Delaware HVAC Climate Zones

Delaware is in IECC Climate Zone 4A (Mixed - Humid). Get accurate Manual J load calculations with official design temperatures and IECC requirements.

Find Your Delaware Climate Zone

Climate Zone in Delaware

Climate Zone 4A

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Mixed - Humid

Design Temperatures

Winter
13°F
Summer
91°F
Wet Bulb
75°F

IECC 2021 Requirements

Wall:R-20
Roof:R-49
Floor:R-19
Window U:0.32

Load Characteristic

Balanced Loads
humid Climate

Recommended Equipment for Delaware

Based on Climate Zone 4A (Mixed - Humid), here are typical HVAC equipment specifications for Delaware installations.

Heating Systems

Gas furnace (90%+ AFUE)
Heat pump
Typical AFUE Rating
92-96%

Annual Fuel Utilization Efficiency for Delaware furnaces

Cooling Systems

AC (14-16 SEER)
Heat pump
Typical SEER Rating
14-16 SEER

Seasonal Energy Efficiency Ratio for Delaware AC systems

Why Accurate Climate Data Matters in Delaware

Accurate Sizing

Delaware's climate zone data ensures proper equipment sizing. No more callbacks from oversized or undersized systems.

Code Compliance

Delaware building departments require IECC-compliant Manual J calculations. Our tool uses official Delaware climate data.

Energy Savings

Right-sized systems based on Delaware climate data reduce energy costs for homeowners and improve your reputation.

Get Free Manual J Calculations for Delaware

Upload your Delaware blueprint and get a professional Manual J load calculation with official climate zone data. First report is FREE.

Zone 4A design temps
IECC 2021 compliant
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