AC & heating repair · Hazelwood, Missouri
AC repair and HVAC service in Hazelwood, MO
AC quit, heat pump struggling, or a system near the end of its life? In Hazelwood, 30% of homes heat with electricity[1] and half were built before 1970. Request service from HVAC contractors working here. Hazelwood, in St. Louis County — ZIPs 63042, 63031, 63044, counts 24,849 residents (2025 estimate)[2].
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Hazelwood at a glance for HVAC
- Population (2025 est.)
- 24,849[2]-2.4% since 2020
- County
- St. Louis[2]
- Land area
- 16.0 sq mi[3]
- Homes heated with electricity
- 30%[1]the 7th-highest share of the 15 St. Louis–area suburbs we cover
- Homes heated with utility gas
- 67%[1]plus 3% propane/LP
- Heat & excessive-heat days, st. louis zone
- 21[4]2016–2025
- Winter-storm & freeze days, st. louis zone
- 12[4]2016–2025; heating demand and freeze-related furnace failures
- Lightning-damage reports within 10 mi
- 0[4]2016–2025; power surges damage HVAC control boards
- Damaging-wind reports within 10 mi
- 75[4]2016–2025; wind-blown debris damages outdoor condenser units
- Homes built before 2000
- 91%[1]of 12,379 housing units
- Median year built
- 1970[1]the 5th-oldest of the 15 St. Louis–area suburbs we cover
What the local data means for HVAC in Hazelwood
Hazelwood is one of the most established suburbs tracked here — 24,849 people (2025 estimate), down just 2.4% since 2020[2]. On the map that's 16.0 square miles holding 1,549 residents per square mile, the 13th densest of the suburbs here; it sits entirely in St. Louis County, with ZIP codes 63042, 63031, 63044[3].
Only 1% of Hazelwood's homes were built in 2010 or later, against 91% before 2000[1] — most systems here are past any builder warranty, and older homes often keep their original ductwork.
Hazelwood is split across 3 ZIP codes: 63042 (63% of the city's land), 63031 (20% of the city's land), 63044 (15% of the city's land)[5].
Nearest of the other suburbs we track: Florissant (3.7 mi E), St. Charles (6.4 mi W) and Maryland Heights (6.8 mi SW)[3].
30% of occupied Hazelwood homes heat with electricity, 67% with utility gas and 3% with propane[1] — the 7th-highest electric share of the 15 St. Louis–area suburbs we cover; nearby, Florissant (15%), St. Charles (35%), and Maryland Heights (38%) heat electrically. Gas heat means a furnace plus a separate AC condenser.
St. Louis County forecast zone, 2016–2025: 21 heat or excessive-heat days (latest Aug 16, 2025) and 12 winter-storm or hard-freeze days[4]. Nearby: Florissant (21), St. Charles (14), and Maryland Heights (21).
Storm exposure for HVAC hardware: 0 lightning-damage reports within 10 miles; 75 damaging-wind reports within 10 miles in 2016–2025[4]. Most recent: Aug 17, 2025, 4.0 miles from the city center.
91% of Hazelwood's 12,379 housing units were built before 2000 and 1% since 2010[1] (pre-2000 share nearby: Florissant (97%), St. Charles (72%), and Maryland Heights (88%)). Older homes often keep original ductwork.
Measured against the 15 suburbs on this site, Hazelwood records the 2nd-lowest share of homes built since 2010 (1%)[1].
How air moves through a central system
How the loop runs: return duct to filter to air handler to supply ducts. A dirty filter slows everything downstream.
Hazelwood storm calendar
Within 10 miles of Hazelwood, 2016–2025: 75 damaging-wind reports[4]. Peak: spread out; March, May, and July held 52%. Busiest year 2025 (13). Busiest month March 2025 (8). Latest: damaging-wind report, Aug 17, 2025, 4.0 mi out.
| Month | Damaging wind | Lightning | All |
|---|---|---|---|
| Feb | 1 | – | 1 |
| Mar | 11 | – | 11 |
| Apr | 9 | – | 9 |
| May | 12 | – | 12 |
| Jun | 11 | – | 11 |
| Jul | 16 | – | 16 |
| Aug | 11 | – | 11 |
| Sep | 1 | – | 1 |
| Nov | 1 | – | 1 |
| Dec | 2 | – | 2 |
Finding HVAC help around Hazelwood
Your request reaches AC & heating repair contractors who serve Hazelwood (ZIP codes 63042, 63031, 63044).
Before reaching out: repair or replace? what a good hvac visit covers
The Hazelwood numbers behind this page
| Measure | Hazelwood | Median of 15 | Difference |
|---|---|---|---|
| Propane / LP heat | 3.0% | 1.4% | 2 pts higher |
| Built 2010 or later | 1% | 6% | 5 pts lower |
| Built before 2000 | 91% | 83% | 8 pts higher |
| Damaging-wind reports (10 mi) | 75 | 72 | 3 more |
| Utility-gas heat | 67% | 69% | 2 pts lower |
| Electric heat | 30% | 29% | 1 pts higher |
| Median year built | 1970 | 1977 | 7 years older |
Biggest gaps first. Medians are middle values across the St. Louis–area suburbs we cover, drawn from the same sources.
| City | Heat days | Lightning reports | Damaging-wind reports |
|---|---|---|---|
| Hazelwood | 21 | 0 | 75 |
| Florissant 3.7 mi | 21 | 0 | 57 |
| St. Charles 6.4 mi | 14 | 0 | 68 |
| Maryland Heights 6.8 mi | 21 | 1 | 90 |
| University City 9.6 mi | 21 | 2 | 92 |
| St. Peters 11.2 mi | 14 | 0 | 75 |
| Date | Wind | Distance |
|---|---|---|
| Aug 17, 2025 | 58 mph | 4.0 mi |
| Jul 6, 2025 | 75 mph (est.) | 8.8 mi |
| Jun 17, 2025 | 58 mph (est.) | 4.1 mi |
| Jun 17, 2025 | 58 mph (est.) | 6.4 mi |
| May 16, 2025 | 60 mph | 9.6 mi |
| Mar 14, 2025 | 86 mph (est.) | 6.9 mi |
| Main heating fuel | Homes | Share | Margin of error |
|---|---|---|---|
| Utility gas | 7,567 | 66.7% | ±571 |
| Electricity | 3,388 | 29.9% | ±580 |
| Bottled or tank gas (propane, butane, etc.) | 341 | 3.0% | ±231 |
| No fuel used | 31 | 0.3% | ±47 |
| Other fuel | 17 | 0.1% | ±33 |
| Built | Units | Share | Margin of error |
|---|---|---|---|
| 2020 or later | 0 | 0.0% | ±23 |
| 2010 to 2019 | 177 | 1.4% | ±160 |
| 2000 to 2009 | 904 | 7.3% | ±312 |
| 1990 to 1999 | 1,113 | 9.0% | ±381 |
| 1980 to 1989 | 2,067 | 16.7% | ±360 |
| 1970 to 1979 | 1,901 | 15.4% | ±458 |
| 1960 to 1969 | 3,840 | 31.0% | ±493 |
| 1950 to 1959 | 1,590 | 12.8% | ±318 |
| 1940 to 1949 | 668 | 5.4% | ±432 |
| 1939 or earlier | 119 | 1.0% | ±98 |
ACS 2020–2024 estimates; margins of error are the Census Bureau's 90% intervals.
| Measure | Value |
|---|---|
| Housing units | 12,379 |
| Detached single-family | 7,427 (60%) |
| Occupied homes | 11,344 |
| Owner-occupied | 6,706 (59%) |
| Renter-occupied | 4,638 (41%) |
| Median home value | $167,400 |
ACS 2020–2024 estimates.
| ZIP (ZCTA) | Share of Hazelwood's land | Share of the ZIP inside the city |
|---|---|---|
| 63042 | 63% | 98% |
| 63031 | 20% | 22% |
| 63044 | 15% | 14% |
Dated heat and freeze records for the ST. LOUIS forecast zone: see the county list.
HVAC questions from Hazelwood homeowners
Are heat pumps common in Hazelwood?
30% of Hazelwood homes heat with electricity[1], which means a heat pump or electric resistance heat.
How old are Hazelwood's homes — and their HVAC systems?
The median home dates to 1970, and 1% were built in 2010 or later[1]. Your own system may have been replaced since — the outdoor unit's data plate shows when it was made.
Which Hazelwood ZIP codes are covered?
63042, 63031, and 63044[5], St. Louis County. Nearby pages: Florissant (3.7 mi), St. Charles (6.4 mi), and Maryland Heights (6.8 mi)[3].
A lot of Hazelwood homes predate 1980 — what does that mean for HVAC equipment work?
66% of Hazelwood's housing units were built before 1980, 19.2% before 1960[1] — the 5th-highest share of the 15 St. Louis–area suburbs we cover. The ductwork in an older house is often original even when the equipment is not — ask for a duct leakage check with any replacement quote.
I rent in Hazelwood. Who arranges the repair?
41% of occupied Hazelwood homes are rented[1], the 3rd-highest share of the 15 St. Louis–area suburbs we cover. Tell your landlord or property manager in writing first; your lease says who arranges repairs.
My Hazelwood home runs on propane — does that matter?
3.0% of occupied Hazelwood homes heat mainly with bottled, tank or LP gas[1], at least twice the median share of the suburbs we cover (1.4%). Homes on propane need a contractor who works on LP appliances — mention it when you request service.
Sources
- Census ACS 2020–2024 5-year (keyless bulk)
- Census population estimates, Vintage 2025
- Census Gazetteer 2025
- NOAA Storm Events Database
- Census 2020 ZCTA–place file
Data pulled Sep 28, 2026. Full citations and method.