Types of Air Conditioners
Common types include window units, portable units, ductless mini-splits, and central air systems. Your choice depends on space, budget, and whether you rent or own.
Key Specifications to Consider
- BTU/Capacity: Match cooling capacity to room size. Undersized units run constantly; oversized units short-cycle and waste energy.
- SEER/EER/CEER: Higher efficiency ratings reduce operating costs. Look for Energy Star certification.
- Noise (dB): Bedrooms and offices benefit from quieter units (under ~55 dB).
- Voltage & Amperage: Ensure your circuit can handle the load (common: 115V for small units, 230V for larger).
- Refrigerant: Modern systems use R-32 or R-410A; phaseouts may affect service costs and availability.
Sizing Guide (Room Units)
- Up to 150 sq ft: ~5,000–6,000 BTU
- 150–300 sq ft: ~7,000–8,000 BTU
- 300–450 sq ft: ~10,000 BTU
- 450–700 sq ft: ~12,000–14,000 BTU
- Consider sun exposure, ceiling height, occupants, and heat-generating appliances; adjust BTU upward as needed.
Installation Tips
- Seal gaps around window units and portable exhaust hoses to prevent hot air infiltration.
- Mini-splits and central systems should be installed by licensed HVAC pros; proper line set length, vacuum, and charge are critical.
- Ensure adequate drainage/condensate management to avoid water damage.
Maintenance Basics
- Clean or replace filters every 1–3 months during heavy use.
- Keep coils and fins clean; gently straighten bent fins with a fin comb.
- Maintain clear airflow around outdoor condensers (at least 2–3 feet of clearance).
- Schedule annual professional service for mini-splits and central systems.
Cost and Efficiency Tips
- Use programmable or smart thermostats and set reasonable setpoints (e.g., 76–78°F when home).
- Improve home envelope: shade windows, close blinds, and seal leaks to reduce cooling load.
- Run ceiling fans to improve comfort at slightly higher setpoints.
- Consider utility rebates and tax credits for high-efficiency systems.
Troubleshooting Quick Checks
- Unit won’t cool: verify mode (cool), setpoint below room temp, clean filter, and unobstructed airflow.
- Ice on coils: likely low airflow or low refrigerant; turn off and let thaw, clean filter; call a pro if it recurs.
- Water leaks: check drain lines/pans and ensure proper tilt on window units.
- Breaker trips: check dedicated circuit requirements and amperage; persistent trips need an electrician/HVAC tech.
When to Replace vs. Repair
- Units over 10–15 years old with frequent issues or high energy bills may be better replaced.
- Rule of $5,000: multiply repair cost by unit age; if over $5,000, replacement often makes sense.