Test Your Freeze Protection Now — Not When the First Hard Freeze Hits

Water expands about 9% when it freezes, and when that happens inside a sealed pump body, filter chamber, or heater manifold, it cracks the housing. Nine percent sounds small. It is enough to split a pump in half. Every winter in Frisco we turn equipment back on after a freeze and water shoots out of cracked pump bodies, valves, and manifolds that were fine in November. The fix is not complicated: turn your freeze protection on now, test that it actually works, and know what to do when the power goes out — because that is when freeze protection stops protecting anything.

What Actually Breaks, and Why

Freeze damage is not gradual. It happens in a single cold night and you usually don't find out until you run the equipment.

When water sits still inside your equipment and the temperature drops below freezing, it turns to ice and expands. Because it has nowhere to go, the expansion pushes outward against whatever is holding it. Plastic and metal housings lose. What we find cracked, in rough order of frequency:

Pump bodies. The most common and most expensive. A cracked pump body can't hold prime, and epoxy patches generally don't hold on a cracked pump — it needs replacing.

Valves. The multiport and diverter valves on your pad hold standing water and crack the same way.

Heater manifolds and headers. Water gets trapped in the heater's headers, and that's where the leaks show up. Gas, electric, and solar heaters are all vulnerable.

Filter housings. Frozen water in the filter chamber splits the tank. A freeze-cracked filter is a pressure vessel with a fault line in it — it shouldn't be operated at all.

The plumbing itself. PVC on the pad and the pipes running to and from it.

The symptom is always the same. The pool sat through a cold snap, everything looked normal, and then the pump gets switched on and water sprays out of the pad. By then the damage is done — you're replacing parts, not preventing anything.

The 2021 statewide freeze destroyed entire equipment pads across Texas, and some of that damage was hidden: cracked underground plumbing, fractured tile and plaster, and internal component failures that showed no leak at first. Older equipment is more susceptible across the board.

The Defense Is Moving Water

Circulating water is the single most effective protection against freeze damage. Moving water is much harder to freeze than standing water, which is why running the pump through the coldest hours is the standard advice and why automation systems have a freeze protection setting at all.

Freeze protection mode does this automatically. When the air temperature drops to a set threshold, the system overrides your normal schedule and runs the pump to keep water moving. Most modern pools in Frisco have it.

Here's the problem: most homeowners assume it's on and set correctly, and plenty aren't. Automation gets reset after a power event, a board replacement, or a schedule change, and the freeze setting quietly goes back to default or off. Nobody notices in July.

So before winter, do three things:

1. Confirm freeze protection is enabled on your automation panel or timer.
2. Confirm the threshold is set sensibly — it needs to kick in before the air actually reaches freezing, not at 32°F exactly.
3. Test that it actually triggers the pump. Don't just look at the setting. Make sure the pump responds.

That last step is the one people skip, and it's the one that matters. A setting that's enabled on a screen but not actually driving the pump protects nothing.

The Gap Nobody Plans For: Power Outages

Freeze protection has one fatal dependency. It only works if the electricity stays on.

Power is the biggest wild card in any Texas freeze. Ice storms and grid strain take power down precisely during the coldest overnight hours — exactly when freeze protection needs to be running. The moment power drops, your pump stops, water goes still, and the clock starts. Even a brief outage during the coldest part of the night can be enough for water to freeze inside exposed pipes and housings. An outage lasting a day or more can freeze a pool solid.

This is the scenario that wrecks equipment pads, and no automation setting saves you from it.

What to do: if the power goes out during a freeze and your freeze protection can't run, the equipment needs to be manually winterized — water drained out of the pump, filter, heater, and lines so there's nothing left inside to expand. That's not a wait-and-see situation; it's time-sensitive. Call us and we'll come winterize the equipment before the damage happens. It's a fraction of what a cracked pump, filter, and heater manifold cost to replace.

Your Pre-Winter Checklist

Do these before the first hard freeze, not during one:

• Turn freeze protection on and verify the threshold setting
• Test it — confirm the pump actually starts when it should
• Clear the skimmer and baskets. A pump straining against a clogged basket moves less water, and fall leaf load clogs baskets fast
• Check your filter pressure. A dirty filter restricts flow, and restricted flow means less circulation when you need it most
• Know where your breakers are so you can confirm the pump is actually powered after an outage resets your schedules
• Insulate exposed plumbing on the pad where you can
• Have a plan for an outage — know who to call if power drops during a freeze

Why This Post Exists in October

Because freeze prep is worthless in January. By the time a cold front is on the forecast, the window for testing your automation and clearing your equipment has mostly closed, and every pool company in North Texas is booked solid. The homeowners who get through a Frisco winter without a cracked pump are the ones who checked their freeze protection in the fall, when it was a ten-minute job.

Nine percent expansion is all it takes. Check the setting now.

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Hydra Pool Services checks freeze protection as part of winter service across Frisco and 7 surrounding cities, and winterizes equipment when power outages leave pools exposed. Start your free 2-week trial →

Sources: Water expansion figure per the International Association for the Properties of Water and Steam, via Alpine Intel — Freeze Damage to Pool Equipment. Texas freeze equipment-failure patterns via Pool Magazine.