TL;DR: Installing the Pentair 79126900 convertible fitting body takes 30–45 minutes and requires basic plumbing skills. This versatile fitting adapts between different pipe sizes and connection types, providing flexibility in pool plumbing configurations. Proper installation ensures leak-free connections, maintains optimal water flow, and allows easy equipment changes. Essential for pool equipment upgrades and repairs.
SEO Summary: This 2026 guide provides complete step-by-step instructions for installing Pentair 79126900 convertible fitting body including sizing, plumbing, and testing procedures.
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Table of Contents
Product Overview and Function
The Pentair 79126900 convertible fitting body is a versatile plumbing adapter that provides flexible connection options between different pipe sizes and equipment.
Product Description:
- Part Number: Pentair 79126900
- Type: Convertible fitting body/adapter
- Material: Durable PVC or CPVC (chemical-resistant)
- Connection Types: Multiple configurations available
- Sizes: Adapts between common pool plumbing sizes
- Function: Provides flexible connection options
Function and Purpose:
- Adapts between different pipe sizes
- Converts connection types (slip to threaded, etc.)
- Provides flexible plumbing configurations
- Enables equipment upgrades without replumbing
- Facilitates repairs and replacements
- Maintains optimal water flow
Key Features:
- Convertible design (multiple configurations)
- Durable construction for long life
- Chemical-resistant materials
- UV-stable for outdoor use
- Easy installation and removal
- Compatible with standard pool plumbing
Common Configurations:
- Slip to threaded adapter
- Size reducer (2-inch to 1.5-inch, etc.)
- Union connection adapter
- Equipment connection fitting
- Valve adapter
- Multi-purpose plumbing adapter
Common Applications
Understanding applications helps determine correct installation method.
Equipment Connections:
- Pump to filter connections
- Filter to heater connections
- Heater to return line connections
- Chlorinator connections
- Valve connections
- Works with Pentair filter and pump connectors
Pipe Size Transitions:
- 2-inch to 1.5-inch reductions
- 1.5-inch to 1-inch reductions
- Metric to standard conversions
- Equipment size mismatches
- Plumbing upgrades
Connection Type Conversions:
- Slip to threaded conversions
- Threaded to slip conversions
- Union to direct connections
- Flanged to slip connections
- Custom plumbing configurations
Repair and Replacement:
- Damaged fitting replacement
- Equipment upgrade installations
- Plumbing reconfiguration
- Leak repair
- System modifications
Tools and Materials Needed
Proper tools ensure efficient installation and prevent damage.
Required Tools:
- Hacksaw or PVC pipe cutter
- Measuring tape
- Sandpaper or deburring tool
- Adjustable wrench
- Screwdriver (if applicable)
- Clean rags or towels
- Bucket for water drainage
- Safety glasses
Required Materials:
- Pentair 79126900 convertible fitting body
- PVC primer and cement (if gluing)
- Teflon tape (for threaded connections)
- Replacement O-rings (if applicable)
- Silicone lubricant (pool-safe)
- Clean water for testing
Optional But Recommended:
- PVC pipe (if extending plumbing)
- Additional fittings (elbows, couplings)
- Pipe hangers or supports
- Pressure gauge for testing
- Quality connector replacements for above-ground pools
- Backup ball valves for isolation
Preparation and Safety
Proper preparation prevents mistakes and ensures safe installation.
System Shutdown:
- Turn off pool pump at breaker
- Close isolation valves if available
- Release system pressure through air relief valve
- Verify pump completely off before proceeding
- Wait for system to fully depressurize
Water Drainage:
- Place bucket under work area
- Open drain plugs or loosen connections
- Allow water to drain completely
- Have towels ready for residual water
- Ensure work area dry before starting
Workspace Preparation:
- Clear area around installation location
- Ensure adequate lighting
- Have all tools within reach
- Protect surrounding areas from PVC cement
- Ensure stable footing and access
Safety Considerations:
- Wear safety glasses (protect from PVC cement fumes)
- Work in well-ventilated area
- Avoid skin contact with PVC cement
- Keep children and pets away
- Have fire extinguisher nearby (PVC cement flammable)
Installation Procedure
Proper installation ensures leak-free connections and optimal performance.
Old Fitting Removal (if replacing):
- Cut out old fitting if glued in place
- Unscrew if threaded connection
- Remove union nut if union connection
- Clean pipe ends thoroughly
- Inspect pipes for damage
- Measure for new fitting placement
Pipe Preparation:
- Measure and mark pipe cut locations (if needed)
- Cut pipes square and perpendicular
- Deburr all cut ends with sandpaper
- Clean pipe ends with dry cloth
- Test-fit new fitting before gluing
- Verify correct orientation and alignment
Dry Fit Assembly:
- Assemble fitting without glue first
- Verify all connections align properly
- Check fitting orientation correct
- Ensure adequate clearance for operation
- Mark pipe and fitting alignment
- Disassemble for gluing
Gluing Procedure (if slip connection):
- Apply PVC primer to pipe ends and fitting sockets
- Allow primer to dry 10–15 seconds
- Apply PVC cement to both surfaces (generous coat)
- Insert pipe into fitting with twisting motion
- Align marks made during dry fit
- Hold for 30 seconds to ensure bond
- Wipe excess cement immediately
- Allow 2 hours minimum before pressure testing
Threaded Connection (if applicable):
- Apply 2–3 wraps of Teflon tape to male threads
- Wrap in clockwise direction (direction of installation)
- Thread fitting by hand until hand-tight
- Use wrench for final 1/4–1/2 turn only
- Don't over-tighten (can crack fitting)
- Verify connection secure and aligned
Union Connection (if applicable):
- Install fitting body in plumbing
- Lubricate O-ring with silicone lubricant
- Position union nut and O-ring
- Thread union nut hand-tight
- Use wrench for final 1/4 turn only
- Verify O-ring properly seated
Testing and Verification
Thorough testing ensures leak-free operation and proper function.
Visual Inspection:
- Verify fitting properly aligned
- Check all connections tight
- Inspect for visible cracks or damage
- Ensure no gaps in connections
- Verify proper orientation
Pressure Testing:
- Restore power to pump
- Open isolation valves slowly
- Start pump and pressurize system
- Check for leaks at all connections
- Monitor for 5–10 minutes under pressure
- Verify no water seepage
Leak Inspection Points:
- Glued joints (if applicable)
- Threaded connections (if applicable)
- Union connections (if applicable)
- O-ring seals
- Fitting body itself
Performance Verification:
- Verify normal water flow through fitting
- Check system pressure gauge reading
- Ensure pump maintains prime
- Listen for unusual noises
- Confirm no air leaks (bubbles in pump basket)
Final Checks:
- Tighten connections if minor seepage occurs
- Verify all tools and materials removed from area
- Clean up any spilled water or cement
- Document installation date for records
- Monitor connection over next 24 hours
Troubleshooting Common Issues
Addressing problems quickly prevents system damage and water waste.
Leaks at Connections:
- Cause: Insufficient PVC cement applied
- Solution: Cut out joint, redo with proper cement
- Cause: Joint moved during curing
- Solution: Cut out and redo with proper hold time
- Cause: Dirty or wet surfaces during gluing
- Solution: Cut out, clean properly, reinstall
- Cause: Threaded connection not tight enough
- Solution: Tighten additional 1/4 turn with wrench
Fitting Won't Align:
- Cause: Pipes not cut square
- Solution: Recut pipes perpendicular
- Cause: Wrong size fitting
- Solution: Verify sizes, replace with correct fitting
- Cause: Plumbing misaligned
- Solution: Adjust plumbing or use flexible coupling
Reduced Water Flow:
- Cause: Fitting undersized for application
- Solution: Replace with larger fitting
- Cause: Debris in fitting
- Solution: Flush system, clean fitting
- Cause: Fitting installed backwards
- Solution: Verify orientation, reinstall if needed
Cracked Fitting:
- Cause: Over-tightened threaded connection
- Solution: Replace fitting, tighten properly
- Cause: Excessive stress from plumbing
- Solution: Support plumbing, reduce stress on fitting
- Cause: Freezing damage
- Solution: Replace fitting, winterize properly
Maintenance Tips
Regular maintenance extends fitting life and ensures reliable operation.
Periodic Inspection:
- Check connections every 3–6 months
- Inspect during routine pool maintenance
- Verify no leaks or seepage
- Check for cracks or damage
- Monitor for any changes in performance
Preventive Measures:
- Maintain proper water chemistry (prevents corrosion)
- Don't over-tighten threaded connections
- Support plumbing to reduce stress on fittings
- Protect from freezing in cold climates
- Inspect after any plumbing work
When to Replace:
- Visible cracks or damage
- Persistent leaks despite repairs
- UV degradation (brittle, chalky appearance)
- Chemical damage (discoloration, pitting)
- Fitting over 10–15 years old
- During equipment upgrades
Conclusion and Key Takeaways
Installing the Pentair 79126900 convertible fitting body takes 30–45 minutes and provides flexible connection options for pool plumbing. This versatile adapter enables equipment upgrades, repairs, and custom plumbing configurations without extensive replumbing. Proper installation with correct sizing and technique ensures years of leak-free, reliable operation.
Essential Takeaways:
- Convertible fitting adapts between pipe sizes and connection types
- Essential for equipment upgrades and repairs
- Turn off pump and drain water before starting
- Measure carefully to ensure correct sizing
- Test-fit before gluing to verify alignment
- Apply PVC primer and cement to both surfaces
- Insert pipe with twisting motion for even cement distribution
- Hold joint for 30 seconds to ensure proper bond
- Use Teflon tape on threaded connections (2–3 wraps)
- Hand-tighten threaded connections, then 1/4–1/2 turn with wrench
- Lubricate O-rings before installing union connections
- Allow 2 hours minimum before pressure testing
- Test under pressure for 5–10 minutes before leaving
- Monitor for leaks at all connection points
- Don't over-tighten connections (causes cracks)
- Use quality universal wall fittings for pool cleaners
- Maintain with replacement O-rings for pumps and filters
- Install ball valves for isolation and service
- Proper installation prevents $100–$300 in leak damage
- Shop quality plumbing parts from our pool parts collection
Follow these installation steps systematically for professional-quality results. Proper convertible fitting installation provides flexible plumbing solutions and enables easy equipment changes without extensive replumbing. The investment in quality fittings and proper installation ensures years of leak-free operation and system reliability.
