Furnace replacement in Air Force Academy, CO with sizing, venting and airflow done right
A new furnace is only as good as the calculation behind its size and the ductwork it connects to. We look at the whole air system so the upgrade actually shows up as warmer rooms and lower bills.
Click Here To Call (888) 418-3681- Manual J load sizing
- Venting inspected
- Airflow measured at startup
Deciding that it is time for a new furnace
Most furnaces give years of warning before they fail for good. Ignition problems become more frequent, the blower grows louder, rooms farthest from the unit never quite get warm, and repair bills start arriving every winter. None of these alone proves that replacement is necessary, but together they describe a machine that is costing more to keep running each year.
The one condition that ends the discussion is a compromised heat exchanger. The heat exchanger keeps combustion gases separate from the air circulating through your home. Cracks or holes can allow those gases, including carbon monoxide, to mix into the airstream. When a heat exchanger has failed, the furnace should be shut down, and replacing that part alone on an older unit rarely makes financial sense.
Efficiency is the other major factor. An older furnace may convert considerably less of its fuel into usable heat than a modern high-efficiency model, which captures additional heat from its exhaust using a secondary heat exchanger. Over years of winters, that difference in fuel use adds up, and it is worth weighing alongside repair costs when deciding what to do.
Replacement also opens the door to comfort improvements that are difficult to retrofit. Two-stage and modulating gas valves, variable-speed blowers and communicating thermostats all make heat delivery quieter and more even. Pairing the furnace decision with a look at your ducts, through our Duct Sealing work where leaks are found, often makes a larger difference to comfort than the furnace upgrade alone.
Signs a furnace is nearing the end
If several of these describe your system, it is worth getting a replacement estimate before the next cold snap.
- Yellow or flickering burner flamesGas burners should burn mostly blue and steady. Lazy yellow flames can signal poor combustion, a dirty burner or a flame disturbed by air leaking through a damaged heat exchanger.
- Carbon monoxide alarm activationsLeave the house, call emergency services, and do not run the furnace until it has been inspected. Every home with fuel-burning appliances should have working CO alarms.
- Frequent ignition failuresHot surface igniters and flame sensors wear out, but repeated lockouts can also come from failing control boards and gas valves as a furnace ages.
- Rising heating billsWhen fuel costs climb while your usage and rates stay similar, the furnace may be losing efficiency through worn burners, blower problems or duct losses.
- Loud banging, rumbling or screechingDelayed ignition, loose blower wheels and failing motor bearings all make noise before they fail completely.
- Rust and corrosion inside the cabinetCorrosion on the heat exchanger, burners or the base of a high-efficiency unit often traces back to condensate or venting problems.
What happens during a furnace replacement
A standard swap in an existing location usually takes a single day.
Load calculation
The heat loss of the home is calculated from its size, insulation, windows and orientation, so the new furnace is matched to the house rather than copied from the old nameplate.
Duct and venting inspection
We measure static pressure in the existing ducts and inspect the flue or vent path. High-efficiency furnaces vent through plastic pipe and produce condensate that needs a drain.
Removal
Gas and power are shut off, the old furnace is disconnected and removed, and the area is cleaned before the new unit goes in.
Installation
The new furnace is set level, connected to the supply and return plenums, piped for gas with a sediment trap, wired and vented according to the manufacturer and local code.
Startup and testing
Gas pressure, temperature rise across the heat exchanger, static pressure and combustion readings are checked and written down, and you are shown the filter location and thermostat settings.
Variables that affect furnace replacement pricing
The efficiency level and staging of the furnace affect the equipment cost. A single-stage 80 percent unit costs less upfront than a two-stage or modulating high-efficiency model, while the higher-efficiency furnace uses less fuel every winter. The right choice depends on how long you plan to stay in the home, fuel prices and how much comfort improvement matters to you.
Installation conditions add or remove work. Converting from a chimney-vented furnace to a high-efficiency model means new vent piping and a condensate drain. Undersized return ducts may need enlarging so the new blower is not starved of air. Attic and crawlspace installations take more time than basements. Each of these is identified during the assessment and listed separately on your proposal.
The case for measuring static pressure
Static pressure is to a duct system what blood pressure is to a body. Every furnace blower is designed to move a certain volume of air against a certain amount of resistance. When ducts are undersized, filters are too restrictive or returns are missing, resistance climbs, airflow drops, and the furnace runs hotter than it should, tripping limit switches and cracking heat exchangers years before their time.
Many replacement furnaces are installed without anyone measuring static pressure, which means the same airflow problem that damaged the old furnace goes on to damage the new one. We measure it before and after installation. If the numbers are high, we explain the duct changes that would bring them down, which often have a larger effect on comfort than the furnace itself.
Planning for cooling at the same time
The furnace blower also moves air for central air conditioning, and the indoor coil for the air conditioner sits on top of the furnace. If your cooling system is nearing replacement too, doing both at once ensures the blower, coil and outdoor unit are matched and avoids paying for labor to disconnect and reconnect the coil twice.
If the air conditioner is relatively new, the new furnace can usually be paired with it. We verify that the blower can deliver the airflow your coil needs. For homes considering electrification, a heat pump paired with a gas furnace, known as a dual-fuel system, is another option, and our Heat Pump Installation page explains how those systems split the heating load.
Furnace replacement questions
AFUE measures how much fuel becomes usable heat. High-efficiency furnaces commonly rate 95 percent or higher, while standard models rate around 80 percent. In colder climates and larger homes, the higher-efficiency option typically pays back faster. We show you estimated operating cost differences for your home so the choice is based on numbers.
In most cases, yes. The part itself may be covered by a manufacturer warranty on newer units, but the labor to replace it is substantial. On a furnace that is already well into its service life, putting that money toward a new furnace is usually the better investment.
A single-stage furnace runs at full output every time it turns on. A two-stage furnace runs at a lower output most of the time and only uses full output on the coldest days. The result is longer, quieter cycles with more even temperatures throughout the home.
Not always, but a two-stage or modulating furnace needs a compatible thermostat to use its lower stages properly. Some communicating systems require the manufacturer's own control. We confirm compatibility before installation.
With annual maintenance, clean filters and correct airflow, many gas furnaces serve fifteen to twenty years or longer. Poor airflow and skipped maintenance are the most common reasons furnaces fail early.
Related heating and airflow services
Ducts, controls and alternative heat sources all affect how well a new furnace performs.
Get a furnace sized for your home
Call to arrange a load calculation and duct inspection. Written options follow, with no pressure to decide on the spot.
Click Here To Call (888) 418-3681- Load-based sizing
- Venting and drain checked
- Temperature rise recorded
- Combustion analysis at startup