Swamp cooler or refrigerated air in Tucson
A swamp cooler is cheaper to buy and run and works well in Tucson's dry heat before the monsoon. Refrigerated air keeps working through the humid months. If you want to be comfortable in July and August, I'd choose refrigerated air.
On this page
The short comparison
| Evaporative (swamp) cooler | Refrigerated air | |
|---|---|---|
| Installed cost | $1,500 to $3,500 (Fixr) | $5,800 to $14,400 for central AC (Fixr) |
| Energy use | About one quarter of central AC (DOE) | Higher |
| Works best | Hot, dry air (DOE) | Any weather |
| Uses water | Yes | No |
| Windows | A window or vent must be open (DOE) | Closed |
| Upkeep | Regular cleaning of the water reservoir, pads (DOE) | Yearly tune-up, filters |
The energy and upkeep notes are from the Department of Energy's homeowner HVAC guide (2011) and Energy Saver guide (2022). Costs are Fixr's national figures.
What the monsoon does
The DOE says evaporative coolers work well where the air is hot and humidity is low. Tucson in May and June fits. The monsoon months, July through September, bring 52% of the airport's yearly rain (1991-2020 average, about 5.5 inches of 10.59), and the humidity rises with it. Those are also the months with the warmest nights: July lows now average 77.6°F. A cooler can't do much with humid air, and that is when people in swamp-cooled houses are least comfortable.
Average daily high and low by month, Tucson International Airport
What conversion involves
- A central air conditioner or heat pump, sized with a load calculation.
- Ductwork. A cooler duct is usually not laid out for refrigerated air, so many homes need new or resized supply and return ducts.
- Closing and sealing the roof opening where the cooler sat.
- Electrical work for the outdoor unit if the panel needs it.
In older parts of town conversion comes up a lot. 39% of homes in the ZIP codes we cover were built before 1980 (Census ACS 2020-2024). ZIP by ZIP.
When I would keep the cooler
If your budget doesn't stretch to conversion, a well-maintained cooler plus a ductless mini split for the bedroom gets you through the monsoon nights. Mini splits. If you already have both, run the cooler in the dry months and close it off when you switch to refrigerated air.
Questions Tucson homeowners ask
Is a swamp cooler cheaper to run than AC?
Yes. The Department of Energy says evaporative coolers can use about one quarter as much energy as central air conditioners. They also use water, which should be counted in the cost.
Do swamp coolers work during the monsoon?
Not well. The DOE says they work best in hot, dry air. When monsoon humidity rises in July and August, a cooler can't lower the temperature as much.
Sources
- US DOE / PNNL: Energy Renovations, HVAC: A Guide for Contractors to Share with Homeowners (August 2011)
- US DOE: Energy Saver Guide (2022)
- Fixr: Swamp Cooler Installation Cost (updated August 29, 2025)
- Fixr: Cost to Install Central Air (updated August 29, 2025)
- NOAA NCEI daily summaries, Tucson International Airport (USW00023160)