TL;DR: Ideal pool skimmer winterizing: 1) Lower water level 4 to 6 inches below skimmer, 2) Remove skimmer basket and weir door, 3) Blow out skimmer line with air compressor (30 to 50 PSI), 4) Add 1 to 2 quarts pool antifreeze to skimmer, 5) Install winterizing plug in skimmer drain opening, 6) Install Gizzmo in skimmer throat ($5 to $15, absorbs expansion pressure). Gizzmo is essential freeze protection preventing skimmer damage costing $200 to $500 to repair. Never skip Gizzmo even in mild climates as unexpected freezes occur. Complete skimmer winterization takes 15 to 30 minutes per skimmer. Proper winterization prevents 99% of skimmer freeze damage.
SEO Summary: Complete 2026 guide to pool skimmer winterizing covering water level adjustment, basket and weir removal, line blowout procedures, antifreeze application, plug installation, Gizzmo selection and installation, inground vs above ground differences, freeze damage prevention, troubleshooting common issues, and spring opening procedures. Expert advice on proper techniques, product selection, avoiding mistakes, and ensuring complete skimmer protection throughout winter.
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Table of Contents
Why Skimmer Winterizing Matters
Skimmer winterizing is critical for preventing freeze damage that costs $200 to $500 or more to repair. Skimmers are particularly vulnerable to freeze damage because they hold water in confined spaces where ice expansion creates enormous pressure. This pressure cracks skimmer bodies, breaks fittings, and damages plumbing connections. Proper winterization prevents this damage through water removal and freeze protection devices.
Skimmer damage is among the most common and expensive winterization failures. A cracked skimmer body requires complete skimmer replacement involving excavation, plumbing work, and deck repair. This repair costs $500 to $2,000 depending on pool type and access difficulty. Damaged skimmer fittings or plumbing connections cost $200 to $800 to repair. These expenses are completely preventable through proper winterization costing $5 to $30 in supplies.
Freeze Damage Mechanisms
Water expands approximately 9% when freezing. In confined spaces like skimmers, this expansion creates pressure exceeding 25,000 PSI, far beyond what pool components can withstand. Rigid skimmer bodies cannot flex to accommodate expansion, causing cracks. Fittings and connections are stress points where cracks typically occur first.
Freeze damage often occurs during brief cold snaps rather than sustained winter cold. A single night of unexpected freezing can crack inadequately protected skimmers. This risk exists even in mild climates where pool owners may skip winterization thinking freezes are unlikely. Proper winterization protects against both expected and unexpected freezing.
Lower Water Level Properly
Lowering water level is the first and most important skimmer winterization step. Proper water level removes water from skimmer throat while maintaining adequate pool water for structure support. Incorrect water level either leaves skimmer vulnerable to freezing or exposes too much pool surface.
Lower water to 4 to 6 inches below skimmer opening. This level ensures skimmer throat is empty while keeping pool walls and floor submerged. Water above this level fills skimmer throat, creating freeze risk. Water significantly below this level exposes excessive pool surface and may not provide adequate structural support for some pool types.
The Taylor K 1000 Basic Residential Pool Test Kit ensures proper water chemistry before lowering water level for winterization.
Water Removal Methods
Use submersible pump to lower water level. Place pump in deep end and pump water to appropriate drainage location following local regulations. Monitor water level as it drops, turning off pump when desired level is reached. Lowering water typically takes 2 to 6 hours depending on pool size and pump capacity.
Alternatively, use pool's waste or drain setting if filter system has this option. This method is slower than submersible pump but requires no additional equipment. Monitor water level carefully to avoid lowering too much. Once water reaches proper level, switch filter back to normal operation for any remaining circulation needs.
Remove Basket and Weir
Removing skimmer basket and weir door prepares skimmer for winterization and prevents damage to these components. Baskets and weirs left in skimmers can trap water or be damaged by ice formation. Removal also provides access for blowing out skimmer line and installing winterizing devices.
Lift skimmer basket straight up and out of skimmer. Empty any debris and rinse basket clean. Inspect basket for cracks or damage, replacing if necessary. Store basket indoors in dry location protected from weather and rodents. Clean, dry storage extends basket life.
Weir Door Removal
Remove weir door by lifting it from hinge pins or unscrewing mounting screws depending on skimmer design. Some weirs simply lift out while others require removing fasteners. Consult skimmer manual if removal method is unclear. Forcing weir can break mounting points.
Clean weir door and inspect for damage. Weir springs should have good tension. Weir flap should move freely without binding. Replace worn or damaged weirs before next season. Store weir with basket in dry indoor location.
Blow Out Skimmer Line
Blowing out skimmer line removes water that could freeze and crack plumbing. This step is essential even if using antifreeze, as antifreeze works best in lines with minimal water. Proper blowout removes 90% to 95% of water from skimmer line.
Use shop vacuum or air compressor for blowout. Air compressor is more effective, providing higher pressure and volume. Set compressor to 30 to 50 PSI maximum. Higher pressure can damage plumbing. Connect air source to skimmer using appropriate adapter or simply hold air hose against skimmer opening.
Blowout Procedure
Close valves to other pool lines, directing all air flow through skimmer line. Apply air to skimmer, watching for water discharge from pool returns or main drain depending on plumbing configuration. Continue blowing until water stops flowing and only air comes out. This typically takes 2 to 5 minutes per skimmer line.
Some skimmers include blow out valves in Gizzmo or separate fittings. These valves allow air connection directly to skimmer line, improving blowout effectiveness. If your skimmer has blow out valve, use it for best results.
The Gizzmo Ultra Skimmer Freeze Protection with Blowout Valve 16 Inch includes integrated blow out valve for efficient line clearing.
Add Pool Antifreeze
Pool antifreeze provides additional freeze protection for water remaining in skimmer line after blowout. Antifreeze is non toxic propylene glycol safe for pool use. Never use automotive antifreeze, which is toxic. Add antifreeze after blowing out line for maximum effectiveness.
Pour 1 to 2 quarts antifreeze into skimmer. Antifreeze flows down skimmer line, mixing with residual water. This mixture has lower freezing point than water, preventing freeze damage. Use 1 quart for short skimmer lines (under 20 feet). Use 2 quarts for long lines (over 20 feet) or in areas with severe freezing.
Antifreeze Application Tips
Pour antifreeze slowly, allowing it to flow into line rather than splashing. Splashing wastes antifreeze and reduces protection. If possible, pour antifreeze through funnel for controlled application. Some pool owners add food coloring to antifreeze making it visible during spring opening, confirming it remained in line throughout winter.
Antifreeze is insurance against incomplete blowout or unexpected severe freezing. Even well blown out lines contain some residual water. Antifreeze protects this water, providing safety margin. The modest cost ($5 to $10 per gallon) is worthwhile for peace of mind.
Install Winterizing Plugs
Winterizing plugs seal skimmer drain opening at bottom of skimmer, preventing water from flowing back into blown out line. Plugs are essential for maintaining dry line throughout winter. Without plug, water can seep back into line, creating freeze risk.
Plugs come in various sizes and styles. Threaded plugs screw into drain opening, creating mechanical seal. Expansion plugs use rubber that expands when tightened, sealing non threaded openings. Identify your skimmer drain opening type and use appropriate plug. Most residential skimmers use 1.5 inch threaded plugs.
The Aladdin 1.5 Inch Rubber Fitting Pressure Test Plug 2 Pack provides reliable sealing for skimmer drain openings.
Plug Installation
Clean drain opening threads or surface before installing plug. Debris or algae prevents proper sealing. Apply plug hand tight. Do not overtighten as this can damage threads or crack plastic fittings. Plug should be snug but not forced.
Quality plugs include O rings or gaskets ensuring watertight seal. Inspect O ring before installation, replacing if worn or damaged. New O rings cost pennies and ensure reliable sealing. Worn O rings allow water seepage past plug, potentially causing freeze damage.
The The Winter Duck Plug Pool Closing Accessories provides quality winterizing plugs with reliable sealing.
Install Skimmer Gizzmo
Skimmer Gizzmo is the most important skimmer winterization device, providing freeze protection even if water remains in skimmer. Gizzmo absorbs ice expansion pressure, preventing damage to rigid skimmer body. This inexpensive device ($5 to $15) prevents expensive skimmer repairs ($200 to $500).
Gizzmo is hollow plastic tube that screws into skimmer throat. As water freezes, ice forms around and inside Gizzmo. The Gizzmo compresses as ice expands, absorbing pressure that would otherwise crack skimmer. This compression is Gizzmo's protective mechanism.
The Gizzmo Regular Skimmer Freeze Protection 9 Inch provides reliable freeze protection for standard residential skimmers.
Gizzmo Selection and Installation
Gizzmos come in standard and oversized versions. Standard Gizzmos (9 to 10 inches) fit most residential skimmers. Oversized Gizzmos (15 to 16 inches) fit commercial or large residential skimmers. Measure your skimmer throat depth or check skimmer model to determine correct size. Incorrect size does not provide proper protection.
Screw Gizzmo into skimmer threads, tightening hand tight. Do not overtighten as this can damage threads. Gizzmo should be snug but not forced. Gizzmo should extend from skimmer throat into skimmer body, positioned where ice formation occurs.
Never skip Gizzmo installation even if you completely drained skimmer. Unexpected water infiltration or precipitation can partially fill skimmer during winter. Gizzmo provides protection against these scenarios. The modest cost and simple installation make Gizzmo essential for every pool.
Inground vs Above Ground Skimmer Winterizing
Inground and above ground pools have different skimmer designs requiring slightly different winterization procedures. Understanding these differences ensures proper winterization for your specific pool type.
Inground Pool Skimmers
Inground skimmers are built into pool wall with plumbing running underground to equipment. These skimmers typically have drain opening at bottom connecting to main drain or return line. Winterization involves lowering water below skimmer, removing basket and weir, blowing out line, adding antifreeze, installing drain plug, and installing Gizzmo.
The SimPoolTech Winterizing Skimmer Plug for Inground Pool provides proper sealing for inground skimmer winterization.
Inground skimmers are more vulnerable to freeze damage because underground plumbing is difficult and expensive to repair. Thorough winterization is essential. Never skip steps or assume mild climate eliminates freeze risk.
Above Ground Pool Skimmers
Above ground skimmers hang on pool wall with short plumbing runs to equipment. These skimmers may not have drain openings, simplifying winterization. Procedure involves lowering water below skimmer, removing basket and weir, and installing Gizzmo or skimmer plug.
The Simpooltec Widemouth Above Ground Skimmer Plug provides freeze protection for above ground pool skimmers.
Some above ground pool owners remove skimmer entirely for winter, storing it indoors. This approach provides maximum protection but requires reinstallation in spring. If removing skimmer, plug wall opening to prevent debris infiltration.
Troubleshooting Common Skimmer Winterizing Issues
Even with proper procedures, issues can arise during skimmer winterization. Understanding common problems and solutions helps you address issues quickly, ensuring complete protection.
Water Won't Blow Out of Line
If water does not blow out of skimmer line, check valve positions ensuring skimmer line is open and other lines are closed. Verify air source has adequate pressure (30 to 50 PSI). Check for blockages in skimmer line including debris, closed valves, or collapsed hose.
Some skimmer lines have check valves preventing backflow. These valves also prevent air flow during blowout. If your system has check valves, you may need to remove them or use alternative blowout method. Consult pool professional if unable to blow out line.
Gizzmo Won't Fit
If Gizzmo does not fit skimmer threads, verify you have correct size. Standard Gizzmos fit most residential skimmers but some skimmers require oversized versions. Check skimmer model and order appropriate Gizzmo size.
If Gizzmo threads do not match skimmer threads, your skimmer may use different thread pattern. Some skimmers use fine threads while others use coarse threads. Order Gizzmo specifically designed for your skimmer brand and model.
Water Seeps Back Into Skimmer
If water seeps back into skimmer after winterization, check drain plug for proper sealing. Tighten plug or replace O ring if necessary. Verify plug is correct size for your drain opening. Undersized plugs do not seal properly.
Water seepage can also result from high water table pushing groundwater into skimmer through cracks or porous concrete. This issue requires professional assessment and repair. Temporary solution is to add extra antifreeze to skimmer, protecting against freezing despite water presence.
Conclusion: Complete Skimmer Protection
Proper skimmer winterizing prevents freeze damage costing $200 to $500 or more to repair. The systematic approach covering water level adjustment, basket and weir removal, line blowout, antifreeze addition, plug installation, and Gizzmo installation provides comprehensive protection. This protection requires 15 to 30 minutes per skimmer and costs $5 to $30 in supplies.
Water level adjustment is foundation of skimmer winterization. Lowering water 4 to 6 inches below skimmer removes water from skimmer throat, eliminating primary freeze risk. This step alone prevents most skimmer damage.
Removing basket and weir prepares skimmer for winterization and prevents damage to these components. Clean, dry storage extends their life and ensures they are ready for spring opening.
Blowing out skimmer line removes water that could freeze in plumbing. Use air compressor at 30 to 50 PSI for effective blowout. Continue until only air comes out, indicating line is clear.
Pool antifreeze provides insurance against incomplete blowout or unexpected severe freezing. Add 1 to 2 quarts per skimmer after blowing out line. This modest investment provides significant protection margin.
Winterizing plug seals drain opening, preventing water from flowing back into blown out line. Use correct size plug with good O ring for reliable sealing. Hand tighten without forcing.
Skimmer Gizzmo is essential freeze protection device that absorbs ice expansion pressure. Never skip Gizzmo installation regardless of climate or how thoroughly you drained skimmer. Gizzmo costs $5 to $15 and prevents damage costing hundreds to repair.
Understand differences between inground and above ground skimmer winterization. Inground skimmers require more thorough winterization due to underground plumbing. Above ground skimmers are simpler but still need proper protection.
Address winterization issues promptly. Water that won't blow out, Gizzmos that don't fit, or water seepage indicate problems requiring attention. Resolve issues before winter to ensure complete protection.
Document your skimmer winterization including procedures performed, products used, and any issues encountered. This documentation helps you refine procedures year after year and provides reference if problems occur.
Inspect skimmers in spring for freeze damage even if properly winterized. Unexpected issues or extreme weather can cause damage despite best efforts. Early detection allows prompt repair before damage worsens.
With proper skimmer winterizing following these ideal tips, your skimmers will survive winter without damage. Spring opening will involve simply removing Gizzmo and plug, reinstalling basket and weir, and raising water level. The time invested in proper winterization prevents expensive repairs and ensures trouble free spring opening.
The Swimline H2O Pro Pool Brush helps clean skimmer area during pre winterization preparation.
The HTH Ultimate Shock Treatment 6 Pack provides pre winterization shock treatment before skimmer winterization.
The In The Swim Pool Winterizing and Closing Chemical Kit provides complete winterization chemicals for comprehensive pool closing.
Explore our complete selection of skimmer winterizing supplies and accessories.
Key Takeaways:
- Lower water level 4 to 6 inches below skimmer removing water from throat
- Remove skimmer basket and weir door storing indoors in dry location
- Blow out skimmer line with air compressor at 30 to 50 PSI maximum
- Add 1 to 2 quarts pool antifreeze after blowing out line
- Install winterizing plug in drain opening with good O ring seal
- Install Gizzmo in skimmer throat costing $5 to $15 preventing $200 to $500 damage
- Never skip Gizzmo even in mild climates as unexpected freezes occur
- Standard Gizzmos (9 to 10 inches) fit most residential skimmers
- Oversized Gizzmos (15 to 16 inches) fit commercial or large skimmers
- Inground skimmers require thorough winterization due to underground plumbing
- Above ground skimmers have simpler winterization or can be removed entirely
- Complete skimmer winterization takes 15 to 30 minutes per skimmer
- Proper winterization prevents 99% of skimmer freeze damage
- Skimmer damage costs $200 to $2,000 to repair depending on severity
Remember that proper skimmer winterizing is essential for preventing expensive freeze damage. Follow these ideal tips systematically, use quality winterizing products including Gizzmo, and ensure complete protection for every skimmer. Your skimmers will survive winter without damage, spring opening will be straightforward, and you will avoid expensive repairs. Master skimmer winterization, and you master a critical aspect of pool ownership that protects your investment and ensures continued pool operation season after season.
