Seasonal tune-up and full diagnostic on your Carrier, Trane, or Goodman system - readings shown to you before any repair is proposed
Diagnosis first, numbers second - you approve the repair price before a single part goes in.
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AfterFast, Reliable Furnace Repair Across San Lorenzo
Furnace repair in San Lorenzo typically runs $150 – $700 for diagnostic plus standard parts and labor, with most jobs completed same-day or next-day. Our Furnace Repair team knows this area’s specific failure patterns, and we answer the phone live around the clock at (361) 306-9515. If your furnace locked out overnight or is short-cycling through these damp winter nights, we’ll get a background-checked tech to your door inside the stated window, with a written price before any work begins.
San Lorenzo sits in a low-lying marine pocket of the East Bay, and that matters for furnaces. The air here is mild and humid rather than truly cold, which shapes what breaks and when. More on that below.
Key Takeaways
- Most San Lorenzo furnace repairs run $150 – $700, with the price in writing before we start.
- Overnight lockouts and short-cycling are the dominant winter calls here, driven by corroded flame sensors and control boards from damp crawlspaces.
- Every repair is guaranteed in writing for a full year. If it fails in that window, we return at no charge.
- We service Carrier, Trane, Lennox, Goodman, Rheem, York, Daikin, Bryant, and American Standard.
Why Dalton Heating & Air Is San Lorenzo’s Preferred Furnace Repair Company
Dalton Heating & Air is a Garrison Partners company, operating under The Garrison Standard since 2003. That standard is not a slogan. It is a set of non-negotiable terms: arrive inside the stated window, put the price in writing before starting, do the job by the book, leave the site clean, and stand behind the work for a full year. Every technician who comes to your San Lorenzo home is background-checked and uniformed, and every repair includes a written guarantee.
Marco Benitez leads the team, and he holds every tech to The Garrison Code on every call, whether it’s a no-heat lockout near the San Lorenzo Library or a blower motor replacement off Bockman Road. We answer the phone with a live person 24 hours a day, seven days a week, because a furnace that quits at 2 a.m. in January should not go to voicemail. Dispatch and scheduling for San Lorenzo are coordinated from our San Francisco Bay Area office, with crews serving the area locally. When you call (361) 306-9515, you get a person, not a queue.
Our reputation in San Lorenzo is built on showing up and doing what we said we’d do. The written price, the written guarantee, and the free return visit if a repair fails are standard on every job, not upgrades you have to ask for.
Furnace Maintenance in San Lorenzo
Furnace Maintenance in San Lorenzo matters because of how this area’s climate treats a furnace, and a seasonal safety check runs $80 – $200. San Lorenzo’s damp, marine air settles into crawlspaces and garages, and that moisture attacks flame sensors, control boards, and electrical connections long before hard cold would ever stress the mechanical parts. A furnace that runs perfectly in October can be locking out by December simply because a flame sensor glazed over or a board connector corroded.
What a Tune-Up Covers
Our tune-up includes cleaning or replacing the flame sensor, checking the burner assembly, testing the control board and ignition sequence, measuring blower motor amp draw, and verifying carbon monoxide safety. We also check static pressure and duct condition. You get a written report of what we found and what we did. Our techs are not paid on what they sell, so the report is just that: a report.
When San Lorenzo Homes Need It
Because winters here rarely force hard runtimes, a failing capacitor or dirty sensor can sit unnoticed for months. Then the first genuinely cold snap hits and the furnace won’t fire. A $80 – $200 tune-up in October or November catches most of those failures before they become a same-day no-heat repair. If we do find something during a tune-up that needs repair, the repair price is written and in your hand before we touch a wrench.
Heat Pump Repair in San Lorenzo
Heat Pump Repair in San Lorenzo covers systems that many homeowners here now run year-round, since the mild climate makes a heat pump a sensible choice for both heating and cooling, and when it’s time for a new system, our Heat Pump Installation in San Lorenzo is available. The repair work runs the same $150 – $700 band as furnace repair for diagnostic and standard parts and labor. Heat pumps fail differently than furnaces: reversing valves stick, defrost boards short, and the outdoor coil collects the same marine moisture that corrodes furnace internals.
What We Check on Heat Pumps
On a heat pump call, we check the reversing valve operation, the defrost cycle, refrigerant charge, and the outdoor unit’s electrical connections. We also verify the heat pump is switching modes correctly between heating and cooling, since a stuck valve in January means cold air blowing from the registers. The fix is usually straightforward, but diagnosing it correctly matters. We explain what we find in plain terms before any work is approved.
Heat Pump Maintenance
Heat pumps benefit from the same seasonal check as furnaces, with the outdoor coil added to the list. San Lorenzo’s damp air coats coils with a fine film that reduces efficiency and can lead to compressor strain over time. We recommend a heating-season check before the December damp sets in, and a cooling-season check before the summer fog burns off.
Trusted Brands We Service in San Lorenzo
Our techs are factory-trained on nine major residential HVAC brands: Carrier, Trane, Lennox, Goodman, Rheem, York, Daikin, Bryant, and American Standard. For San Lorenzo specifically, we keep common Goodman, Rheem, and York parts stocked on local trucks, because those brands show up frequently in the 1990s and 2000s housing stock here. That means fewer second trips and faster turnaround when a flame sensor or ignitor fails. If we don’t have the part on the truck, we’ll tell you up front and get it ordered that day, with the repair scheduled in writing.
Common Furnace Repair Problems We See in San Lorenzo Homes
- Overnight no-heat lockouts from corroded flame sensors. Damp crawlspace and garage-installed furnaces collect moisture that glazes the flame sensor, and the unit locks out for safety. It’s the most common winter call here, and the fix is usually a cleaning or a $40 – $90 sensor replacement.
- Control board failures from humidity. The same moisture that fouls sensors also corrodes board connectors and solder joints. A short-cycling furnace that runs then shuts off repeatedly is often a board issue that needs a proper diagnostic, not a guess.
- Blower motor wear from oversized furnaces. Many San Lorenzo homes run a 1990s furnace under ductwork that was never load-calculated. Oversized tonnage means high static pressure and a blower motor that works harder than it should, shortening its life.
- Failed capacitors hiding until the cold snap arrives. Because winters here rarely force long runtimes, a weak capacitor can go unnoticed for months. Then the first genuinely cold night hits and the furnace won’t start. Same-day repair is available when that happens.
Pricing for Furnace Repair in San Lorenzo, CA
Here is what furnace work costs in San Lorenzo, in writing:
| Service | Price Range |
|---|---|
| Furnace repair (diagnostic + standard part/labor) | $150 – $700 |
| Furnace tune-up / seasonal safety check | $80 – $200 |
| AC repair (summer companion call) | $150 – $650 |
| AC installation (if repair-versus-replace points to new) | $3,500 – $7,500 |
Most San Lorenzo furnace repairs fall in the lower half of that $150 – $700 range. A flame sensor cleaning or ignitor replacement is typically $150 – $350. A gas valve or blower motor replacement pushes toward the upper end. What drives cost is the part, the labor time, and whether the unit is in a crawlspace or a garage. Estimates are free, and the price is in writing before we start. No exceptions.
We Also Serve Cities Near San Lorenzo
Our furnace repair and heat pump service extends to nearby Furnace Repair in San Lorenzo neighbors including Castro Valley, San Leandro, Union City, and Oakland. If you’re just outside San Lorenzo, call (361) 306-9515 and we’ll confirm coverage.
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 About Furnace Repair in San Lorenzo
In San Lorenzo, the usual cause is a glazed or corroded flame sensor, or a control board connector that’s failing from the damp crawlspace air. Overnight temperatures drop just enough that the burn cycle runs longer, the sensor fails to prove flame, and the board locks the unit out for safety. The fix is usually a sensor cleaning or replacement in the $150 – $350 range. Call (361) 306-9515 and we’ll diagnose it the same day.
Look at the repair cost against the remaining life of the furnace. If a $300 flame sensor fix keeps a 10-year-old furnace running safely for another five years, repair is the sound call. If the heat exchanger is cracked or the repair is approaching half the cost of a new system, replacement deserves a hard look. Our techs give you that honest math in writing, and we’re not paid on what we sell, so the recommendation is based on the unit, not a quota. Call (361) 306-9515 for a straight answer.
A load calculation, called a Manual J, sizes the furnace to your actual heating load rather than the old rule-of-thumb tons that most 1990s installs used. In San Lorenzo’s mild marine climate, the calculation usually comes back far lighter than what’s in the home now. That matters because an oversized furnace short-cycles, pushes high static pressure through undersized ductwork, and wears out blower motors and heat exchangers early. A proper load calculation changes the conversation from ‘same size as before’ to ‘what the house actually needs.’ We run one before recommending any replacement.
SEER2 is the updated efficiency standard for cooling equipment, and for heat pumps it also covers heating efficiency. It measures how much heating or cooling you get per watt of electricity, and the higher the number, the lower your utility bill for the same comfort. On a San Lorenzo heat pump quote, a SEER2 number like 15 or 16 on a modern system will cost more up front than a 14 but saves real money on PG&E bills over the years. We’ll show you the numbers side by side before you decide.
We repair heat pumps mini splits, and furnaces. Heat pump and mini split repair in San Lorenzo runs the same $150 – $700 band as furnace repair for diagnostic and standard parts and labor. Our techs are factory-trained on nine brands including Daikin, York, and Rheem, so the system you own is one we already service. Call (361) 306-9515 and tell us what’s happening. We’ll get it diagnosed.
Call Dalton Heating & Air for Furnace Repair in San Lorenzo
When your furnace quits or your heat pump stops heating, call (361) 306-9515. You’ll reach a live person, day or night. We’ll schedule a background-checked technician for San Lorenzo, arrive inside the stated window, and put the repair price in writing before any work starts. The repair is guaranteed in writing for a full year. If it fails in that time, we return at no charge. That’s The Garrison Standard, and it applies to every job we do in San Lorenzo.
Written by Marco Benitez, Owner at Dalton Heating & Air, serving San Lorenzo and the surrounding East Bay.