How to Winterize Your Chinook B+ Motorhome
- SavvieTeam
- Nov 20
- 4 min read
Updated: Nov 21
As temperatures drop, it’s essential to protect your Class B+ motorhome from freezing conditions.
Winterizing your RV keeps your plumbing system safe, prevents costly repairs, and ensures your Chinook is ready to roll when warmer weather returns.
In the video below, Chinook RV National Sales Manager Seth Buchheit walks you through the exact steps to winterize your Chinook B+ motorhome equipped with the Timberline System. Whether you're a new owner or just need a refresher, this guide gives you everything you need to confidently winterize your RV.
Step-by-Step: How to Winterize Your Chinook B+ Motorhome
Below is a full written walkthrough of the winterization process demonstrated in the video.
Turn On Your RV's Power
Start by ensuring your motorhome has power:
Hit the battery disconnect switch
Confirm power is active before proceeding
Drain the Fresh Water Tank
Inside your RV:
Open up the dinette to access the fresh water tank valve.
Turn the valve to begin draining the tank completely.
Once empty, close the valve before moving on.
Turn On the Water Pump and Clear the Water Lines
With the fresh tank drained:
Turn on your water pump
Open each faucet (kitchen, bathroom sink, shower) to remove remaining water
Don’t forget the outside shower, a commonly missed step
When complete, shut off the water pump
Drain the Low-Point Drains
Go to your RV’s low-point drains and empty them fully. Once drained, close them securely.
Set Your Valves for Winterization
Inside your water control panel:
Flip the first diverter to City Water
Flip the second diverter to Winterize
This reroutes the system for drawing antifreeze instead of fresh water.
Connect Your RV Antifreeze Hose
Insert your garden hose into your jug of RV-safe antifreeze
Connect the opposite end to the winterization port
Head back inside your RV
Shut Off the Fresh Tank Line & Open the Antifreeze Valve
Depending on your model:
SS Model: This valve is under the sink
DS Model: This valve is under the sofa
Flip the valve to shut off the fresh tank, then open the valve for antifreeze flow.
Run Antifreeze Through All Water Lines
Turn the water pump back on and run antifreeze through:
Kitchen faucet (hot and cold)
Bathroom faucet (hot and cold)
Toilet — flush until you see pink antifreeze
Outside shower (both lines)
Winterize the Low-Point Drains
Once all fixtures show antifreeze, pull the low-point drains one more time to ensure antifreeze has reached them. Turn off the water pump when finished.
Want to see each step in action? Watch Seth’s full walkthrough on winterizing your Chinook B+ motorhome with the Timberline system. His straightforward demonstration makes the process easy, even for first-time RV owners.
Chinook RV Winterization FAQs
Below are answers to the most common questions we hear from Chinook RV owners when it comes to winterization.
When should I winterize my Chinook RV?
Winterization should be done before temperatures consistently drop below 32°F (0°C). Even a single overnight freeze can cause damage to your plumbing system.
How much RV antifreeze does a Chinook B+ motorhome need?
Most Chinook owners use 1–2 gallons of RV-safe pink antifreeze. Using more is always better than not enough, especially if you’re unfamiliar with the process.
Do I need to drain my hot water heater?
Chinook B+ models equipped with the Timberline system do not use a traditional hot water heater. The Timberline hydronic system simplifies winterization by removing the need for a tank drain or bypass.
Can I winterize using compressed air instead of antifreeze?
We don’t recommend using compressed air alone. While it helps remove water, it may not fully protect small fittings or valves. The safest method is antifreeze-only or compressed air + antifreeze.
Should I run the Timberline system after winterizing?
No. Once your lines are filled with antifreeze, avoid running the hydronic heat or hot water modes until de-winterizing in spring.
Can I drive my RV after it has been winterized?
Absolutely. Winterization affects your water system, not your drivability. You can still travel, camp, and use all non-plumbing features.
What if I store my RV in a heated garage, do I still need to winterize?
If your garage stays above 40°F at all times, winterization may not be necessary. But most owners still choose to winterize as a safeguard in case of power outages or unexpected temperature drops.
Do I need to winterize my 4-season certified Chinook B+ motorhome?
Yes, if your RV will be stored in freezing temperatures, winterization is still necessary. A 4-season rating helps keep you comfortable while using the coach in cold weather, but it doesn’t protect the plumbing when the motorhome is powered off and sitting in storage. Winterizing ensures your water lines and fittings stay safe during long periods of downtime.
What does “4-season certified” actually mean?
A 4-season motorhome is built with enhanced insulation, heated and enclosed tanks, insulated or dual-pane windows, and an efficient heating system. These features help maintain warmth and protect key components during cold-weather use. However, they don’t replace the need for proper winterization before long-term storage.
What happens if I skip winterizing a 4-season certified RV?
Even in a 4-season certified coach, freezing temperatures can cause water lines to burst, fittings to crack, or pumps to fail. Winterization is the best way to avoid costly plumbing repairs and protect your RV during cold-weather storage.
Want to learn more? Explore our library of Chinook RV how-to videos and get step-by-step gudiance to keep your coach in top condition year-round.