Furnace Installation in Florissant, MO
A new furnace here will run from October through April every year. Tell us about the house, and a licensed contractor who covers St. Louis County will get in touch.
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Seven months of heating in Florissant
Your furnace runs from October through April here, seven months of the year. Winter nights average 26°F, and most homes in the area heat with gas, so the furnace is doing steady work most of the year, not just on the coldest days.
A new gas furnace installed today has to reach at least 80 percent AFUE, the federal minimum for non-weatherized units. Missouri also sees its share of winter storms and wind, and enough power outages that a good number of households lose power for a day or more. If your furnace has electric ignition, it will need power to start even when the gas line is fine.
- 7 months
- October through April, your furnace is on duty
- 26°F
- the average winter night it heats against
- 75%
- of homes here heat with gas, so most furnaces here burn gas
- 80% AFUE
- the federal minimum any new unit must meet
NOAA nClimDiv, 1991–2020 normals
A high-efficiency gas furnace would save about $160 a year to run in St. Louis County compared with a gas furnace.
Estimates for a typical St. Louis County home, from EIA household energy data, Missouri fuel prices and NOAA climate normals. Your home will differ.
- What size furnace does my house need?
- It depends on your square footage, your insulation, your ceiling height, and how much sun and shade the house gets, so there's no single number that fits every home. A furnace that's too big will short cycle, heating the house in bursts and wearing out faster. One that's too small will run constantly all winter and still struggle to keep up on the coldest nights, when lows here average 26°F. A contractor works this out with a load calculation on your actual house, not a chart based on square footage alone.
- How do I know it's time to replace my furnace?
- Age is one sign, especially if repairs are getting more frequent or more expensive. Uneven heat between rooms, a furnace that runs longer than it used to, or a yellow flame instead of blue all point the same way. Homes here need heat from October through April, so a furnace that's struggling doesn't get much of a break to fail gracefully. A contractor can tell you whether what you're seeing is a repair or the start of the end.
- Is a high-efficiency furnace worth it?
- It depends on how long you plan to stay in the house and how much you run the furnace. Homes here need heat seven months of the year, October through April, so a furnace that's more efficient gets a lot of chances to make that difference back. Every non-weatherized gas furnace made since November 2015 has to reach at least 80 percent AFUE, so even a standard replacement today burns less gas per hour of heat than an older unit did. Higher-efficiency models go further than that minimum, but they also cost more up front and some need different venting. A contractor can walk you through the models that fit your house and what each one would mean for your setup.