San Francisco, California HVAC Climate Zone

San Francisco is located in IECC Climate Zone 3C (Warm - Marine). Get accurate Manual J load calculations with official design temperatures for San Francisco.

Climate Zone
3C
Winter Design
41°F
Summer Design
81°F
ZIP Codes
27

San Francisco HVAC Contractors: Get Your Free Manual J Report

Climate Zone 3C requires precise load calculations. Upload your San Francisco blueprint and get a professional Manual J report in 60 seconds— first report is FREE. Pre-loaded with San Francisco's exact design temperatures (41°F winter / 81°F summer).

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Verify Your San Francisco ZIP Code

Enter your ZIP code to confirm it's in San Francisco and get climate zone details.

San Francisco covers 27 ZIP codes: 94102, 94103, 94104, 94105, 94107, 94108, 94109, 94110, 94111, 94112 and 17 more

San Francisco Design Temperatures

Official ASHRAE design temperatures for San Francisco, used for accurate Manual J load calculations.

Winter 99% Design Temp
41°F
Summer 1% Design Temp
81°F
Summer Wet Bulb
63°F

IECC Requirements for Zone 3C

Minimum insulation and window requirements for San Francisco per IECC 2021.

Wall Insulation:R-20
Roof/Ceiling:R-30
Floor Insulation:R-19
Window U-Factor:0.32
Window SHGC:0.4

Energy Code: 2022 Title 24

Recommended HVAC Equipment for San Francisco

Heating Systems

Gas furnace
Heat pump
Typical AFUE
90-95%

Cooling Systems

AC (often optional)
Heat pump
Typical SEER
14 SEER

Get Free Manual J Calculations for San Francisco

Upload your San Francisco blueprint and get a professional Manual J load calculation using official Zone 3C design temperatures. First report is FREE.

San Francisco design temps
Zone 3C compliant
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