RV-specific plumbing antifreeze is used to protect eligible fresh-water plumbing components when the RV is out of service. The correct method depends on water-heater design, filter housings, appliance branches and the manufacturer’s winterizing instructions.
Step-by-step guide
1. Identify the plumbing layout
Find the pump, fresh tank, low-point drains, water heater and any washer, icemaker, outdoor shower or toilet spray hose. Consult the RV manual.
2. Use only appropriate product
Choose antifreeze expressly labelled for RV potable-water plumbing and compatible with installed components. Automotive engine antifreeze is toxic and must never be used in drinking-water lines.
3. Isolate equipment as directed
Turn off energy to the water heater, allow it to cool, and follow the manufacturer’s draining and bypass instructions. Remove or bypass filter cartridges if required.
4. Protect every branch
Follow the manufacturer procedure to circulate or introduce the product through each applicable fixture and drain trap, including outside fixtures and appliance connections.
5. Verify and label
Check that all required outlets were addressed; note any components requiring separate procedures. Label the system as winterized and plan spring flushing and sanitization.
Common problems and what to check
| What you notice | Possible cause | Next step |
|---|---|---|
| One faucet runs clear | Branch may not have received protection | Recheck manufacturer flow path and bypass settings |
| Water heater full of antifreeze | Bypass not set correctly | Stop and review the heater and RV manuals |
| Unexpected pump cycling | Air leak or valve position | Inspect connections before storage |
Canadian winter considerations
Canadian winter lows vary widely; the product’s stated freeze/burst protection and the RV maker’s instructions matter more than a generic “winter rated” claim. Local wastewater rules govern disposal.
Check local forecasts, provincial road information and storage facility rules before you travel or work outdoors. Conditions vary widely between the Pacific coast, the Prairies, Atlantic Canada and the North.
Recordkeeping and follow-up
Save dated photographs, service receipts, product labels and inspection notes. Note any unresolved problems so they can be inspected before the RV returns to service. Where procedures involve gas, high-voltage electricity, structural repairs or vehicle lifting, use a qualified technician.
Useful Canadian resources
- Environment and Climate Change Canada — forecasts and alerts
- Government of Canada — emergency preparedness
- RV Storage Canada — facility directory (related directory)
Related winterizing guides
- RV Winter Storage Preparation Checklist
- RV Battery Storage in Canadian Winters
- Preventing RV Moisture and Mould in Storage
- Rodent and Pest Protection for Stored RVs
← All winterizing and storage guides
Choosing antifreeze
Use only non-toxic RV or marine antifreeze labelled for drinking-water plumbing. Check the burst-protection rating against the lowest temperatures in your region.
Step overview
- Drain the system and water heater.
- Bypass the water heater.
- Connect a pump intake hose or use the winterizing valve.
- Run each fixture until antifreeze appears.
- Pour some into each drain and the toilet.
Common mistakes
- Forgetting the outside shower or ice maker
- Using too little product
- Not bypassing the water heater
Frequently asked questions
How much antifreeze do I need?
Typically a few gallons, but it depends on the RV. Your manual may specify.
Does antifreeze need to be flushed in spring?
Yes. Flush thoroughly and sanitize before use.
Hands-on repair steps: see our complete RV winterizing guide.