AC Not Cooling in San Leandro
San Leandro sits in a mild East Bay band where summer highs run mid-70s to mid-80s near the bay and warmer as you move inland. The AC gets real use on the warm stretches, and a lot of the housing is mid-century suburban stock now on its second or third system. The equipment may be newer than the house, but a unit that runs and will not cool is still usually one failed part, not a system at the end of the road.
Ductwork is the local wrinkle. Many of these homes still have their original ducts, and leaky, undersized ducts starve the indoor coil of airflow. That shows up as weak cooling or a coil that freezes, and it gets misread as a refrigerant problem. We measure airflow and read refrigerant pressures both, so we do not put new refrigerant into a system whose real issue is air it cannot move.
Age is the other thing we watch. Some systems here still run R-22, and when one of those leaks down and blows warm, the honest answer is often replacement rather than another expensive recharge. We put that math in front of you instead of selling you refrigerant twice.
Common causes
Failed run capacitor. The single most common warm-air call. The compressor or fan hums but will not start. We test the capacitor against its rated value and replace it the same visit. It is inexpensive and it strands plenty of otherwise healthy older systems.
Frozen coil from failing original ductwork. Leaky or undersized mid-century ducts starve the indoor coil, it ices over, and cooling stops. We thaw the coil and measure airflow. If duct leakage is high, sealing or replacing duct sections is the real fix, and it makes the AC work as designed.
R-22 refrigerant leak on an aging system. Some San Leandro systems still run R-22. A leak leaves the house warm and the recharge is expensive. We confirm with pressure readings, find the leak, and run the replacement numbers, because reclaimed R-22 is uneconomical and the leak will come back.
Dirty condenser coil. A coil packed with dust and yard debris cannot reject heat, so the unit runs nonstop without cooling. We wash it and recheck the temperature split. On the warm inland afternoons this is often the difference between cooling and not.
Pitted contactor. The relay that starts the compressor wears and pits with age, so the compressor never reliably engages. We inspect for pitting and chatter and replace it if worn. A cheap part that quietly takes the whole system offline.
How we diagnose it
- Read refrigerant pressures and the temperature split to separate a charge problem from an airflow problem before adding any refrigerant.
- Measure airflow and inspect the original ductwork for leakage, a frequent hidden cause of weak cooling in older San Leandro homes.
- Meter the run capacitor and inspect the contactor, the two most common and cheapest failures.
- Check the indoor coil for ice and the filter and blower as the airflow root cause.
- Identify whether the system runs R-22 and, if it is leaking, lay out repair versus replacement numbers on the estimate.
$75 diagnostic, credited toward any repair over $200. You get a written quote before any work begins.
AC Not Cooling in San Leandro: common questions
Are you local enough to San Leandro to come out same day?
My older San Leandro system uses R-22 and is low again. Recharge or replace?
The AC runs but only some rooms cool. Why?
Nearby and related
AC Not Cooling near San Leandro: Oakland · Hayward · Castro Valley .
This is usually a ac repair in San Leandro job. See our ac repair overview or the San Leandro service area.
AC Not Cooling in San Leandro
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