Shut an evaporative cooler down once overnight lows start dropping into the 40s — in Lubbock that usually means late September into October, well ahead of the first hard freeze. Winterizing means killing the power, closing and draining the water line so nothing freezes and splits, emptying and cleaning the reservoir, pulling the crusted pads, and sealing the vent so the cooler stops acting as a hole in your ceiling all winter. The draining step is the one that saves you money; the sealing step is the one you feel on your heating bill.
Plenty of Lubbock homes still cool with an evaporative unit, and for a dry West Texas summer it is a sensible piece of equipment. It is also the only cooling system in town that can cause water damage in January if you walk away from it in October.
When should I shut my swamp cooler down for the year?
When nighttime lows settle into the 40s and the unit stops delivering much relief in the afternoon. In Lubbock that is typically late September through October. Our average first freeze lands around the start of November, but averages are not a schedule — a cold front can drop us below freezing well before that, and the point is to be finished before it does.
Evaporative coolers also lose ground as the air changes. They cool by evaporating water into dry air, so the drier it is outside, the better they work. On a humid morning after a storm, the unit adds moisture without dropping the temperature much — a signal the season is over, not that something is broken.
What does winterizing a swamp cooler actually involve?
Six steps, in this order:
- Cut the power. Turn the cooler off at the switch, then off at the breaker or the disconnect box so the pump and blower cannot start while you are working on it.
- Close the water supply valve. This is usually a small shutoff on the line feeding the cooler, often near the water heater, in a crawlspace, or at a wall penetration.
- Drain and bleed the supply line. Disconnect it at the cooler's float valve and let it empty completely. A charged line is what bursts.
- Empty and clean the reservoir. Pull the drain plug, then scrape and rinse out the sediment sitting in the bottom of the pan. Let it dry fully before you close things up.
- Remove the pads. Take out the old media so it is not sitting damp and crusted in a steel cabinet for five months.
- Cover and seal. Fit a cover over the unit outside, and close or block the duct opening inside.
Two honest cautions. If your cooler sits on the roof, that is a ladder-and-roof job on a windy plateau, and a fall costs more than a service call — hire it out if you have any doubt. And if the disconnect box, the wiring, or the pump circuit looks corroded or unfamiliar, leave electrical work to a licensed pro.
Rooftop cooler, and not thrilled about the ladder?Call and we'll connect you with a local Lubbock pro who can shut it down for the season.
📞 (414) 429-5333Why is hard Lubbock water so hard on an evaporative cooler?
Because the machine works by evaporating water and leaving everything the water carried behind. South Plains water is hard, so a season's worth of minerals ends up crusted on the pads, caked in the bottom of the pan, and narrowing the distribution tubes that are supposed to wet the media evenly. Scale also builds on the float valve, which is why a cooler that ran fine in June sometimes overflows or runs dry by August.
That is what makes the fall cleanout worth doing properly rather than just flipping the switch. Sediment left in the pan holds moisture against bare metal and accelerates rust, and pads left in place go stiff and block airflow. If your unit has a bleed-off line that dumps a little water continuously to keep mineral concentration down, check that it was actually flowing this season — a plugged bleed-off is a common reason for heavy scale.
How do I stop cold air pouring in through the cooler all winter?
Treat the vent as a hole in your building envelope, because that is exactly what it is. An uncovered cooler gives cold air, dust, and the occasional bird a direct path into the house, and a house that is losing heat through a ceiling vent will run its furnace harder all season.
Close the damper if the ductwork has one, and add an insulated vent cover on the inside of the register. Outside, a fitted cover over the cabinet keeps blowing dust and moisture out of the housing. Do the outside cover only after the unit is drained and dry — sealing a wet cabinet traps moisture and rust.
This is a natural weekend to pair with the rest of your seasonal changeover. The furnace has been sitting idle through a dusty summer, and our fall furnace prep checklist covers the filter, thermostat, vent, and carbon-monoxide checks worth doing before the first cold night. If the furnace does not fire cleanly when you test it, that is the moment for heating service, not the moment the temperature hits 25 degrees.
Is this the year to switch to refrigerated air?
Worth asking if you are already paying for annual pad changes, scale cleanouts, and a shutdown-and-startup ritual twice a year. Evaporative cooling struggles on humid days and cannot dehumidify, which is why many Lubbock homeowners eventually convert. The tradeoff is real: a conversion means new equipment, and often duct and electrical work with it, so it is a planned project rather than a weekend fix.
Autumn is the right time to gather quotes, while nobody is working through a heat-wave backlog. Costs vary widely with the size of the house, the state of the existing ductwork, and the equipment chosen — get a written quote rather than a number over the phone. When you are ready to price a system, we can connect you with a local pro for a replacement quote. Prefer not to call? Request a callback and we will get you connected with an established local company.
Frequently asked questions
Can I leave my swamp cooler running into the fall?
You can run it on warm afternoons, but it stops earning its keep once nights cool off, and leaving it charged with water into freezing weather is what splits supply lines. A reasonable rule for Lubbock is to stop using it when overnight lows settle into the 40s, then winterize on the next dry, calm weekend rather than waiting for a freeze warning.
Do I really need to drain the water line before winter?
Yes. The small supply line feeding the cooler is the single most likely thing to freeze and burst, because it is thin, often uninsulated, and usually runs outdoors or through an unconditioned space. Water expands as it freezes, and a split line does not announce itself until spring when the valve is turned back on and water runs into a wall, an attic, or down a roof.
How much does it cost to winterize an evaporative cooler in Lubbock?
It varies with the type of cooler, where it sits, and whether pads and a cover are replaced at the same time. A ground-level or side-wall unit that a homeowner can safely reach costs far less to have serviced than a rooftop unit that requires ladder and roof work. Call for a quote rather than working from a number you found online.
Should I replace the pads now or wait until spring?
Either works, as long as the old pads come out before winter. Leaving crusted, damp pads sitting in the unit all winter encourages rust, odor, and mineral buildup. Many homeowners pull and discard the old pads in the fall and install fresh ones in the spring, so the cooler starts the season with clean media and full airflow.
Does Hub City winterize swamp coolers?
No. Hub City is a referral service, not a contractor. We connect Lubbock homeowners with independent local HVAC pros who service evaporative coolers and, when the time comes, quote refrigerated-air conversions. Pricing, scheduling, and any warranties come from that pro. Call (414) 429-5333 and we will get you connected.