How to Care for Your Hot Tub During Extreme Winter Weather

Severe winter weather can be tough on your hot tub—especially when temperatures drop below freezing or power outages interrupt circulation. Without proper preparation, freezing water inside plumbing and equipment can expand and cause cracked pipes, damaged pumps, or heater failure.

The good news? With the right plan, most freeze damage is preventable. At Valley Pool & Spa, we help homeowners protect their spas year-round. Below is a practical, step-by-step guide to caring for your hot tub before, during, and after extreme winter conditions.

Why Hot Tubs Freeze

Hot tubs are most vulnerable to freeze damage when water stops moving and temperatures remain below freezing long enough for ice to form inside plumbing lines. When water freezes, it expands—placing pressure on pipes, fittings, valves, pumps, filters, and heaters.

Contrary to popular belief, partially drained hot tubs can sometimes be at greater risk than full ones. Water left sitting in low spots or plumbing lines can freeze faster than circulating, heated water.

Before the Storm: Essential Hot Tub Prep Steps

Preparation is the most important part of winter hot tub care. Even if a storm is approaching quickly, taking a few proactive steps can significantly reduce the risk of damage.

1. Secure and Insulate the Cover

Your hot tub cover is the first line of defense against cold air. Make sure it fits snugly, seals completely, and is secured with straps or locks so wind can’t lift it. Avoid opening the cover during cold snaps—heat loss happens fast.

If snow is expected, gently remove heavy buildup using a soft broom to prevent the cover from becoming waterlogged or damaged.

2. Test and Balance Your Water

Cold weather doesn’t pause water chemistry needs. In fact, balanced water is easier to maintain during winter storms when outdoor access is limited.

Before severe weather arrives:

• Test and balance pH, alkalinity, and sanitizer levels
• Make sure you have enough sanitizer on hand
• Clean or rinse filters to ensure strong circulation

3. Confirm Circulation and Open All Jets

If your spa allows individual jet control, open all jet banks so water flows through every plumbing line. Moving water is far less likely to freeze than stagnant water.

4. Set Weather and Temperature Alerts

If your area experiences sudden temperature drops, enable weather or temperature alerts on your phone. Early warnings give you time to confirm the spa is heating and circulating properly before the coldest conditions arrive.

What to Do During Freezing Temperatures

1. Keep the Hot Tub Running

If power is available and the spa is operating normally, keep it running. Most modern hot tubs are designed to operate safely in winter as long as water is heated and circulating.

During extreme cold, running the circulation pump longer can further reduce freeze risk. If your spa has a freeze protection mode, confirm it’s enabled—many systems automatically activate circulation when temperatures approach freezing.

2. Keep the Cover Closed

Opening the hot tub releases valuable heat. During freezing conditions, keep the cover closed as much as possible to maintain water temperature and extend protection if weather worsens.

What to Do If the Power Goes Out

Power outages are the biggest winter risk for hot tubs because circulation stops. The goal during an outage is to retain as much heat as possible until power returns.

1. Raise the Water Temperature in Advance

If severe cold and outages are forecasted, increasing the water temperature slightly ahead of time can help the spa retain heat longer. A well-insulated hot tub with a sealed cover can often stay above freezing for short outages.

2. Keep the Cover Sealed

During an outage, resist the urge to check the water. Every time the cover is lifted, heat escapes and shortens the window of protection.

3. Use Extreme Caution with Cabinet Warming

Some professionals may recommend gentle cabinet warming during outages. However, improper use of heaters or electrical devices in wet environments can be dangerous. If you are not experienced with electrical safety, this is not a DIY step. When in doubt, contact a qualified spa service professional.

Dealing with a Frozen Hot Tub

If ice forms on the water surface or you suspect freezing in the plumbing, proceed carefully to avoid further damage.

1. Shut Off Power if Circulation Stops

If pumps cannot move water due to ice, turn off power at the breaker. Running frozen equipment can cause serious damage.

2. Thaw Slowly and Safely

Controlled thawing may include adding warm (not boiling) water to raise overall temperature and applying gentle, monitored heat in the equipment area. Avoid open flames or high-heat tools near plumbing, wiring, or insulation.

3. Inspect for Damage

As the spa warms, check for cracks, split fittings, broken unions, or leaking around pumps and heaters. Some condensation is normal, but steady water leaking from the cabinet often indicates freeze damage.

If damage is suspected, stop and call a professional technician.

When Winterizing Is the Better Option

In many climates, hot tubs can safely operate all winter with proper maintenance and reliable power. However, full winterization may be the safer choice if:

• Prolonged power outages are likely
• You’ll be away and unable to monitor conditions
• The spa already has circulation or heating issues
• Temperatures are expected to stay well below freezing for extended periods

Proper winterization involves fully draining the spa, removing water from plumbing and equipment, and clearing trapped moisture using specialized tools. Because incomplete winterization can still leave water behind, many homeowners choose professional winterization for peace of mind.

Severe Winter Weather Hot Tub Checklist

Before the storm:

• Secure and fasten the cover
• Remove heavy snow buildup
• Test and balance water chemistry
• Clean filters and confirm circulation
• Open all jets
• Set weather alerts

During freezing weather:

• Keep the spa running and full of water
• Keep the cover closed and latched
• Confirm freeze protection mode is active

If the power goes out:

• Keep the cover sealed
• Avoid opening the spa
• Contact a professional if unsure about safe warming options

If freezing begins:

• Shut off power if circulation stops
• Thaw slowly and inspect for damage
• Call a service technician if needed- Reach Valley’s service department HERE

We’re Here to Help

Your safety always comes first during severe winter weather. Once conditions improve, Valley Pool & Spa is here to help you get your hot tub back to peak performance. From water testing and chemical balancing to equipment inspections and winter service, our team is ready to keep your spa protected and running smoothly—so you can get back to relaxing, not repairing.

Need help preparing for winter or recovering after a storm? Contact Valley Pool & Spa today.