegar solution
- Rinse thoroughly with clean water
- Dry valve interior before installing new strainer
Old Strainer Inspection:
- Examine screen for holes or damage
- Check for heavy debris accumulation
- Note rust or corrosion level
- Compare with new strainer for size verification
- Determine cause of failure for prevention
Installing New Strainer
Proper installation ensures optimal air relief valve performance.
Strainer Preparation:
- Remove new strainer from packaging
- Inspect for shipping damage
- Verify correct size (3/4-inch)
- Compare with old strainer
- Rinse with clean water if needed
Installation Procedure:
- Position new strainer in valve body
- Ensure proper orientation (flat side down typically)
- Press strainer firmly into place
- Verify strainer seated completely
- Check that strainer doesn't block valve mechanism
- Ensure strainer sits flush in valve body
Valve Reassembly:
- Inspect valve cap O-ring for damage
- Lubricate O-ring lightly if needed
- Position valve cap over body
- Thread cap clockwise by hand
- Tighten snugly with wrench (don't over-tighten)
- Verify cap threads smoothly
Final Checks:
- Ensure valve cap fully seated
- Verify no cross-threading
- Check that valve operates smoothly
- Confirm strainer visible through valve opening
- Wipe exterior clean of fingerprints or debris
Testing and Verification
Thorough testing ensures proper installation and function.
System Startup:
- Restore power to pump
- Set multiport valve to "Filter" position
- Start pump and allow system to pressurize
- Monitor pressure gauge reading
- Listen for unusual sounds
Air Release Testing:
- Slowly open air relief valve
- Verify smooth air release
- Check for water spray (indicates air purged)
- Close valve when steady water stream appears
- Verify valve closes completely
- Check for leaks around valve cap
Operation Verification:
- Open and close valve several times
- Verify smooth operation without sticking
- Check that valve seals properly when closed
- Ensure no water leaks from valve
- Confirm normal pressure gauge reading
- Listen for proper air venting sound
Performance Checks:
- Verify filter pressure normal for clean filter
- Check water flow at return jets
- Ensure no air bubbles in return water
- Confirm pump maintains prime
- Monitor system for 10–15 minutes
- Recheck valve operation after initial run
Maintenance Tips
Regular maintenance extends strainer life and ensures optimal valve performance.
Cleaning Schedule:
- Inspect strainer every 3–6 months
- Clean during regular filter maintenance
- Check after heavy debris events (storms, high winds)
- Inspect if valve operation becomes difficult
- Clean more frequently in high-debris environments
Cleaning Procedure:
- Remove strainer following removal steps
- Rinse under running water
- Brush gently with soft brush
- Soak in vinegar solution for calcium removal
- Rinse thoroughly before reinstalling
- Dry completely if storing
Preventive Maintenance:
- Keep pool water chemistry balanced (prevents corrosion)
- Skim pool regularly (reduces debris load)
- Clean filter regularly (reduces system stress)
- Operate air relief valve monthly (prevents sticking)
- Inspect valve assembly during filter cleaning
- Replace strainer annually in harsh conditions
When to Replace vs Clean:
- Clean: Light debris, minor calcium buildup
- Replace: Rust, corrosion, holes, tears, heavy damage
- Replace: Strainer over 2–3 years old
- Replace: If cleaning doesn't restore function
- Keep spare strainer on hand for quick replacement
Conclusion and Key Takeaways
Replacing the Pentair 172855 3/4-inch stainless steel air vent strainer takes 10–15 minutes and requires minimal tools. This small screen protects the air relief valve from debris, ensuring proper air release from the filter system. Proper installation and regular maintenance prevent valve sticking, maintain filter efficiency, and extend valve lifespan.
Essential Takeaways:
- Air vent strainer prevents debris from clogging air relief valve
- Replace when clogged, damaged, or causing slow air release
- Turn off pump and depressurize system before starting
- Slowly open air relief valve to release pressure
- Unscrew valve cap to access strainer
- Lift old strainer straight out carefully
- Clean valve body interior before installing new strainer
- Position new strainer properly in valve body
- Press strainer firmly into place
- Reinstall valve cap hand-tight, then snug with wrench
- Test valve operation after installation
- Verify smooth air release and proper sealing
- Inspect and clean strainer every 3–6 months
- Replace annually in harsh conditions
- Use quality air relief valve assemblies for replacements
- Keep spare air relief valves on hand
- Maintain with complete valve gauge assemblies
- Consider upgrading to pressure relief valve assemblies for better performance
- Small investment ($5–$15) prevents valve replacement ($30–$80)
- Shop quality replacement parts from our pool parts collection
Follow these replacement steps for professional-quality results. Regular strainer maintenance ensures years of reliable air relief valve operation and optimal filter performance. The small investment in time and parts prevents costly valve replacement and maintains peak system efficiency.