Pools in Austin do not get closed for winter the way pools in Ohio do. Ours run year-round, which is one of the pleasures of owning one here — and also the reason a hard freeze does so much damage locally.
A pool built for a mild climate has exposed above-ground plumbing, equipment pads open to the air, and no winterization routine. When temperatures drop into the teens for several consecutive days, as they have repeatedly over the past several winters, that setup fails. Cracked pump housings, split filter tanks, burst PVC, and ruined heaters are common outcomes, and the repair calls arrive all at once when every pool company in the region is booked.
The damage is largely preventable. Here is what actually works.
Why Freezes Break Pools Here Specifically
Water expands roughly nine percent when it freezes. In a sealed pipe or a pump housing, that expansion has nowhere to go, and something has to give.
Moving water is far more resistant to freezing than still water. That single fact drives almost all correct freeze protection advice: the goal is to keep water circulating, not to shut everything down.
The failures we see most often are equipment left off during a freeze, plumbing above the waterline that had no protection, filters left full of standing water after being shut down, and — the one that catches almost everyone — a power outage that stopped circulation while the owner assumed the pump was running.
Before a Freeze: What to Do
Run the pump continuously. Once temperatures are forecast to drop below about 32 degrees, take the pump off its timer and run it around the clock until the freeze passes. This is the single most important step. The electricity cost of running a pump for two or three days is trivial compared to a cracked pump housing.
Run every feature, not just the main circuit. Spa lines, waterfalls, spillways, cleaner lines, and in-floor systems each have their own plumbing. Water sitting still in a spa line freezes just as readily as anywhere else. If you have automation, set it to cycle features periodically.
Do not drain the pool. This is a serious and surprisingly common mistake. Water in the pool is what counterbalances groundwater pressure beneath the shell. A drained pool in saturated Central Texas clay can float, crack, or shift. Keep it full — a full pool also freezes far more slowly than a partially drained one.
Insulate exposed plumbing and equipment. Pipe insulation, foam covers on exposed fittings, and a blanket or insulated cover over the pump and filter all help meaningfully. Leave adequate ventilation around any heater.
Check your freeze protection setting. Most modern automation systems include a freeze protect mode that starts circulation automatically at a set temperature. Confirm it is enabled and that the sensor is functioning before winter, not during it.
Keep the water level normal. Skimmers with low water pull air and lose prime, which stops circulation exactly when you need it.
What Actually Breaks, and What It Costs
Understanding which components are vulnerable helps you prioritize when a freeze is hours away and you only have time to do a few things.
The pump is usually first to fail and the most expensive single item on the pad. Water trapped in the volute expands and cracks the housing, and a cracked housing is not repairable — the pump gets replaced. Variable-speed pumps, now standard on most newer installations, cost considerably more than the single-speed units they replaced.
Filter tanks split along the band or at the base when full of standing water. Cartridge and DE filters are both vulnerable.
Heaters are the most sensitive item on the pad. The internal heat exchanger has thin copper tubing that ruptures easily, and a ruptured exchanger frequently means replacing the heater rather than repairing it.
Above-ground PVC cracks and splits, particularly at fittings and unions where the wall is thinnest. This damage is at least visible and comparatively inexpensive to fix.
Underground plumbing is the quiet one. Buried lines are somewhat insulated by soil, but shallow runs and lines under decking do freeze. These cracks produce slow leaks that surface weeks later as unexplained water loss.
Salt cells, sensors, and automation contain water in small passages and are easily damaged.
Set against those numbers, running the pump continuously for three days is not a difficult decision.
Freezes Are Hard on the Shell and Finish Too
Equipment gets most of the attention, but the pool structure takes stress as well.
Water that has worked into existing hairline cracks in plaster expands when it freezes, widening those cracks incrementally each time. Over several hard winters, minor crazing can progress into something that requires patching or resurfacing. The same process affects tile grout and the mastic joint between coping and deck, which is exactly where water most easily gets behind the shell.
This is one reason small finish problems are worth addressing before winter rather than after. A crack that is sealed cannot collect water, and water that cannot collect cannot freeze and pry.
Central Texas adds a second factor. Our soil is already moving seasonally with wet and dry cycles, and freeze-thaw activity in saturated clay adds another kind of movement. A pool that already shows signs of soil-related stress deserves a look before a hard winter rather than during one.
If the Power Goes Out
This is where most Central Texas freeze damage originates, because circulation stops and no one realizes it.
If you lose power during a hard freeze, shut off the pump at the breaker so it does not restart against frozen plumbing. Open the drain plugs on the pump and filter to let water out of the housings, and remove the pump basket lid. Open air relief valves. Set the valves so any remaining water can drain rather than being trapped.
Emptying the equipment is far better than leaving it full and hoping. A pump housing full of standing water at 18 degrees will crack.
What Not to Do
Never add automotive antifreeze to pool plumbing — it is toxic and will contaminate the pool. Never run a pump dry to “clear the lines,” which destroys the seal within minutes. Do not pour hot water on frozen pipes or equipment, since thermal shock cracks PVC and can crack a pump housing outright. And do not break ice on the surface of the pool with anything hard; the impact can damage the finish, and surface ice is not itself the threat.
After the Freeze: Finding the Damage
Damage frequently does not announce itself. Plumbing can crack underground and only reveal itself later as gradual water loss.
Once temperatures recover, walk the equipment pad and look for hairline cracks in the pump housing and filter tank, weeping at unions and fittings, and any sign that a valve body has split. Then watch the water level for several days. Losing more than about a quarter inch per day beyond normal evaporation suggests a leak that was not there before.
Also watch for soggy ground near the pool, a heater that will not fire, a cleaner or spa feature with noticeably weaker flow than before, and air bubbles at the returns.
Freeze cracks in underground lines are exactly the kind of leak that requires professional equipment to locate — our post on what a pool leak can do to your property in Austin covers why finding it quickly matters, and our pool repair services handle the plumbing and equipment work once the source is identified.
Get Ahead of Next Winter
The best time to prepare is not the day the forecast turns. Have the equipment pad assessed before winter, confirm freeze protection automation actually works, insulate exposed plumbing, and know where your drain plugs are before you need them in the dark.
It is also worth writing down your own freeze plan and putting it somewhere findable — which breaker controls the pump, which valves to open, where the drain plugs are, and what order to do it in. Hard freezes here tend to arrive overnight and often alongside a power outage, and nobody makes good decisions about pool plumbing at two in the morning by flashlight.
If you travel over the holidays, arrange for someone to check the equipment during a cold snap. A pool that loses power while the owner is out of town for a week is the worst version of this scenario, and it is a common one.
McTarga Pools provides leak detection, plumbing repair, and equipment service across Austin and the surrounding area. Call (512) 998-1188 to schedule an assessment, or to get on the list quickly if a freeze has already caused damage.