Heat Pump Repair in San Jose, CA
Heat pump stuck in one mode, blowing cold air, or icing over? We repair reversing valve, defrost, and refrigerant problems on every brand.
Heat Pump Repair in San Jose & the Bay Area
A heat pump doing double duty as your furnace and AC has more moving parts that can fail than either system alone — and when it does, you lose heating and cooling at once. Promax repairs heat pumps across San Jose and Santa Clara County from every major manufacturer, diagnosing the failures unique to heat pumps: a stuck reversing valve, a defrost cycle that won't clear, or a refrigerant charge that's drifted out of spec.
The reversing valve is what lets a heat pump switch between heating and cooling, and when it sticks, the system gets stuck in one mode or blows the wrong-temperature air entirely — a classic 'heat pump blowing cold air in winter' complaint that isn't always a refrigerant problem. A failing defrost control, sensor, or board can leave the outdoor coil caked in ice through an entire cold snap instead of clearing normally, which throttles heating output and can damage the compressor if it runs iced up for too long.
Refrigerant issues show up differently in a heat pump than in a straight AC, because the system needs the correct charge in both heating and cooling mode — an undercharge that seems fine in summer can leave you with weak heat all winter. Our techs are trained across Mitsubishi, Bryant, Daikin, Carrier, Trane, and other major heat pump brands, and most repairs — reversing valves, defrost boards, sensors, and refrigerant leaks — are diagnosed and quoted in a single visit.
Heat Pump Repair, Done Right
Every heat pump repair visit is built around three things: finding the real cause, fixing it with parts already on the truck, and getting a licensed technician to your door fast. Same-day service for no-cool, no-heat and no-hot-water calls, 7 days a week. Diagnostic fee waived with any repair.
- Fully stocked trucks carry parts for most repairs on the first visit
- We repair Mitsubishi Electric, Bryant, Daikin and every other major brand
- Licensed, EPA-certified technicians on every call
- We stand behind our work — service and spare parts are both covered
What's Included With Heat Pump Repair
Every heat pump repair visit covers the items below, and the scope and price are confirmed in writing before any work starts. When it's finished the technician walks you through what was done and what to watch for. We call back within one business hour, 7 AM – 10 PM.
- Reversing valve and defrost cycle diagnosis
- Refrigerant leak detection, repair, and correct dual-mode recharge
- Sensor, control board, and capacitor replacement
- Outdoor coil de-icing and airflow restoration
- Upfront flat-rate pricing before any repair begins
- All major brands, whether or not we installed the system
Signs You Need Heat Pump Repair
Each symptom below means a part is wearing out or already failing, and these problems rarely fix themselves. Waiting usually lets a small fault damage other components, which turns a modest repair into a larger one and raises the odds of a breakdown at the worst possible time. Call (669) 777-1997 or book online, and a technician will pinpoint the cause.
- The system blows cold air when set to heat, or warm air when set to cool
- The outdoor unit is caked in ice that doesn't clear during a normal defrost cycle
- Heating output is weak even though the system is running
- The system is stuck in one mode and won't switch
- Short-cycling, or unusual noise from the outdoor unit
- Rising electric bills without a change in how you use the system
Brands We Repair
Promax is a Mitsubishi Diamond Contractor and Bryant Factory Authorized Dealer, so Mitsubishi Electric and Bryant equipment is repaired by technicians with factory-backed training. We repair every other major brand as well, whatever name is on your equipment. Our fully stocked trucks carry common parts for these brands, so most repairs are finished in a single visit.
Need heat pump repair help in San Jose?
Related Services
Most heat pump repair jobs touch one of these, and the same licensed Promax team handles all of them. Each page lists what's included, typical costs and the questions San Jose homeowners ask most. Not sure which you need? Call (669) 777-1997 and we'll point you to the right one.
Where We Work
Promax Service Group serves homes and businesses in San Jose, across Santa Clara County, and in nearby Peninsula and East Bay cities. Same-day service for no-cool, no-heat and no-hot-water calls, 7 days a week. Choose your city for local details, or call (669) 777-1997 to confirm we cover your address.
Frequently Asked Questions
Why is my heat pump blowing cold air when it's set to heat?
The most common cause is a stuck or failing reversing valve, which controls whether the system heats or cools. Other causes include a low refrigerant charge, a defrost cycle that's stuck on, or (in mild weather) the system briefly running in defrost mode, which is normal for a minute or two but not longer. We diagnose which one it is on-site.
Why is the outdoor unit covered in ice?
Some frost during a normal defrost cycle is expected in winter, but a coil caked in solid ice means the defrost control, sensor, or board has failed and the system isn't clearing itself. Running it iced up for an extended period can damage the compressor, so it's worth having it checked rather than waiting for it to clear on its own.
Do you repair heat pumps you didn't install?
Yes — we repair every major heat pump brand regardless of who installed it: Mitsubishi, Bryant, Daikin, Carrier, Trane, and others. Being a Mitsubishi Diamond Contractor gives us deeper factory training on Mitsubishi specifically, but it doesn't limit what brands we work on.
How is heat pump refrigerant charging different from an AC?
A heat pump has to hold the correct refrigerant charge in both heating and cooling mode, using a reversing valve to switch flow direction. A charge that looks fine in summer cooling mode can still be wrong for winter heating, which is why heat pump refrigerant work needs mode-specific testing, not just a single summer check.
What does heat pump repair cost in San Jose?
Common repairs like capacitors, sensors, and defrost boards typically run $200–$600. Reversing valve replacement and refrigerant leak repairs cost more depending on the part and refrigerant type. You'll get a firm quote before any work begins, and the diagnostic fee is waived when you approve the repair.
My heat pump is short-cycling — what causes that?
Short-cycling usually points to a dirty filter restricting airflow, a failing capacitor, an oversized system for the space, or a refrigerant charge issue tripping a safety control. It wastes energy and wears the compressor faster, so it's worth diagnosing early rather than letting it continue.