Key takeaways
- Winterizing means draining and protecting a tub you won't run all season. It's a different job than the routine upkeep on a tub you're keeping heated.
- The blowout step, clearing every line with a wet/dry vacuum, is what actually prevents the cracked pump housing that causes most winter damage.
- Non-toxic RV or marine antifreeze goes into the lines after the blowout, never into the tub itself, and only where air alone can't clear the plumbing.
- Skipping the cover and cabinet check after shutdown lets snow load and trapped moisture cause damage that has nothing to do with the water.
- Still deciding whether to shut the tub down for the season at all? That's a separate question, worth answering first.
If you've decided to shut your hot tub down for winter instead of running it through the cold, winterizing it properly is what keeps a cracked pump or a split line from turning into a spring repair bill. How to winterize a hot tub comes down to one goal: get every drop of water out of the plumbing before the first hard freeze hits Timmins. Here's the procedure done right, from the last soak to the cover going back on.
Not sure draining is even the right call for your situation? Drain It or Run It walks through that decision before you get to this guide.
How do you winterize a hot tub?
Drain the tub fully, then use a wet/dry vacuum to blow every line clear of water, starting at the pump and working through each jet and fitting. Remove the filter, open all unions and drain plugs, and add non-toxic antifreeze only to lines that can't be fully cleared by air. Leave the equipment compartment open to dry, then cover the tub.
The order matters more than any single step. Draining without blowing the lines leaves standing water in places gravity can't reach, and that's exactly where a freeze cracks a fitting. Blowing the lines without draining first just pushes air through water you haven't removed yet.
When should you winterize a hot tub in Northern Ontario?
Winterize before the first hard freeze, which around Timmins usually means having it done by mid to late October. Searches for winterizing peak in October at roughly 1,600 a month across Canada, which tracks with when daytime highs stop reliably climbing above freezing. Waiting until a cold snap has already hit raises the odds of standing water freezing before you get to it.
A mild stretch in early fall is the easiest window to work in. The tub is still warm enough to drain without the hose or lines icing up mid-job, and you're not racing a forecast to finish.
Step-by-step: the winterizing procedure
| Step | Tool | Time | If you skip it |
|---|---|---|---|
| Drain the tub completely | Garden hose or built-in drain valve | 30–60 min | Standing water freezes and expands, cracking the shell or plumbing |
| Remove and store the filter | By hand | 5 min | A wet filter left in place can freeze and crack |
| Blow out every line | Wet/dry shop vacuum | 20–30 min | Trapped water in jets and pipes freezes first, since it's isolated from airflow |
| Open unions, drain plugs, and low points | Wrench, by hand | 15 min | Pockets of water hide in fittings even after the lines are blown clear |
| Add non-toxic antifreeze to lines that can't fully drain | RV or marine antifreeze | 10 min | Any water left in a dead-end line has nowhere to expand |
| Leave the equipment bay open to air out | None | Overnight | Trapped moisture around electrical components risks corrosion over the season |
| Cover and secure the tub | Hot tub cover, clips | 10 min | An unsecured cover lets snow and moisture into the open cabinet |
Work through the list in order. Rushing the blowout step is the most common reason a tub that was "winterized" still ends up with a cracked pump housing by spring.
Where do you pour hot tub antifreeze, and what kind?
Pour non-toxic RV or marine antifreeze into the lines you've already blown clear with the vacuum, not into the tub shell itself. It belongs in any section of plumbing that can trap water even after blowing, such as a low loop in a pipe or a fitting the vacuum couldn't reach directly.
Use RV or marine antifreeze specifically, never automotive antifreeze. Automotive antifreeze contains ethylene glycol, which is toxic, and it has no place anywhere near a hot tub's plumbing. The RV and marine versions are propylene glycol based and safe if a trace is left behind.
Antifreeze isn't a substitute for blowing the lines. It's a backup for water you can't remove with air alone. If you're adding more than a small amount to more than one or two spots, that's usually a sign a line still has standing water in it somewhere upstream, and it's worth going back over the blowout step. If you need antifreeze or a replacement filter before you start, our chemicals and filters collection carries both.
What happens if you skip a step?
The most expensive mistake is skipping the blowout and assuming draining alone is enough. Gravity empties the tub shell, but it doesn't clear horizontal runs, jet bodies, or the pump housing, and that's exactly where a freeze splits plastic or cracks a seal. The second most common mistake is leaving the cover unsecured, which lets snow load sit directly on an open cabinet all winter.
Both mistakes tend to surface the same way: a fine-looking shutdown in October, and a leak or a dead pump the following April, once everyone has forgotten exactly what was or wasn't done in the fall.
FAQ
Can you winterize a hot tub without draining it?
No. Full winterizing requires draining the tub completely, since the entire point is removing water that could freeze and expand inside the plumbing. If you want to avoid draining, running the tub through winter is the alternative, not a partial winterizing.
Can you winterize a hot tub yourself?
Most owners can, with a wet/dry shop vacuum, non-toxic antifreeze, and about an hour. The steps aren't technical, but they're easy to rush. If your tub has a complex plumbing layout or you're not confident finding every low point, a technician can do it in less time than it takes to second-guess your own work.
How much does it cost to winterize a hot tub?
Doing it yourself costs mainly the antifreeze, typically a small one-time expense. Hiring it out costs more but adds the assurance that every line was actually cleared, which matters most if nobody will be checking on the tub over winter.
The bottom line
Winterizing a hot tub in Northern Ontario comes down to draining it completely, blowing every line clear, and giving the equipment bay time to dry before the cover goes back on. Do those three things properly and a shut-down tub survives a Timmins winter without a cracked pump waiting for you in spring.
Keeping the tub running instead? See what that actually costs before you decide. Either way, browse our chemicals and filters to have what you need on hand before the weather turns.
