How long does an evaporative cooler last?
Updated August 2026
An evaporative cooler, the swamp cooler that cools much of the dry Southwest, lasts 10–15 years. The steel or plastic cabinet and the blower motor set that ceiling, but the parts inside run on far shorter clocks: the cooling pads get replaced every season, the recirculating pump lasts 3–5 years, and the float valve is a $10 part you may swap a few times along the way. In hard-water regions the number drifts to the low end, because mineral scale cakes onto the pads, the pump, and the water pan faster than anywhere else.
Lifespan by type and situation
| Type or situation | Typical lifespan | Why |
|---|---|---|
| Aspen (excelsior) pads | One cooling season | The cheap fiber pads; plan on a fresh set each spring, $15–40 apiece |
| Rigid media (CELdek) pads | 3–5 years | Thicker honeycomb pads cost more up front but survive several seasons |
| Recirculating pump | 3–5 years | A $30–70 part; scale and dry running are what burn it out |
| Blower motor | 10–15 years | Often the part that finally ends the unit; sealed bearings just wear out |
| Cabinet, hard water | 10–12 years | Mineral scale rusts the pan and clogs the water distribution lines |
| Cabinet, descaled and winterized | 15+ years | Yearly cleaning and a fall drain-down reach the top of the range |
Signs yours is near the end
- Weak or warm airflow even with a fresh set of pads, a sign the pump or water lines are scaling shut
- Rust spots or pinholes forming in the bottom of the water pan
- A musty or moldy smell coming off the pads when the unit kicks on
- The pump running but little or no water reaching the top of the pads
- Constant dripping or overflow because the float valve no longer seats
- Motor bearings whining or the blower wheel wobbling on startup
How to add years
Two chores decide whether yours reaches 10 years or 15. Fresh pads every spring and a full pan cleaning keep scale from choking the water flow, which is what starves the pads and cooks the pump. Draining and winterizing the cooler each fall, so no standing water freezes and cracks the pan, is the other half. A season-by-season plan lives in the swamp cooler maintenance checklist, and hard-water homes should add a mid-summer descale. When the blower motor finally goes on a unit past 12 years, replacing the whole cooler usually beats rebuilding it.
What it costs to replace: plan on $1,500–3,500 installed. Replacing on your own schedule, before it fails, is almost always cheaper than the emergency version. The home maintenance cost calculator helps you set the money aside before it comes due.
OnOtto tracks your swamp cooler pad changes age and service history, and warns you before end of life instead of after the flood.
Track your home's systems, free for 30 daysFrequently asked questions
How often do swamp cooler pads need to be replaced?
It depends on the pad type. Cheap aspen (excelsior) fiber pads are a one-season part; replace them every spring for $15–40 a set, sooner if they clog with scale. Rigid honeycomb media pads, often sold as CELdek, cost more up front but survive 3–5 years. Hard water shortens both, because minerals cake onto the fibers and block airflow. If the air coming off the cooler feels warm or weak even after a fresh set, check that the pump is actually pushing water to the top of the pads.
Why does my swamp cooler smell musty?
A musty or moldy odor almost always traces to the pads and the water pan. Pads that stay damp between runs grow mold and mildew, and standing water in the pan does the same, especially at the start and end of the season. Swap in fresh pads, drain and scrub the pan, and run the blower without the pump for a few minutes to dry things out before you shut down for the day. If the smell persists, mineral scale in the water lines may be trapping moisture where it cannot dry.
Do I need to drain a swamp cooler for winter?
Yes, and skipping it is a common way to shorten the unit's life. Drain the pan and supply line every fall so no water is left to freeze and crack the pan or the pump housing. Disconnect and drain the water line, pull or cover the pads, and cover the cooler to keep snow and debris out. A cooler winterized each year and cleaned each spring reaches the top of the 10–15 year range; one left full through a hard freeze can need pan or pump repairs by spring.
Is a swamp cooler cheaper to run than an air conditioner?
Much cheaper on electricity, roughly a quarter of what a central AC draws, because it uses only a fan and a small water pump instead of a compressor. The catch is that it only cools well in dry climates: as humidity climbs, the evaporation that does the cooling stops working, which is why swamp coolers dominate the arid Southwest and are rare in humid regions. They also use water, several gallons an hour on a hot day, so the savings land mostly on the power bill.