Heat Pump Not Heating in San Jose, CA

Heat Pump Not Heating in San Jose

San Jose sells equipment on the cooling side. Summers run hot, often in the high 80s and 90s. But every heat pump we install also carries the heating load all winter, and local winters are mild enough that the equipment is rarely stressed. When a San Jose heat pump stops heating, the cause is almost always a single failed component, not an undersized system giving up.

We see this across the city's whole housing spread. On the newer ducted heat pumps in North San Jose and post-2000 stock, the usual suspects are a stuck reversing valve, a defrost control fault, or low refrigerant. On ductless mini-split retrofits, common in the city's Eichler neighborhoods, a no-heat call usually points at one outdoor head's reversing valve or a communication fault between the indoor head and the condenser, since those systems are inverter-driven and self-report differently than a conventional split.

The reflex is to assume the heat pump cannot handle a cold snap. In San Jose it can. We find the actual fault and put it on the written estimate before any repair. The $75 diagnostic is credited toward the repair when it runs over $200.

Common causes

Reversing valve stuck. The valve that switches the system into heating can hang or its solenoid can fail, leaving the unit running but blowing cool air. We read temperatures across the valve and listen for the solenoid on a mode change. A bad coil is cheap; a seized valve body is a valve replacement.

Inverter mini-split fault code (Eichler retrofits). On ductless systems in Eichlers, a no-heat condition often shows as a fault code for a communication error, a sensor out of range, or a defrost lockout. We pull the code at the indoor head, confirm it against the line set and wiring, and clear the actual fault instead of swapping parts blind.

Defrost control fault. San Jose mornings get cold and damp enough to ice the outdoor coil, and a working defrost cycle has to clear it. A failed defrost board or sensor leaves the coil iced and the unit unable to absorb heat. We check defrost timing and sensor resistance and confirm the unit reverses to melt the ice.

Low refrigerant charge. A leak drops heating capacity until the system cannot keep up. We measure superheat and subcooling, locate the leak, and repair it rather than topping off. On older R-410A equipment we give you the straight repair-versus-replace numbers.

Contactor or capacitor failure. A pitted contactor or weak run capacitor keeps the outdoor unit from starting, so there is no heat at all. Both are quick meter checks and we stock them. This is one of the most common and cheapest no-heat fixes we run.

How we diagnose it

Confirm heat mode and a valid heat call from the thermostat or controller.
On ducted units, read line temperatures across the reversing valve; on mini-splits, pull and verify the fault code.
Inspect the outdoor coil for ice and test the defrost board and sensor.
Measure refrigerant charge and trace any leak before recharging.
Meter the contactor and capacitor at the condenser.

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

Heat Pump Not Heating in San Jose: common questions

You are based in San Ramon. Do you really service San Jose?

Yes. San Jose is a regular part of our South Bay route. We dispatch the nearest tech and aim for same-day on no-heat calls when the schedule allows, which is best effort rather than a hard promise. You will get a real arrival window when you call.

We barely use heat in San Jose. Is it worth fixing the heat pump now?

Usually yes. Most San Jose no-heat faults are inexpensive parts like a capacitor, a contactor, or a defrost sensor, and ignoring them risks the compressor on the next start. If the diagnosis turns up a major refrigerant or compressor problem on aging equipment, we will tell you honestly whether repair or replacement is the better money.

My ductless Eichler system shows an error code and no heat. What is that?

On inverter mini-splits, a no-heat code is most often a sensor reading out of range, a defrost lockout, or a communication fault between the head and the condenser. We read the specific code at the unit and fix the named fault rather than guessing, since these systems do not behave like conventional splits.

Nearby and related

Heat Pump Not Heating near San Jose: Santa Clara · Milpitas · Cupertino .

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