Load calculation and sizing
Equipment is sized to the house, not to the old furnace label. Oversized systems short cycle and cost more.
Switching a Fremont home from gas heat to a heat pump? HAXX sizes the system, reviews panel capacity and files the city permit before install day.
Serving Mission San Jose, Niles, Irvington, Centerville, Glenmoor and Ardenwood and the rest of Fremont. Share your address to confirm availability.

A heat pump replaces a furnace and AC with one system for heating and cooling. Good results come from sizing, layout and electrical planning done before equipment is ordered.
Equipment is sized to the house, not to the old furnace label. Oversized systems short cycle and cost more.
Keep existing ducts when they are in good shape, or go ductless where ducts are missing, leaky or impossible to run.
HAXX electricians review the panel and service before the install, so a surprise panel upgrade does not appear mid-project.
Mitsubishi Electric and American Standard systems, among others, matched to the home and budget.
HAXX pulls the mechanical and electrical permits and meets the city inspector.
We point you to the rebates your address qualifies for and provide the equipment documentation programs ask for.
Fremont homes get their electricity from Ava Community Energy, with PG&E handling delivery. That affects which rebates apply and how you are billed once the house runs on electric heat.
Ava Community Energy points customers to rebates through its Incentive Finder, and BayREN runs regional programs. Terms change often, so HAXX checks them before you commit.
Fremont hit 110°F in September 2022. HAXX sizes cooling capacity for heat waves, not only for mild winters.
Ranch homes with attic ducts take ducted systems; older Niles and Irvington homes without ducts often suit ductless or slim-ducted units.
Rated 4.8 across 515+ reviews on Housecall Pro, Google and Facebook. Read more reviews.
“Thorough diagnostics of A/C system, identified and repaired the issue quickly!”
“Service was performed well and on time. Service person was highly skilled and provided easy to understand options to deal with the issue. Price for diagnostics was reasonable and easy to pay online.”
“Our commercial building had several HVAC problems, and their team carefully diagnosed each unit, explained the available options, and never pressured us into unnecessary replacements. They worked hard to repair what could be repaired and kept us informed throughout the process.”
Existing equipment, home layout and what you want to improve.
Sizing, airflow, equipment placement and electrical needs.
Options, exclusions, permit requirements and any eligible incentives.
Confirm equipment, scheduling and handover details with HAXX.
A closer look at recent heating and cooling work by HAXX. Projects in Fremont are marked with the city.

On site during a commercial VAV box repair: access above a suspended ceiling, equipment and the work in progress.
Explore recent projects
Heat pump installation.

Outdoor heat pump installation.

Heat pump air handler installation.

Compressor replacement.

Heat pump air handler service.

Lennox ac installation.

Mitsubishi leak detection.

Leaking coil replacement.
Programs come and go through Ava Community Energy, BayREN, PG&E and the state. HAXX reviews what is available for your project at the estimate; confirm current terms with each program.
Yes. HAXX applies for the permit through the City of Fremont and is on site for the inspection.
Yes. Bay Area winters are mild, and correctly sized heat pumps heat comfortably through them. Sizing and duct condition matter more than the brand.
Most single-system replacements take one to three days on site. Permits, equipment lead times and any electrical work add to the overall timeline.
Share the property, equipment and questions you have in mind.
(408) 901-8315
Call HAXX to discuss your property and scheduling.
