Gas Furnace Repair in Houston, TX - Combustion Experts

75 Degree AC diagnoses and repairs gas furnaces across Houston TX, including ignition failures, burner problems, heat exchanger concerns, gas valve faults, and draft inducer issues. Our licensed technicians understand gas combustion systems inside and out, and every repair includes a full safety check before we leave.

75 Degree AC gas furnace specialists serving residential and commercial heating systems in Houston TX

Houston Gas Furnace Specialists for Residential & Commercial Heating Systems

75 Degree AC works on gas furnace repair calls throughout Houston every week. Our specialists diagnose and fix problems in the ignition system, burner assembly, heat exchanger, gas valve, draft inducer, and every other component in the combustion chain. That focused experience with gas furnace repair means we find what failed and why, not just what part to swap.

Every gas furnace repair starts with a combustion analysis and gas pressure test before any parts are replaced. The full price is given upfront and does not change after the work begins. When a gas valve or igniter can be replaced to restore safe operation, we complete the repair and test the system. When a cracked heat exchanger or repeated failures make replacement the better choice, we explain the situation honestly so the homeowner can decide.

Our gas furnace repair service in Houston is backed by fully licensed and insured contractors. We carry common gas furnace parts like igniters, flame sensors, gas valves, and pressure switches on every truck. Same-day availability keeps the wait short, especially when the home has no heat.

Gas Furnace Failures Our Professionals Repair in Houston

Furnace Ignition Failure

When the gas furnace clicks but the burner never lights, the problem usually sits with the hot surface igniter, the flame sensor, or the gas valve itself. Our contractors test igniter resistance, sensor microamp output, and gas valve voltage to isolate the failure before replacing any parts.

Weak Burner Flame

A burner that lights but produces a low, uneven, or yellow flame is not getting the correct air-to-gas ratio. Dirty burner ports, incorrect gas pressure, or a clogged orifice are the most common causes. We clean the burner assembly, test manifold pressure, and adjust until the flame burns steady and blue.

Heat Exchanger Crack

A cracked heat exchanger can allow combustion gases, including carbon monoxide, into the home's air supply. Our team performs a visual inspection and a combustion analysis to detect cracks or corrosion. When a heat exchanger is compromised, we explain the safety concern and present the repair and replacement options clearly.

Gas Valve Failure

The gas valve controls fuel flow to the burner. When it sticks open, fails to open, or leaks, the furnace either will not light or becomes a safety concern. Our specialists test valve operation with voltage checks and gas pressure readings to confirm the failure before replacing the valve.

Draft Inducer Issues

The draft inducer motor creates the airflow needed to pull combustion gases through the heat exchanger and out the flue. When it fails or slows down, the pressure switch will not close and the ignition cycle never starts. We test motor operation, pressure switch activation, and flue clearance to find the cause.

What Customers Say About Our Service

Why 75 Degree AC Is the Right Team for Gas Furnace Repair

When you need gas furnace repair in Houston, 75 Degree AC brings combustion expertise to every call.

Combustion System Experts

Our contractors work on gas combustion systems every day. Burner assemblies, heat exchangers, gas valves, and flue systems are checked and tested on every call. That daily experience means faster, safer diagnosis.

Gas Safety Priority

Every gas furnace repair includes a combustion analysis, gas pressure test, and carbon monoxide check before we leave. Safety is built into the process, not treated as an add-on.

Price Set Before Work

The full repair cost is given before any work starts. There are no surprise charges, no diagnostic fees rolled into the final bill, and no price changes once the job begins.

Every Gas Furnace Brand

We repair gas furnaces from all major brands found in Houston homes. Both condensing and non-condensing systems are serviced, with repairs completed based on the type and condition of the unit.

Get Your Gas Furnace Repaired Without Delay

Ready to get your gas furnace fixed? Call (713) 598-2737 to book with 75 Degree AC. Upfront pricing, no hidden fees, and same-day scheduling across Houston.

How Our Gas Furnace Repair Process Works

75 Degree AC follows the same structured process on every gas furnace repair call in Houston, from the first phone call to the final safety check.

75 Degree AC gas furnace repair process in Houston TX

Report the Failure

Call us or book online and describe what the gas furnace is doing. When the burner will not light, the flame looks wrong, or the system shuts down mid-cycle, that detail helps our technicians bring the right parts.

Test Combustion System

Our contractors test the igniter, flame sensor, gas valve, burner assembly, and draft inducer. Gas pressure at the manifold is measured. Combustion analysis confirms the system is burning fuel safely and completely.

Explain and Quote

The cause of the failure is explained in plain terms. The full repair price is given before any work starts. No work begins without the homeowner agreeing to the cost.

Replace Failed Parts

The failed component is replaced with a part matched to the gas furnace. Gas connections are sealed, electrical terminals are secured, and the burner is tested for proper flame pattern before proceeding.

Verify Safe Operation

The furnace runs through a full heating cycle under load. Gas pressure, temperature rise, flue draft, and carbon monoxide levels are all checked. The system is confirmed safe and heating properly before the contractor leaves.

Our Recent Projects in Houston

Business Hours

Monday 7 AM–9 PM
Tuesday 7 AM–9 PM
Wednesday 7 AM–9 PM
Thursday 7 AM–9 PM
Friday 7 AM–9 PM
Saturday 8 AM–8 PM
Sunday 8 AM–5 PM
75 Degree AC gas combustion cycle process inside furnace in Houston TX

How the Gas Combustion Cycle Works Inside Your Furnace

A gas furnace starts each heating cycle when the thermostat calls for heat. The draft inducer motor activates first, creating airflow through the heat exchanger and flue pipe. Once the pressure switch confirms proper draft, the igniter heats up and the gas valve opens to deliver fuel to the burner assembly. The flame sensor then confirms that the burner is lit. Combustion gases pass through the heat exchanger, which transfers heat to the air being pushed through the duct system by the blower motor. 

In a condensing gas furnace, a secondary heat exchanger captures additional heat from the exhaust before it exits, which is why condensing units have higher AFUE ratings and produce condensate that drains through a separate line. Every component in the combustion chain, from the draft inducer to the flue pipe, must work in sequence.

Proudly Serving the Entire City of Houston TX

75 Degree AC provides HVAC services across Houston TX, supporting residential and light commercial properties throughout the city. Our service coverage reflects how HVAC demand actually works in Houston, from central neighborhoods to outer city districts. Customers rely on us for consistent service standards, clear communication, and dependable system support city-wide.

Schedule Gas Furnace Repair in Houston Today

When your gas furnace is not lighting or running safely, waiting is not worth the risk. Reach 75 Degree AC at (713) 598-2737 for same-day gas furnace repair in Houston. Our contractors bring the parts, diagnose the combustion system, and get your heat running before the day is over.

About Houston, TX

Natural gas is the primary fuel source for residential heating in most Houston, TX neighborhoods. Homes in the Third Ward, East End, and Northside have some of the oldest gas furnaces in the metro, with burner assemblies and heat exchangers that have been exposed to Houston’s humid air for years. Corrosion builds up on internal components even during the months when the furnace sits idle, and the first cold front of the season is often when a corroded gas valve or cracked heat exchanger makes itself known.

In Denver Harbor, Magnolia Park, and the neighborhoods east of downtown, many homes rely on gas furnaces as their only heat source. A gas furnace failure during a cold snap leaves these homes without heat and creates a safety concern when homeowners turn to space heaters or leave the oven running. Having a licensed contractor diagnose and repair the gas furnace quickly and safely is the best way to get the home warm without introducing new risks.

Frequently Asked Questions FAQ's

A brief gas smell on startup can happen when residual gas in the combustion chamber ignites. A persistent or strong gas smell means there may be a leak at the gas valve, manifold, or supply line. Turn the furnace off and call a licensed contractor immediately for a safety inspection.

A yellow flame means the burner is not getting the right air-to-gas mixture, which can produce carbon monoxide. The most common causes are dirty burner ports, a clogged orifice, or incorrect gas pressure. Our contractors clean and adjust the burner to restore a steady blue flame.

In most cases, a cracked heat exchanger cannot be patched safely. The crack allows combustion gases into the home’s air supply, which is a serious safety concern. Our contractors present both the heat exchanger replacement cost and the full furnace replacement cost so the homeowner can make the right decision.

The most common causes are a dirty flame sensor that cannot detect the burner flame, a failing limit switch that trips from overheating, or a clogged air filter that restricts airflow. Our contractors test all three components to find the exact cause of the shutdown cycle.

Delayed ignition happens when gas builds up in the combustion chamber before the igniter lights it, causing a loud bang on startup. It can damage the heat exchanger over time and is a safety concern. Our contractors clean the burner assembly and check igniter timing to correct the issue.

Yes. Every gas furnace repair includes a combustion analysis to measure flue gas temperature, carbon monoxide levels, and combustion efficiency. This confirms the furnace is burning fuel safely and completely before we close out the job.