Heat Pump Not Cooling in Pleasanton, CA

Heat Pump Not Cooling in Pleasanton

A heat pump cools using the same refrigeration cycle as an air conditioner, with a reversing valve added so the same equipment heats in winter and cools in summer. When a Pleasanton heat pump runs but stops cooling, we diagnose it like a failed AC and then check the reversing valve, the part a cooling-only system does not carry.

Pleasanton is inland Tri-Valley, and the heat is real and dry through the back half of summer. That load is hard on equipment, and the failures cluster accordingly. Pleasanton's housing splits two ways: the older Vintage Hills, Foothill, and downtown corridors run systems from the 1960s through 80s that are in the replacement window, while Ruby Hill and the East Pleasanton estates run newer multi-zone setups. The most common heat-season failure we see across both is capacitor degradation on systems past about eight years, and we carry replacements on every truck.

A heat pump that still runs but will not cool almost always has one failed part, not a dead system. In dry Pleasanton heat that part is frequently a capacitor or a contactor, both inexpensive and quick. We diagnose the actual failure, then put the fix and the price on a written estimate before any work starts.

Common causes

Failed run capacitor. This is the most common heat-season failure we see in Pleasanton. A degraded capacitor leaves the compressor or condenser fan straining or unable to start, so the system runs without cooling, and capacitors degrade faster under repeated heat load. They are inexpensive and we carry them on every truck. We test the capacitor with a meter rather than judging it by appearance, and many of these calls finish in one visit.

Burned or pitted contactor. The contactor is the relay that powers the outdoor unit, and its contacts pit and burn from the frequent cycling that hot Pleasanton summers demand. A failed contactor means the outdoor unit will not energize, so the indoor side runs without cooling. It is a fast, inexpensive replacement, and we inspect and test it alongside the capacitor on every no-cooling call.

Reversing valve stuck in heat mode. This is the failure a straight AC cannot have. The valve that switches the unit between heating and cooling can stick or lose its solenoid coil, leaving the system in heat on the hottest day of the week. We confirm it by reading line temperatures through a mode change. A failed coil is a smaller fix; a stuck valve body is larger, and we show you which it is.

Low refrigerant from a leak. Low charge makes the system run constantly and cool weakly in the heat. On older downtown and tract systems we sometimes find R-22 still in play. It is no longer produced and reclaimed stock is expensive, and a system that leaked once tends to leak again, so we run the repair-versus-replace numbers honestly. On newer systems we find and repair the leak and weigh in a correct charge rather than topping off.

Dirty outdoor coil. A condenser coil packed with dust cannot reject heat in dry summer weather, so the house never cools even with the unit running. It is the cheapest item on the list. We clear the airflow path, wash the coil properly, and recheck operating pressures to confirm the system recovers before going deeper.

Zoning or control-board fault on estate systems. On the Ruby Hill and East Pleasanton multi-zone setups, a stuck damper or a failed zone board can leave part of the house with no cooling while the equipment runs fine elsewhere. This reads like a system failure but is isolated to a zone. We test the dampers and the controller to separate a zoning fault from an equipment fault.

How we diagnose it

Test the run capacitor and contactor at the outdoor unit with a meter first, since these are the dominant heat-season failures in Pleasanton.
Confirm the thermostat is set for cooling and sending the correct reversing-valve signal before chasing equipment.
Read line temperatures and pressures across a mode change to verify the reversing valve is shifting into cooling.
Inspect the outdoor coil for debris and the indoor coil and filter for ice from low airflow.
Pressure-test the charge, identify whether the system is R-22 or current refrigerant, and on estate multi-zone systems test the dampers and zone controller.

$75 diagnostic, credited toward any repair over $200. You get a written quote before any work begins.

Heat Pump Not Cooling in Pleasanton: common questions

How fast can you get to Pleasanton on a hot day, downtown or out at Ruby Hill?

We are based in San Ramon, right next door, and cover all of Pleasanton from the downtown corridors to Ruby Hill and Castlewood. Same-day is best effort, not a guarantee, but a no-cooling call in a hot stretch gets priority. We carry capacitors and contactors on every truck, so many of these finish in one visit.

My system uses R-22. Is it worth fixing the cooling, or should I replace it?

Once R-22 is in play we are honest with you: it is no longer produced, reclaimed stock is costly, and a system that leaked once will tend to leak again. If the repair is small and the system is otherwise sound, we will fix it. If you are facing a recurring leak on old refrigerant, we will run the replacement numbers so you can compare, both on a written estimate.

It is hot out and the unit runs but blows warm. What is the likely cause?

In Pleasanton heat, a unit that runs but blows warm is most often a failed capacitor or contactor that keeps the outdoor unit from doing its job, or a low charge. We meter the capacitor and contactor and pressure-test the charge to pin it down. The diagnostic is $75, credited toward the repair if it comes to more than $200.

Nearby and related

Heat Pump Not Cooling near Pleasanton: Dublin · Livermore · San Ramon .

This is usually a heat pump installation & service in Pleasanton job. See our heat pump installation & service overview or the Pleasanton service area.