Furnace Replacement in Granbury, TX: When Repair Stops Making Sense

Furnace replacement in Granbury starts when a repair quote and the furnace in the attic no longer belong in the same sentence. The igniter failed last winter. The flame sensor failed the winter before. This year the cabinet is rusted, the flame is lazy and yellow, or the house could not hold temperature on a night in the 20s. Hood County winters are mostly mild. Then a front arrives, or a hard freeze shows up the way February 2021 did across North Texas, and a furnace that coasted on short runtimes has to work.

Granbury is the Hood County seat, on Lake Granbury, with in-town houses, lake-area homes, and acreage. Furnaces sit in closets and in attics. Some outlying lots heat with propane. This page is the decision: which failures are still a repair, what national guides say a replacement costs, and why the install matters more than the badge.

If you smell gas (a rotten egg odor), stop. Do not flip switches or use a phone inside. Leave the home and call your gas utility or 911 from outside. If a carbon monoxide alarm sounds, or anyone has a headache, nausea, or dizziness that eases outdoors, get everyone out and call 911. Do not shop for a furnace from inside the house. Do not open the burner cover, and do not adjust the gas valve.

Smoke, soot, or a breaker that will not stay on means the furnace stays off. A cracked heat exchanger is a safety problem. Leave that furnace off until it is checked.

What is still a repair

Do these before you decide the cabinet is finished. None of them open the burner box.

• Filter and vents. If you cannot see light through the filter, replace it. Open the supplies and uncover the returns. A limit trip from a packed filter can look like a dying furnace. If the burners stay on after a new filter, you did not need a new heat exchanger.
• Thermostat. Heat, fan AUTO, setpoint a few degrees above the room. Replace dim batteries. Emergency or Aux heat, on a heat pump, is not the same call as a gas furnace.
• One restart. After the filter change, restart once. If the burners light and hold, watch a full cycle. If they die again, a rollout has tripped, or the flame is yellow, stop.

An igniter, a flame sensor, or a capacitor on a younger furnace with a sound exchanger is usually a repair. You should hear that price before parts go in. The U.S. Department of Energy's Energy Saver guide lists a furnace more than 15 years old as one reason to consider replacement. It is a prompt, not an expiration date.

The failure list, written for Grand Prairie, is signs your furnace needs to be replaced in Grand Prairie. The national dollar bands, written for Fort Worth, are in furnace replacement cost in Fort Worth.

When replacement is the clearer conversation

The heat exchanger. Soot, a yellow lazy flame, rust flakes at the burner opening, or exhaust you can smell means leave the furnace off. A cracked heat exchanger is not a part you patch. The technician confirms it. You do not confirm it by removing the cover.

The metal around it. Heavy rust through the cabinet, a metal flue with holes, or a condensing furnace whose attic drain has failed more than once. A high-efficiency furnace makes water. A drain you cannot trust over a ceiling, or a PVC vent that has come apart, is a safety problem on an older unit.

Repairs that keep stacking. A heat exchanger, a failed blower, and a control board inside two winters is a different spend from one igniter. Ask for the repair total and a replacement total on the same visit.

It cannot keep the house warm after the airflow is fixed. A furnace that still cannot hold the setpoint on a night in the 30s, with a clean filter and open vents, is not doing its job. Find out whether the cause is ducts, the flue, or a furnace that short cycles because it is too large or starved of air. Do not buy a bigger input to fix short cycling.

Water at a ceiling, or ice on the outdoor unit, is a cooling repair. That visit is AC repair in Granbury.

What national guides say the job costs

For a gas furnace, Angi and HomeAdvisor put most installed replacements between about $3,800 and $10,000. Angi reported a national average around $7,000 for a house in the 1,600 to 2,000 square foot range. High-efficiency models are often quoted higher. Published figures for those sometimes reach about $12,000.

A wider Angi range that mixes every fuel type sits lower, roughly $2,800 to $6,900, with an average near $4,800. These are national industry ranges, not a Granbury price, and not a Boost Air quote. Your price depends on the system, the house, and the install.

A furnace-only replacement includes the furnace, labor, the vent connection, the fuel connection, electrical, thermostat setup, haul-away, and the permit. If the evaporator coil sits with the furnace, the quote should say whether that coil stays. Lines that move a Hood County total:

• 80% versus condensing. An 80% furnace uses a metal flue. A furnace around 90% AFUE or higher uses PVC vents and a condensate drain. In an attic, that drain can cost more than the difference in the box. Choose condensing when the vent and the drain are practical. Stay with 80% when the attic cannot take the water.
• Fuel. Many in-town houses are on natural gas. Some acreage lots use propane. The orifices and the regulator have to match. Name the fuel on the bid before you compare two totals.
• Ducts and size. The old BTU number is not a load calculation. A starved return trips the limit on the new furnace the same way it tripped the old one. HomeAdvisor cites about $1,000 to $2,700 for ductwork in its HVAC tables. Heavier trunk work costs more.
• The air conditioner. Leave a sound air conditioner in place and ask for the furnace-only price next to a full-system price.

The current federal minimum is 80% AFUE. A rule on the books would raise that to 95% for furnaces manufactured on or after December 18, 2028, and that date has been under review.

Why the install outlasts the name on the cabinet

Airflow, a flue that drafts, and a size that does not short cycle protect the heat exchanger. A premium furnace on a clogged return will have a shorter life than a plain furnace with those items done right. Commissioning means gas pressure, temperature rise, and a combustion check.

Furnace installation and replacement should name the vent material, the fuel, and how the BTU size was chosen. Labor coverage in writing, separate from the manufacturer parts coverage, belongs on the same quote. If a bid is far under the others, look for a missing flue, a missing permit, an assumed fuel, or a furnace that is simply too large.

Free replacement estimates

Talk with a knowledgeable North Texas comfort advisor about your replacement options. Free estimates, no pressure.

Boost Air And Plumbing installs gas and electric furnaces in Granbury, Fort Worth, Arlington, and nearby communities. We do not install boilers. See our furnace installation and replacement service. Call (817) 612-9107 or book online. Hours are Monday through Saturday, 8am to 7pm, with after-hours and Sunday emergency appointments available.

Frequently asked questions

When should a Granbury furnace be replaced instead of repaired? Age plus a major failure is the usual pair. A cracked heat exchanger, a rusted cabinet, or a second expensive repair on a furnace around 15 years old is a replacement conversation. A failed igniter, flame sensor, or capacitor on a younger furnace that still heats the house is usually a repair. Get both prices after someone has seen the furnace. A gas smell or a carbon monoxide alarm means leave the house first.

How much does furnace replacement cost in Granbury? National guides updated for 2026, including Angi and HomeAdvisor, put most gas furnace replacements between about $3,800 and $10,000 installed. Angi reported a national average around $7,000 for a mid-size house, and high-efficiency models are often quoted higher, sometimes toward $12,000. A separate Angi range that mixes all fuel types sits lower, roughly $2,800 to $6,900. These are national industry ranges, not a Granbury price and not a Boost Air quote. Your price depends on the system, the house, and the install.

Does the brand decide whether the next furnace lasts? No. Sizing, airflow, venting, and the refrigerant-side coil match matter more than the name on the cabinet. A correctly sized furnace with open returns and a flue that drafts will outlast a premium furnace that was oversized and starved of air. Ask how the BTU size was chosen, and ask for a free replacement estimate that names the vent and the fuel.

Do acreage homes around Granbury use the same furnace as in-town houses? Many in-town houses are on natural gas. Some acreage lots use propane because a gas main never reached the property. The furnace, the orifices, and the regulator have to match that fuel. A quote should name propane or natural gas before you compare the totals. The national cost bands are still industry ranges, not a Hood County price.