Heating and cooling is the biggest energy bill in most homes. The best HVAC contractors in Sunnyvale size the system correctly, seal the ducts and keep it running with honest maintenance instead of pushing a new unit every visit.
Picked by people who read the reviews.
Our review committee researched hvac contractors serving Sunnyvale and the surrounding area, read consumer reviews across the web, and settled on these five. We look at how many people have reviewed a company, what they say, and how the company holds up over time. We keep the full recipe to ourselves so it cannot be gamed. Google ratings shown are as of November 9, 2026. No company paid to be here, and none can. More on how we choose →
How to hire a hvac contractor in Sunnyvale
Ask for a load calculation (Manual J) before any replacement, not a guess by square footage.
Compare SEER2 ratings and the warranty on the compressor, not just the sticker price.
Check that the company is licensed and that its technicians are NATE certified or equivalent.
A good tune-up includes refrigerant pressures, airflow and electrical checks, not a filter swap.
HVAC Contractor questions, answered
How long does an air conditioner last?
About 12 to 15 years in hot climates with regular maintenance. Frequent repairs after year 10 usually mean replacement is the better buy.
Repair or replace?
A common rule: if the repair costs more than half the price of a new system and the unit is over 10 years old, replace it.
How often should filters be changed?
Every 1 to 3 months for standard 1-inch filters, more often with pets or allergies. Thicker media filters can go 6 to 12 months.
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