HVAC systems run for thousands of hours per year. Without basic maintenance, they end up needing $4,000 in repairs at year 12 instead of running quietly to year 17.
The homeowner schedule
Monthly: filter check
Most impactful HVAC habit. A dirty filter reduces airflow, allows dust into the coil, increases energy use, shortens life. Check monthly during heavy use; swap when visibly dirty.
Every 1-2 years: inside coil check
The indoor evaporator coil collects dust. Professional cleaning during tune-up handles this.
Seasonally: outdoor unit clear
2+ feet clearance on all sides. Remove leaves and debris from fins. Gentle hose spray. Don't pressure-wash.
Professional schedule
Once per year for single-mode systems, twice per year for combined systems (spring AC tune-up, fall heating tune-up).
A proper tune-up covers: refrigerant charge, coil cleaning, electrical connections, capacitor and contactor testing, combustion analysis (gas furnaces), heat exchanger inspection, blower motor service, drain line clearing, thermostat calibration.
Warning signs between visits
- Squealing on startup, banging, grinding, hissing
- Burning electrical smell — turn off, call
- Musty smell — possible mold
- Gas furnace + rotten egg = get out, call gas utility
- System running longer to reach setpoint
- Ice forming on outdoor unit in summer
- Higher utility bills with no other change
Maintenance contracts
Whether they're worth it depends on what's included. A contract with both tune-ups plus priority emergency service can pay for itself in one bad season. A contract that's just two basic tune-ups for more than they'd cost individually isn't worth it.