Water or Ice Around Unit in Spokane, WA

There are several distinct failure points that lead to water or ice. They don't all look the same, and they don't all get fixed the same way.

Restricted Airflow Across the Evaporator Coil

This is the most common cause of a frozen coil, and it's often the simplest to fix. The evaporator coil works by absorbing heat from the air moving across it. When airflow drops due to a clogged filter, a dirty coil, or a failing blower motor the coil surface gets too cold. Moisture in the air freezes on contact instead of draining away as condensate.

The coil is essentially doing its job too well in one spot because it's not getting enough warm air to balance it out.

Spokane's housing stock includes a large number of homes built during the construction booms of the late 1990s and 2000s. Many of those builder-grade AC systems are now 15–20 years old. The blower wheels on those units accumulate years of dust and debris, reducing airflow gradually so gradually that homeowners don't notice until there's ice on the coil.

Low Refrigerant (Refrigerant Leak)

Refrigerant doesn't get "used up" like fuel. If your system is low on refrigerant, there's a leak somewhere in the sealed circuit. Low refrigerant causes the pressure in the evaporator coil to drop below normal. When pressure drops, so does the coil temperature well below the freezing point of the moisture in your air.

The result: ice forms on the coil and sometimes travels up the refrigerant lines toward the outdoor unit.

A refrigerant recharge without finding and fixing the leak is a temporary fix. The refrigerant will leak out again. The root cause is the leak itself.

Condensate Drain Blockage

Your AC system removes humidity from the air as it cools. That moisture drips off the evaporator coil into a drain pan, then exits through a condensate drain line. In Spokane's warm, humid summer months, that drain line can accumulate algae, dust, and debris over time.

When the drain line clogs, the pan fills up and overflows. That's the puddle on your floor. It's not ice it's a plumbing problem inside your HVAC system.

Homes in neighborhoods like Browne's Addition and South Perry often have older air handlers in tighter mechanical spaces where drain lines weren't always installed with ideal slope. A low-slope drain line is more prone to standing water and biological growth.

Dirty Evaporator Coil

Even with a clean filter, the evaporator coil itself can accumulate a thin layer of dust and debris over years of operation. That layer acts as insulation, reducing heat transfer. The coil surface temperature drops, and ice forms.

A dirty coil also restricts airflow on its own, compounding the problem. It's a slow failure one that builds over multiple seasons until the system stops working on a hot July afternoon.

Frozen Coil From Short Cycling

If your system is turning on and off too frequently a condition called short cycling the coil may not have enough run time to properly manage the refrigerant cycle. This can also lead to coil icing under certain conditions.