Heating & Cooling Services
For Homes & Commercial Properties
Reliable HVAC service when your furnace won't heat or your AC won't cool.
Repairs, maintenance, and installations for residential and commercial properties throughout Sonora and Tuolumne County.
Reliable Heating & Cooling Without the Runaround
What We Do
Furnace & Heating Repair
- Furnace troubleshooting and repair
- No heat / won't ignite issues
- Thermostat problems
- Airflow and blower issues
- Safety inspections
- Emergency heating repairs
When your heat goes out, we respond quickly to diagnose the problem and get you warm again.
Air Conditioning Repair
- AC won't cool or won't turn on
- Refrigerant leaks and recharging
- Compressor and condenser issues
- Fan motor problems
- Frozen coils
- Emergency cooling repairs
We fix what's broken and explain what failed so you understand what happened.
HVAC Installation & Replacement
- New furnace installation
- Air conditioner replacement
- Heat pump systems
- Complete system upgrades
- Ductwork modifications
- Thermostat upgrades (programmable, smart)
Replacing old equipment or installing new? We size systems correctly for your home and explain your options honestly.
Preventive Maintenance
- Annual furnace inspections and tune-ups
- AC system maintenance
- Filter changes and cleaning
- Safety checks and efficiency testing
- Seasonal system preparation
Regular maintenance catches problems early and extends equipment life. Most breakdowns happen because systems weren't maintained.
Ductwork & Air Quality
- Duct repairs and sealing
- Airflow balancing
- Vent and register service
- Basic air quality improvements
Poor airflow or uneven heating/cooling often comes from duct issues, not equipment failure.
Ductless Heating & Cooling (Mini-Splits)
- Bryant ductless system installation (single-zone & multi-zone)
- Replacements and upgrades
- Repairs and troubleshooting
- Maintenance and performance checks
- New additions, garages, bonus rooms, and older homes without ducts
Ductless systems are a high-efficiency way to heat and cool specific rooms without running new ductwork.
What Do You Need Help With?
Same-Day Service for No Heat & No AC
When your heating or cooling system fails, we respond quickly. Call now for same-day diagnosis and repair.
"New to Sonora and so thankful for the referral. J Hart is the best in town, not only for plumbing but also HVAC. Brian and JD were thorough, explained everything about both my furnace and water heater; they were professional and showed excellence in customer care."
Wendy Crowley
HVAC & Water Heater · 2025
Common Heating & Cooling Problems We Fix
If you're dealing with HVAC issues, here's what we see most often in Sonora-area homes and what you need to know.
Furnace Won't Heat
Furnace Won't Heat or Won't Turn On
Most common causes
Thermostat issues
Wrong setting, dead batteries, or faulty thermostat. We check this first.
Pilot light or ignition problems
Pilot won't stay lit or electronic ignition fails.
Dirty flame sensor
Buildup can shut the furnace down as a safety measure. Simple cleaning often fixes it.
Clogged filter
Restricted airflow can trigger safety shutoffs. Always check your filter first.
Blower motor failure
Heat at the furnace but not throughout the house.
Gas valve or control board
More serious failures that require parts replacement.
What we do
We diagnose systematically—starting with the common causes before moving to complex ones. We test components, identify the actual problem, and explain what needs to be fixed.
Repair vs. replacement
Simple repairs (thermostat, flame sensor, filters) are often $250–$500. Major component failures (blower motor, control boards, heat exchanger issues) can run $500+.
If your furnace is 15+ years old and needs an expensive repair, replacement often makes more financial sense. We'll give you honest guidance.
Why Choose J. Hart for HVAC Service?
Honest diagnostics
We identify the actual problem, not just sell the most expensive solution.
Clear pricing
You know what it costs before we start work.
Proper sizing
We calculate your actual heating/cooling needs, not guess.
Quality installations
Done right the first time, tested thoroughly.
Licensed & insured
CA Lic #459194 | NV Lic #77957
Mini-Split Systems
Ductless systems—often called mini-splits—are a high-efficiency way to heat and cool specific rooms without running new ductwork. They use an outdoor unit connected to one or more indoor air handlers through a small conduit.
Bryant Certified Ductless Pros
For new ductless installs, we prefer Bryant. We're a factory-authorized Bryant dealer and Bryant Certified Ductless Pros, so we can recommend the right setup and install it to manufacturer specs for long-term reliability.
Many ductless systems are heat pumps, so they can provide efficient heating in colder months too. For homes with existing ductwork, we also install Bryant air conditioners.
Choosing a New HVAC System: What Matters
Replacing your furnace or air conditioner? Here's what actually matters.
Sizing
Sizing Your HVAC System Correctly
Too small
Runs constantly and can't keep up.
Too large
Short cycling, poor humidity control, less comfort.
How we size systems
We calculate your home's heating and cooling load based on square footage, insulation, windows, ceilings, Sonora's climate/elevation, and ductwork capacity. We don't just match the old system's size.
Typical sizing for Sonora area homes
1,200–1,500 sq ft
2–2.5 ton AC
60,000–80,000 BTU furnace
1,500–2,000 sq ft
2.5–3.5 ton AC
80,000–100,000 BTU furnace
2,000–3,000 sq ft
3.5–5 ton AC
100,000–120,000 BTU furnace
Your actual needs depend on your specific home.
Free Estimates on HVAC Installation & Replacement
Whether you need a new furnace, AC, or complete system—we'll evaluate your home and provide an honest estimate at no cost.
Preventive Maintenance: Why It Matters
Most HVAC breakdowns are preventable. Regular maintenance catches problems before they leave you without heat or AC.
Furnace Maintenance (Fall)
- Inspect heat exchanger
- Test ignition and safety controls
- Clean/replace filters
- Check burners
- Inspect venting
- Check blower and performance
AC Maintenance (Spring)
- Clean condenser coils
- Check refrigerant levels
- Test capacitors/contactors
- Inspect fan motors
- Check drains
- Measure airflow and temperatures
Cost: Annual maintenance starts at $200 per system.
When to schedule: Furnace in fall, AC in spring.
Commercial HVAC Services
We handle heating and cooling for offices, retail spaces, and commercial buildings.
What we work on
Services
Emergency Heating & Cooling Service
Call us if you're dealing with:
More Reviews From Local Homeowners
This was the easiest, fastest, friendliest, and most professional contract job I've ever done! They helped me limp along on my old heater, then instal…
I work out of state most of the time and have tenants in my home in California. The water heater went out and the weather's been bad. J Hart was reall…
New to Sonora and so thankful for the referral. J Hart is the best in town, not only for plumbing but also HVAC. Brian and JD were thorough, explained…
Frequently Asked Questions
Every 1–3 months depending on the filter type, whether you have pets, and how much you run the system. A clean filter is the single easiest thing you can do to prevent problems.
Usually low airflow (dirty filter, blocked vents) or low refrigerant. Turn the system off, let it thaw, and check your filter. If it freezes again, call us—you likely have a refrigerant leak or airflow issue that needs professional diagnosis.
Furnaces typically last 15–20 years. Air conditioners last 10–15 years. Heat pumps last 10–15 years. Regular maintenance extends lifespan significantly.
If it's under 10 years old and the repair is minor, repair makes sense. If it's 15+ years old, needs frequent repairs, or requires a major component, replacement is usually the better investment. We'll give you an honest recommendation.
We can discuss payment arrangements for larger projects. Contact us to talk about your specific situation.
It depends on your home's square footage, insulation, windows, and layout. We perform a proper load calculation rather than guessing. Oversized systems are just as problematic as undersized ones.
Yes. We service, repair, and install heat pump systems including ductless mini-splits.
We service most major brands. For new installations, we recommend and install Bryant equipment as a factory-authorized dealer.
$185 flat fee (within 30 minutes of Sonora). It includes the diagnostic and the first half-hour of work. We'll explain pricing before any additional work begins.
Yes. We're Bryant Certified Ductless Pros. We install single-zone and multi-zone ductless systems for additions, garages, bonus rooms, and homes without existing ductwork.
Ready to Schedule?
We'll Call You Back Fast.
Fill out the form and we'll reach out to confirm your appointment. No holding, no runaround — just a real person who knows your trade area.
- Same-day appointments available Mon–Fri
- Upfront pricing — no surprises after the fact
- CA Lic #459194 · NV Lic #77957
- Hours: 7:30 AM – 4:00 PM, Mon–Fri