Wilmington / Wilmington
Wilmington has 71,727 residents (give or take 50) (ACS 2020-2024 5-year, table B01003, https://data.census.gov/table/ACSDT5Y2024.B01003?g=160XX00US1077580, checked 2026-10-19), about 6,583 people per square mile.
Wilmington is the city this door is named for; it covers 10.895 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 Wilmington that is 19801, 19802, 19805, 19806, 19809 (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).
Median household income in Wilmington is $58,671 (ACS 2020-2024 5-year, table B19013, https://data.census.gov/table/ACSDT5Y2024.B19013?g=160XX00US1077580, 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.
6,583 people per square mile puts Wilmington in suburban density, where the outdoor unit usually sits in a side yard and the noise is not an issue for neighbors.
10% of Wilmington homes are single-family detached, 11% are in two- to four-unit buildings and 25% are in buildings of five or more units (ACS 2020-2024 5-year, table B25024, https://data.census.gov/table/ACSDT5Y2024.B25024?g=160XX00US1077580, checked 2026-10-19).
52% of Wilmington homes are rented (ACS 2020-2024 5-year, table B25003, https://data.census.gov/table/ACSDT5Y2024.B25003?g=160XX00US1077580, checked 2026-10-19), so beside the 10% detached houses there is a real share of jobs where the landlord, not the resident, signs the quote.
Wilmington has 43 points fewer detached houses than New Castle County overall (53%) (ACS 2020-2024 5-year, table B25024, https://data.census.gov/table/ACSDT5Y2024.B25024?g=050XX00US10003, checked 2026-10-19).
52% of Wilmington homes are rented (ACS 2020-2024 5-year, table B25003, https://data.census.gov/table/ACSDT5Y2024.B25003?g=160XX00US1077580, 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.
Of the 31,655 occupied homes in Wilmington, 55% heat with natural gas, 5% with heating oil, 38% with electricity and 2% with propane (ACS 2020-2024 5-year, table B25040, https://data.census.gov/table/ACSDT5Y2024.B25040?g=160XX00US1077580, checked 2026-10-19).
Gas heats 55% of Wilmington against electricity at 38%, so most quotes here are a partial-home system that carries the shoulder seasons and the summer while the gas furnace handles the coldest nights, or a whole-home system when the house is ready for it.
Wilmington has 4 points less oil heat than New Castle County as a whole, where 9% of homes burn oil, and 6 points more electric heat than the county's 32% (ACS 2020-2024 5-year, table B25040, https://data.census.gov/table/ACSDT5Y2024.B25040?g=050XX00US10003, checked 2026-10-19).
No electric utility is on file for Wilmington on this door yet, so this page does not name one; the name on the bill decides which rebate path applies.
Wilmington has 35,514 housing units, 43% built before 1940 and 79% before 1980, with 13% built in 2000 or later (ACS 2020-2024 5-year, table B25034, https://data.census.gov/table/ACSDT5Y2024.B25034?g=160XX00US1077580, checked 2026-10-19).
Wilmington has 32 points more pre-1940 homes than New Castle County as a whole (11%) and 7 points fewer homes built after 2000 than the county's 20% (ACS 2020-2024 5-year, table B25034, https://data.census.gov/table/ACSDT5Y2024.B25034?g=050XX00US10003, checked 2026-10-19). An older stock means more insulation upgrades before the heat pump goes in.
The median Wilmington home was built in 1946 (ACS 2020-2024 5-year, table B25035, https://data.census.gov/table/ACSDT5Y2024.B25035?g=160XX00US1077580, checked 2026-10-19) and the median home has 5.3 rooms (ACS 2020-2024 5-year, table B25018, https://data.census.gov/table/ACSDT5Y2024.B25018?g=160XX00US1077580, checked 2026-10-19).
43% of Wilmington homes were built before 1940 and 79% before 1980 (ACS 2020-2024 5-year, table B25034, https://data.census.gov/table/ACSDT5Y2024.B25034?g=160XX00US1077580, checked 2026-10-19), so insulation is the first sizing question: an older home leaks more heat per square foot, and the installer runs a room-by-room heat-loss calculation to size the system for what the walls and windows actually hold in, not just the floor plan.
Heating design temperature: 11F. Source: ENERGY STAR Design Temperature Limit Reference Guide (2019 Edition), New Castle County row, 99% heating, PDF page 17 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 11F figure is the New Castle County cold-day number a Wilmington heat pump is sized against, so ask the installer to show the system's heating output at 11F, not at the milder rating-label temperature.
Ask whether the quote is whole-home or partial-home, because with 55% of Wilmington on gas and 38% already electric the two paths carry different rebate figures and different sizing.
Ask for the heat-loss calculation room by room; a Wilmington house from before 1940 (43% of the 35,514 units) rarely matches a square-footage rule of thumb.
The form on this page is the follow-up for Wilmington. The public number is the number the contractor quotes from.
No local contractor is named on this door for Wilmington yet. A request from this page goes to the first licensed shop that takes the door.