WinterProof Plumbing Antifreeze -50°C | 9.46 L | 063-9925-6
Free returns on all eligible orders
You have 30 days to request a return. All sale items are final sale.
WinterProof Plumbing Antifreeze — -50°C | 9.46 L | 063-9925-6
Part Number: 063-9925-6 | Brand: WinterProof
WinterProof 063-9925-6 is a ready-to-use -50°C / -58°F plumbing and water-system antifreeze in a 9.46 L (2.5 US gal.) jug. It is formulated to protect water lines, plumbing, pumps, valves, and seals from freeze damage during seasonal storage.
The formula is safe for both metal and plastic plumbing and helps prevent rust and corrosion while lubricating waterlines, pipes, and seals.
Important: This product is for water and plumbing systems only. It is not an engine coolant and is not a replacement for closed-loop engine cooling system antifreeze.
Specifications
- Part Number: 063-9925-6
- Brand: WinterProof
- Product Type: Plumbing / Water System Antifreeze
- Freeze Protection: -50°C / -58°F
- Container Size: 9.46 L / 2.5 US gal.
- Formula: Ready-to-use (no dilution required)
- Compatible Materials: Metal and plastic pipes and fittings
- Weight: approx. 9.5 kg / 21 lb (full jug)
Intended Applications
Designed for seasonal winterization of water and plumbing systems. Suitable for:
- Marine freshwater systems — tanks, lines, pumps, faucets, water heaters, and holding tanks
- RVs and camper trailers
- Cottages, cabins, and seasonal dwellings
- Swimming pools and hot tubs
- Any seasonal plumbing system requiring freeze protection
SKU Identification Note
WinterProof produces several antifreeze products with similar names — confirm the correct SKU for your application before ordering:
- 063-9925-6 — Plumbing Antifreeze, -50°C, 9.46 L (this product)
- 063-9910-0 — RV Antifreeze, -50°C, 3.78 L (different product)
- 063-9922-2 — Marine Water System Antifreeze, -50°C, 3.78 L (different product)
Before You Winterize
Follow the winterization procedure specified by the boat, RV, or plumbing system manufacturer. Before introducing antifreeze:
- Drain as much water as practical from all tanks, lines, pumps, and fixtures
- Water left in the system will dilute the antifreeze and reduce freeze protection
- Confirm compatibility with any installed water heaters, inline filters, treatment systems, or UV sterilizers before circulating the product through them
When to Use Fresh Antifreeze
- The water system has been drained for winter storage
- Previously introduced antifreeze has been flushed out
- The system has been refilled with water during the off-season
- Existing antifreeze has become diluted by residual water
- Plumbing repairs have introduced additional water to the system
- The winterization status of the system is unknown or unverified
Winterization Procedure (General)
- Drain freshwater tanks and pressurized lines to remove standing water
- Introduce antifreeze into the system and circulate until protected fluid reaches every faucet, pump, valve, and low point
- Pay close attention to locations where water may remain trapped — pumps, foot valves, water heater drain plugs, and low runs of hose are common problem spots on boats
- When returning the system to service in spring, flush the plumbing thoroughly before use, per the antifreeze manufacturer’s instructions
Cross-Reference
- WinterProof: 063-9925-6
- Also referenced as: 063-9925
Parts Desk Insights
Best use case: The 9.46 L jug is the right size for most boat freshwater systems — it provides enough volume to fully circulate through tanks, lines, and all fixtures without running short on a typical cruising-size vessel. The -50°C rating gives a meaningful safety margin over the -40°C products common on shelves, which matters in a cold snap or if some dilution from residual water is unavoidable.
Common issues: The most frequent winterization mistake is draining the main freshwater tank and assuming the job is done — pumps, water heaters, foot valves, and low spots in the plumbing almost always retain water and will freeze if antifreeze doesn’t reach them. Circulate until you see antifreeze coming out of every tap and fixture. Also confirm you have the right product — this 9.46 L plumbing antifreeze (063-9925-6) is a different SKU from the 3.78 L marine water system antifreeze (063-9922-2) and the 3.78 L RV antifreeze (063-9910-0).
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 1-3 business days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
To qualify for a return:
Item must be in new, unused condition
Product must be in its original packaging
All parts, components, hardware, manuals, and accessories must be included
Packaging must be undamaged and suitable for resale
Important:
Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.
We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.
For return authorization, please contact our support team before shipping anything back.