Fast, Reliable Emergency & Commercial HVAC Across San Lorenzo
When your floor furnace dies on a December night or your commercial kitchen exhaust fails before the lunch rush, waiting days for a callback isn’t an option. In San Lorenzo, we answer emergency HVAC calls with same-day response and show up ready to work. Daniel Okafor personally handles the repair, whether it’s a 1948 Bohannon ranch on Via Del Rancho or a retail space on Hesperian Boulevard. Call (855) 600-3322 now for emergency service or a free estimate on commercial work.
Why Northstar Heating & Air San Francisco Is San Lorenzo’s Preferred Emergency & Commercial HVAC Company
San Lorenzo customers have left us 357 verified reviews averaging 4.9 stars, and a surprising number mention the same thing: Daniel is the one who actually shows up. Not a subcontractor. Not a rotating technician who needs directions to Hesperian. The owner himself.
That matters more here than in most East Bay cities. San Lorenzo’s housing stock is unusually uniform, almost entirely David Bohannon post-WWII tract homes built between 1944 and 1952. When Daniel walks into your living room and spots the original floor-furnace cutout in the subfloor, he already knows the crawl space clearance, the pier-and-post foundation layout, and which replacement parts will actually fit. Ten years of serving this exact ZIP code builds that kind of pattern recognition.
Our response time to San Lorenzo averages under 90 minutes for true emergencies: no heat in winter, no cooling during heat events, or any commercial system failure that threatens inventory or safety. We’re familiar with the traffic patterns on I-880 and surface routes through Ashland and San Leandro, so we route efficiently rather than guessing.
Commercial customers on Washington Avenue and the industrial pockets near the BART corridor get the same direct access. Daniel handles commercial HVAC himself rather than delegating to a separate commercial division, so your rooftop unit or chiller service doesn’t get lost in a corporate queue.
Our Emergency & Commercial HVAC Services in San Lorenzo
24/7 Emergency HVAC
Emergency calls in San Lorenzo follow a distinct seasonal pattern. Winter no-heat emergencies often involve original mid-century floor furnaces that finally failed after 70+ years of service. Most suppliers stopped stocking those parts decades ago, so sourcing replacements requires relationships with specialty distributors and creative retrofit knowledge. Summer emergencies spike during prolonged heat events when poorly insulated 1940s ranch homes overheat and window units or newly installed mini-splits strain against impossible thermal loads. Our Emergency & Commercial HVAC team carries the tools and common parts to handle both scenarios without a return trip.

Commercial HVAC
San Lorenzo’s commercial base spans restaurants along Hesperian, light industrial near the BART corridor, and retail in the Washington Avenue corridor. Each building type presents different challenges: restaurant grease loading on rooftop units, aging packaged systems in 1960s strip malls, or tenant improvement HVAC for spaces that have been reconfigured multiple times. Daniel personally assesses commercial jobs, sizes equipment correctly for actual load rather than rule-of-thumb guesses, and coordinates with your facilities team or property manager directly.

Rooftop Unit (RTU) Service
Flat-roof commercial buildings in San Lorenzo’s older retail and industrial areas typically rely on packaged rooftop units. These systems take a beating from East Bay sun exposure and the particulate load from nearby I-880 traffic. We service RTUs from Goodman, Rheem, and York with fast turnaround because we stock common control boards, blower motors, and refrigerant components locally. For full replacements, we coordinate crane access and minimize business disruption.

Chiller Service
While chillers are less common in San Lorenzo’s smaller commercial footprint, the medical offices, data-adjacent operations, and specialty manufacturing spaces that do rely on them can’t tolerate downtime. Daniel’s 10 years of field experience includes chiller diagnostics, refrigerant management, and controls troubleshooting. We don’t refer chiller work out to a separate contractor; we handle it directly, with the same accountability that applies to every job we touch.

What happens when you call
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A real person answersNo phone trees — you reach a local pro.
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You get an upfront price rangeHonest numbers before anyone is dispatched.
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A background-checked tech heads outLicensed & insured, dispatched right away.
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You approve before work beginsNothing starts until you say go.
Trusted Brands We Service in San Lorenzo
We maintain active certification and hands-on experience with 9 major HVAC brands: Carrier, Trane, Lennox, Goodman, Rheem, York, Daikin, Bryant, and American Standard. For San Lorenzo customers, this means no brand mismatches, no “we’ll have to call someone else,” no referral runarounds. We stock common Goodman and Rheem parts locally for faster turnaround on emergency calls, and our familiarity with Daikin systems is particularly relevant for the ductless mini-split retrofits that dominate new cooling installs in Bohannon-era homes. Nine major brands, one company, one technician who owns the outcome.
Common Emergency & Commercial HVAC Problems We See in San Lorenzo Homes
- Original floor furnace failure in December. A large number of Bohannon homes still have their original mid-century floor furnaces recessed into the living room subfloor. When one fails, the homeowner has zero backup heat source. Emergency no-heat calls in San Lorenzo disproportionately involve sourcing parts or replacements for models that most suppliers stopped stocking decades ago.
- First-time AC install in homes that never had cooling. San Lorenzo sits in the East Bay flatlands, historically kept moderate by the afternoon Delta breeze and marine layer. But growing heat event frequency now pushes indoor temps in poorly insulated 1940s homes past comfort, driving AC installs in houses that went 70+ years without any cooling equipment.
- Ductless mini-split sizing errors from previous contractors. The defining HVAC challenge in San Lorenzo is the no-duct retrofit into a 1,000–1,200 sq ft ranch home never engineered for forced air. Contractors unfamiliar with Bohannon construction often oversize or poorly locate outdoor units, creating noise complaints and efficiency losses.
- Commercial exhaust and makeup air imbalance. Restaurants on Hesperian Boulevard and in the Washington Avenue corridor frequently struggle with kitchen hood exhaust that overwhelms the building’s original HVAC balance, creating negative pressure, door suction, and temperature stratification that standard thermostat adjustments can’t fix.
Pricing for Emergency & Commercial HVAC in San Lorenzo, CA
We believe in upfront numbers, not surprises after the work is done. A typical emergency HVAC repair in San Lorenzo runs $175–$765 for AC work and $175–$825 for furnace or floor-furnace repair, depending on whether we’re replacing a control board, blower motor, or addressing a refrigerant leak. Commercial service calls start in the same range but can extend higher for rooftop unit compressor replacement or chiller refrigerant recovery.
Annual maintenance and tune-ups in San Lorenzo cost $95–$235, a worthwhile investment given the age of most residential systems here. New AC installation, increasingly common for first-time cooling in Bohannon homes, typically runs $4,130–$8,850 depending on whether we configure a ductless mini-split system or find a path for limited ductwork.
Emergency after-hours rates apply for nights and weekends, but we quote the total before starting work. Call (855) 600-3322 for an exact quote on your specific situation. Estimates are free.
We Also Serve Cities Near San Lorenzo
Our service radius extends naturally from San Lorenzo into neighboring communities. We regularly handle calls in Ashland and Cherryland along the I-880 corridor, San Leandro to the north, and Castro Valley to the east. If you’re in one of these areas and need immediate help, we also offer AC Repair & Installation in San Lorenzo and Heating & Furnace in San Lorenzo with the same owner-direct service model.
Serving San Lorenzo, CA — Our Local Coverage Area
We’re based in the San Lorenzo area and know this community well. Use the map below to see our service coverage — if you’re nearby, we can almost certainly help.
FAQs — Emergency & Commercial HVAC in San Lorenzo
We typically arrive within 90 minutes for true emergencies in San Lorenzo, including the Via Del Rancho and Hesperian Boulevard corridors. Our familiarity with I-880 patterns and surface routes through Ashland and Cherryland helps us route efficiently. Call (855) 600-3322 for immediate dispatch.
Yes, we service the entire 94580 ZIP code, with particular expertise in the original Bohannon post-WWII subdivisions where floor furnaces and no-duct construction create unique HVAC challenges. Daniel has personally worked in dozens of these homes and knows their construction patterns.
Yes, we offer emergency HVAC availability for urgent residential and commercial needs, including nights and weekends. After-hours rates apply, but we provide the full quote before starting any work. Call (855) 600-3322 for emergency dispatch.
Base labor rates are consistent across our service area, but San Lorenzo’s older housing stock can affect total job cost. Retrofitting cooling into a 1940s Bohannon ranch without existing ductwork typically requires ductless mini-split expertise rather than conventional forced-air installation, which changes equipment selection and labor scope. We quote each job individually after inspection.
We stand behind our work with warranty coverage on parts and labor for all San Lorenzo repairs and installations. Specific terms vary by equipment type and manufacturer, but our 4.9-star average across 357 reviews reflects how we handle the rare warranty call: Daniel personally follows up and resolves it. Call (855) 600-3322 to discuss warranty details for your specific project.
Written by Daniel Okafor, Owner and Lead Technician at Northstar Heating & Air, serving San Lorenzo and the East Bay since 2014.