San Francisco / South San Francisco
South San Francisco has 64,305 residents (give or take 49) (ACS 2020-2024 5-year, table B01003, https://data.census.gov/table/ACSDT5Y2024.B01003?g=160XX00US0673262, checked 2026-10-19), about 6,987 people per square mile.
South San Francisco is about 36 miles from the Census center point for San Francisco in a straight line and covers 9.204 square miles of land (Census 2024 Gazetteer internal points and land area, https://www2.census.gov/geo/docs/maps-data/data/gazetteer/2024_Gazetteer/, checked 2026-10-19).
The quote form takes a ZIP code; for South San Francisco that is 94080 (Census 2020 ZCTA to county subdivision and ZCTA to place relationship files, ZIP areas at least 20% inside the town, https://www2.census.gov/geo/docs/maps-data/data/rel2020/zcta520/tab20_zcta520_cousub20_natl.txt and https://www2.census.gov/geo/docs/maps-data/data/rel2020/zcta520/tab20_zcta520_place20_natl.txt, checked 2026-10-19).
6,987 people per square mile puts South San Francisco in suburban density, where the outdoor unit usually sits in a side yard and the noise is not an issue for neighbors.
Of the 21,838 occupied homes in South San Francisco, 61% heat with natural gas, 0% with heating oil, 33% with electricity and 2% with propane (ACS 2020-2024 5-year, table B25040, https://data.census.gov/table/ACSDT5Y2024.B25040?g=160XX00US0673262, checked 2026-10-19).
Gas heats 61% of South San Francisco against electricity at 33%, and a cold-climate heat pump sized for this market replaces the gas system outright, so the usual quote is a whole-home install.
South San Francisco has about the San Mateo County oil share of 0% and 1 points more electric heat than the county's 32% (ACS 2020-2024 5-year, table B25040, https://data.census.gov/table/ACSDT5Y2024.B25040?g=050XX00US06081, checked 2026-10-19).
South San Francisco has 23,515 housing units, 7% built before 1940 and 70% before 1980, with 15% built in 2000 or later (ACS 2020-2024 5-year, table B25034, https://data.census.gov/table/ACSDT5Y2024.B25034?g=160XX00US0673262, checked 2026-10-19).
South San Francisco has 3 points more homes built after 2000 than the county's 12% (ACS 2020-2024 5-year, table B25034, https://data.census.gov/table/ACSDT5Y2024.B25034?g=050XX00US06081, checked 2026-10-19).
The median South San Francisco home was built in 1965 (ACS 2020-2024 5-year, table B25035, https://data.census.gov/table/ACSDT5Y2024.B25035?g=160XX00US0673262, checked 2026-10-19) and the median home has 4.9 rooms (ACS 2020-2024 5-year, table B25018, https://data.census.gov/table/ACSDT5Y2024.B25018?g=160XX00US0673262, checked 2026-10-19).
58% of South San Francisco homes are single-family detached, 6% are in two- to four-unit buildings and 24% are in buildings of five or more units (ACS 2020-2024 5-year, table B25024, https://data.census.gov/table/ACSDT5Y2024.B25024?g=160XX00US0673262, checked 2026-10-19).
41% of South San Francisco homes are rented (ACS 2020-2024 5-year, table B25003, https://data.census.gov/table/ACSDT5Y2024.B25003?g=160XX00US0673262, checked 2026-10-19), so beside the 58% detached houses there is a real share of jobs where the landlord, not the resident, signs the quote.
41% of South San Francisco homes are rented (ACS 2020-2024 5-year, table B25003, https://data.census.gov/table/ACSDT5Y2024.B25003?g=160XX00US0673262, checked 2026-10-19), so the market splits between resident-led jobs where the occupant picks the system and landlord-led jobs where they do not, and the rebate paperwork differs.
70% of South San Francisco homes were built before 1980 and only 15% in 2000 or later (ACS 2020-2024 5-year, table B25034, https://data.census.gov/table/ACSDT5Y2024.B25034?g=160XX00US0673262, checked 2026-10-19), so most of the stock predates modern insulation codes; the installer's heat-loss calculation, not a square-footage rule, decides the tonnage.
No electric utility is on file for South San Francisco on this door yet, so this page does not name one; the name on the bill decides which rebate path applies.
LADWP Consumer Rebate Program heat pump HVAC, run by LADWP, is a live program for California addresses and publishes its terms without one headline figure (registry row 24 verified 2026-10-14, https://www.ladwp.com/residential-services/assistance-programs/consumer-rebate-program, checked 2026-10-16); confirm eligibility for the South San Francisco address before counting it. With 33% of South San Francisco homes already on electric heat and 63% on gas, oil or propane, the row that applies depends on the name on the electric bill and the fuel coming out.
Median household income in South San Francisco is $136,578 (ACS 2020-2024 5-year, table B19013, https://data.census.gov/table/ACSDT5Y2024.B19013?g=160XX00US0673262, checked 2026-10-19); many state and utility heat pump rebate programs set higher incentive tiers for income-qualifying households, so the household income on the application, not the town median, decides which level applies.
Heating design temperature: 29F. Source: ENERGY STAR Design Temperature Limit Reference Guide (2019 Edition), San Mateo County row, 99% heating, PDF pages 11 to 13 of 141 (Revised 11/11/2020), https://www.energystar.gov/sites/default/files/Design%20Temperature%20Limit%20Reference%20Guide%20(2019%20Ed)%20-%20ENERGY%20STAR%20Single-Family%20New%20Homes_Rev11.pdf, fetched 2026-10-19, 99%.
That 29F figure is the San Mateo County cold-day number a South San Francisco heat pump is sized against, so ask the installer to show the system's heating output at 29F, not at the milder rating-label temperature.
Ask whether the quote is whole-home or partial-home, because with 61% of South San Francisco on gas and 33% already electric the two paths carry different rebate figures and different sizing.
Ask for the heat-loss calculation room by room; the median South San Francisco home has 4.9 rooms and was built around 1965, and the count of heads and the tonnage follow the rooms and the insulation, not the square footage.
The form on this page is the follow-up for South San Francisco. The public number is the number the contractor quotes from.
No local contractor is named on this door for South San Francisco yet. A request from this page goes to the first licensed shop that takes the door.