Spring Swamp Cooler Startup Checklist for New Mexico Homes

Pick a calm, dry morning, and allow an hour or two for a cooler in decent shape. Roofs here get slick with dust, and a side panel catches wind like a sail.

Shut off the cooler's power at the breaker and the disconnect before you open anything. Turn off the water supply too, if it has been left on. Use a ladder that extends above the roof edge, and have someone on the ground if you can. OSHA's construction rule is a good yardstick: side rails at least 3 feet above the landing, with the base set out about a quarter of the ladder's working length.

Timing depends on your elevation. A Rio Grande valley home may be ready weeks before one in Edgewood, which sits around 6,600 feet and tends to hold onto cold nights longer. Go by your own forecast rather than a date on the calendar.

National Weather Service Albuquerque averages for 1991 to 2020 show how wide that gap is. The last spring freeze lands around April 6 at the Sunport, April 21 in the Foothills, May 9 at Sandia Park and May 14 at Moriarty, and records run weeks later. Edgewood is not on that table, so use its higher neighbors as a guide.

You also do not need the cooler the first warm afternoon. University of Arizona Extension advises waiting until the outdoor temperature reaches 85 degrees rather than starting at 79, and says that habit can use 50 percent less water.

These rules come up on nearly every cooler conversation.

• Change pads every season unless they still look clean and soft. They are the cheapest performance you can buy.
• Never run the blower with a dry pump for long. You are just pulling hot, dusty air into the house.
• Open a relief window. A swamp cooler needs somewhere to push air. Crack windows on the side of the house you want cooled, or use up-ducts if you have them.
• Look at the ceiling after the first run. Slow leaks show up as a faint stain before they show up anywhere else.
• Book the fall shutdown now, in your head. A line left charged into winter is how a spring startup turns into a plumbing repair.

If the cooler has become more work than it is worth, it may be time to price a swamp cooler to refrigerated air conversion alongside the repair.

Finish by writing down the pad size, belt number and pump model on a strip of tape inside a panel. Next spring's parts run gets much easier. A careful startup, a midsummer pad check and a clean fall shutdown cover most of what a swamp cooler needs, and DOE's own advice comes down to the same thing: clean it and drain it regularly so it keeps running efficiently.