Your HVAC
How heat pumps work in New Orleans
Understand how an air-source heat pump cools and heats, plus the controls, backup heat, sizing, and bill questions that matter locally.
Cooling looks like ordinary AC
In cooling mode, indoor refrigerant absorbs heat and the outdoor unit rejects it. The indoor coil also condenses moisture when its surface is below the air’s dew point. Ducts or indoor mini-split heads distribute the conditioned air.
Heating reverses the direction
A reversing valve changes refrigerant flow so the outdoor coil absorbs heat and the indoor coil releases it. The unit moves heat rather than creating all heat through electrical resistance. DOE describes heat pumps as an energy-efficient alternative to separate furnaces and air conditioners in moderate climates (DOE).
As outdoor temperature falls, available heating capacity and efficiency vary by model. The system may use staged compressors, defrost operation, and supplemental heat. Equipment data—not a generic claim—should show capacity at the conditions used for design.
Understand backup heat and defrost
Many ducted heat pumps have electric resistance heat strips. Controls can use them when the heat-pump capacity is insufficient, during some defrost events, after a large thermostat increase, or in emergency-heat mode. Resistance heat can draw much more electric power than compressor-only heating. The exact sequence is system-specific.
During defrost, the outdoor fan may stop, steam may rise, and supplemental heat may temper indoor air. A brief, controlled defrost is normal. Persistent heavy ice or loss of heating is not something to diagnose by forcing controls.
Questions for a New Orleans proposal
- Was heating and cooling load calculated?
- What are the system’s heating capacity and efficiency at relevant outdoor temperatures?
- Is backup heat included, and what electrical service does it require?
- How are staging, thermostat lockouts, and defrost configured?
- Are the ducts and return paths adequate?
- How will humidity performance be commissioned in cooling mode?
- If replacing gas heat, how do current fuel and electric costs affect operating scenarios?
ENERGY STAR recommends Manual J sizing and matched equipment selection, and notes that variable-capacity equipment can adjust operation across changing loads (ENERGY STAR).
Heat pump versus “AC with electric heat”
Both may use the same ducts and look similar at the thermostat. A heat pump can move heat with the compressor. A straight-cool AC paired only with electric resistance heat cannot. Confirm the model and control configuration; do not infer the system type from the outdoor cabinet alone.
Sources
- DOE — Heat pumps, accessed 8/12/2026
- DOE — Consumer central air conditioners and heat pumps, accessed 8/12/2026
- ENERGY STAR — Clean heating and cooling, accessed 8/12/2026