Winterize a Hot Tub in 5 Steps

Winterizing a spa is simple enough for the average spa owner to perform, with simple tools and equipment. Winterizing a wood hot tub? It is not recommended to drain a wood hot tub for an extended period, or else the wood will dry out and shrink.

To winterize a wood hot tub, you can follow the steps below, but then plug the lines and fill the hot tub back up with water.

To keep the water from freezing solid across a wood tub, use an air pillow like those used for above ground pool winterization, or fill several gallon sized plastic jugs, filled 1/3 full of pea gravel or non-toxic pool antifreeze. Float these in the hot tub to absorb ice expansion. Add spa algaecide or sanitizer to control algae growth and cover tightly.

To winterize a portable spa, one with an acrylic or fiberglass shell, follow these instructions:

1. Drain The Spa

You probably know this drill already, but in this case you need to get all of the water out of the spa - every drop. Open up the drain spigot and roll out the hose, or use a submersible pump (which is hours and hours faster). Shut off the power to the spa before draining and plan your drain - first by making sure the sanitizer level is low, and the pH is balanced. It's best to run the hose to an open yard, and move the hose often, to increase disbursement. In most cases, spa water is safe to use to water planter beds, trees or lawns, as long as your sanitizer level is under 1 ppm, and you move the hose around often.

2. Turn on the Blower

Once the water is drained out, you can turn on power to the hot tub, but keep the pumps and heater off. Activate the blower only, and unless you want a fine mist shower, put the spa cover over the tub first. After running the blower for a minute or less, allow the water to drain. If you have air jets in the seats or the floor, turn on the blower again and mop up the mist spraying out with a big towel. Wring out the towel and continue to wipe up any spray that continues to spit out from the small air holes.

3. Blow out the Pipes

This is the part that makes people nervous, but it's really quite easy. You'll need a large wet/dry vac, reversing the hose so that it blows air through the hose. Remove the skimmer basket and blow air through the skimmer, thru the filter, thru the pump, heater and back out through the spa jets. Be sure that all of the manual air intakes are open, and that all banks of jets are open. When all of the water has blown out, move the wet/dry vac inside of the spa, and blow air through the jets. You can also reverse the hose, and use suction to suck the water out. Be sure that all lines are open and all water has been removed.

4. Winterize the Spa Equipment

Remove the spa filter and give it a good deep cleaning, or dispose of it if it has been in service for more than 12 cleanings or 24 months. Open up the union nuts on the pump and heater, to check for any remaining water, and allow it to drain out. When tightening back up, make sure the union o-ring has not slipped out. Look over the system closely, and open any drain plugs that you see on the pipes or equipment, especially those on lower pipes. Keep the spa drain open, in case any water gets in during winter, and be sure to shut off all power to the spa, at the main circuit breaker.

5. Cover the Hot Tub

If your spa cover is not in the best of shape, invest in a cover cap, or tightly secure a tarpaulin over the spa, using bungee cords to keep it in place during high winds. If your spa cover is in good shape, it still would be a good idea to cover it, to protect the cover and to keep any rain or snow out of the spa. Another good thing to do during a spa closing is to clean and condition your spa cover, using one of our many spa cover care products.