Heating and air conditioning repair in San Diego
Our guide to heating and air conditioning repair covers how the job works. Below: the San Diego numbers a HVAC contractor looks at, with sources.
San Diego housing, by the numbers
1979 is the median construction year for homes in San Diego (Census ACS). By median year built, homes here are older than in 19 of the 56 other cities we cover. A house from that era may have had its system replaced more than once; the ducts usually stay.
Source: Census ACS
Source: Census ACS
In San Diego, owner-occupied homes make up about 47% of occupied housing. That is 251,100 of 530,412 households. Of the 56 other cities in this network, 24 have a lower share of owner-occupied homes. If you rent, your lease likely puts heating and cooling repairs on the owner.
Source: Census ACS
Source: Census ACS
The leading home heating fuel in San Diego is utility gas, at about 51% of occupied homes. Other fuels: electricity 39%, bottled or tank gas 1%, fuel oil or kerosene under 1%. Homes on that fuel need a contractor licensed and equipped for it.
Source: Census ACS
Source: Census ACS
What the weather asks of a system in San Diego
Cooling load in San Diego comes to roughly 1,019 cooling degree days in a normal year (NOAA 1991-2020 normals). Measured at the San Diego Montgomery Fld (CA) station. The cooling load here is higher than in 18 of the 56 other cities we cover. More cooling degree days means more run hours, which is where worn capacitors and dirty coils show up first.
Source: NOAA normals
Source: NOAA normals
By the NOAA 1991-2020 normals, winters in San Diego add up to about 1,320 heating degree days. Measured at the San Diego Montgomery Fld (CA) station. The heating load here is higher than in 8 of the 56 other cities we cover. Heating load like that decides whether a heat pump alone is enough or a furnace backup makes sense.
Source: NOAA normals
Source: NOAA normals
Near San Diego the high reaches 90 F or more on about 16 days in a normal year. Of the 54 other cities in this network, 12 have a lower number of 90 F days.
Source: NOAA normals
Source: NOAA normals
When the weather tests homes in San Diego
FEMA's National Risk Index rates heat wave risk in San Diego County, CA as relatively high. 30 of the 55 other cities we cover sit in counties with the same heat wave rating. Extended heat is hard on compressors that are already weak.
Source: FEMA risk index
Source: FEMA risk index
The cold wave risk for San Diego County, CA is rated very low in FEMA's National Risk Index. The same cold wave rating applies in 4 of the 53 other cities in this network. Frozen weather is when a furnace that limped through fall finally quits.
Source: FEMA risk index
Source: FEMA risk index
In California, HVAC contractors are licensed by the Contractors State License Board (CSLB); status can be checked on the agency's official lookup page.
Source: Contractors State License Board (CSLB) (California) · Contractors State License Board (CSLB) license information
Source: Contractors State License Board (CSLB) (California) · Contractors State License Board (CSLB) license information
Sources, checked October 2026
Local offices and rules in San Diego
San Diego applies the 2025 California Building Standards Code to all projects with applications submitted on or after January 1, 2026, including the California Building, Residential, Mechanical, Plumbing and Green Building Standards Codes.
Source: www.sandiego.gov. Checked October 2026.
Source: www.sandiego.gov. Checked October 2026.
The California Building Standards Commission lists the 2025 Title 24 edition, including Part 4 (California Mechanical Code) and Part 6 (California Energy Code), as effective January 1, 2026.
Source: www.dgs.ca.gov. Checked October 2026.
Source: www.dgs.ca.gov. Checked October 2026.
For single-family homes, townhomes and duplexes, San Diego offers a Simple No-Plan Mechanical Permit covering forced air unit or A/C installations, exhaust fans and furnace replacements, applied for online through Accela and usually issued within two business days.
Source: www.sandiego.gov. Checked October 2026.
Source: www.sandiego.gov. Checked October 2026.
SDG&E states that the Golden State Rebates Program's retail rebate offerings have ended, and lists a customer line for questions about the closure.
Source: www.sdge.com. Checked October 2026.
Source: www.sdge.com. Checked October 2026.
San Diego Gas & Electric (SDG&E) delivers electricity in San Diego, though its site notes it is not the only electricity provider in San Diego and Orange County.
Source: www.sdge.com. Checked October 2026.
Source: www.sdge.com. Checked October 2026.
If you smell gas, leave the house and call your gas utility from outside. Keep a working carbon monoxide alarm near the bedrooms, and do not open a furnace cabinet that is running.
Common jobs
