What Size AC & BTU for a 4,000 Sq Ft House?
Heating and air conditioning capacity sizing for a 4,000 square foot residence located in Zone 2: Southeast & Central Warm. Engineered to avoid short-cycling while ensuring full sensible and latent humidity control.
Air Distribution & Electrical Requirements
Custom BTU EngineHot summers with mild to moderate winters (NC, SC, TN, OK, Northern TX, Southern CA).
Frequently Asked HVAC Sizing Questions
What size AC or heat pump do I need for a 4,000 sq ft house in Zone 2: Southeast & Central Warm?
For a 4,000 square foot home located in Zone 2: Southeast & Central Warm, an ACCA Manual J load calculation typically specifies a 5-Ton system (60,000 BTU/hr of cooling capacity).
How much airflow (CFM) and what duct size is required?
A 5-Ton HVAC condenser requires approximately 2,000 CFM of total airflow (based on 400 CFM per ton). Your main supply plenum trunk line should be sized at minimum 20" Round Main Trunk or Dual 14" Branch Trunks at 0.10 in. w.c. friction rate per ACCA Manual D standards.
Why is oversizing an air conditioner bad for a 4,000 sq ft home?
Installing an oversized unit causes 'short-cycling'—the compressor cools the air too rapidly without running long enough to condense humidity out of the air. This results in a cold, clammy living space and increases wear on the compressor capacitor and contactor.
What heating capacity is recommended for this climate?
In Zone 2: Southeast & Central Warm, winter design conditions require approximately 60,000 BTU/hr of heating capacity via a modern variable-speed heat pump or high-efficiency condensing gas furnace.