Step 1: Is there water in the pan?
The pump can only move water if it's sitting in it. If the pan is dry, the problem is upstream — the water supply valve, the float valve, or the fill line — not the pump itself. Confirm the supply is on and the float lets the pan fill to roughly an inch below the overflow.
Step 2: Check the float and water level
A float set too low starves the pump; a float stuck closed keeps the pan empty. Gently lift the float — you should hear water begin to fill. If the pan overfills instead, the float needs adjusting or replacing.
Step 3: Clear the suction screen and impeller
Albuquerque's hard water and dust clog the small screen at the base of the pump and can jam the impeller with scale. With power off, many pumps let you pop off the base and clear the debris. A pump that hums but moves no water often has a scaled or stuck impeller.
Step 4: Suspect the pump motor or capacitor
If the pan is full, the screen is clear, and the pump still won't run — or hums and cuts out — the pump motor has likely failed. Evaporative-cooler pumps are sealed and inexpensive, so replacement is usually the practical fix. A humming pump that repeatedly trips can point to an electrical fault.
When a new pump is the answer
Because these pumps are cheap and sealed, most technicians replace rather than rebuild them. The key is sizing the replacement to your cabinet so it lifts enough water to every pad. See pump repair & replacement, or call us and we'll bring the right part.