Finger pressing a wall thermostat in warm lamp light on a cool evening

Furnace Repair in Houston, TX

A Houston gas furnace can sit untouched for most of the year, then get asked to run all night when the first real cold front rolls in. One free call, any hour, puts you through to an independent, locally owned heating company in the Houston area.

Call (832) 662-4107 Match your furnace symptom

Furnace repair in Houston has its own rhythm. Heating season here is short, so a gas furnace tucked into an attic, hall closet or garage may go eight or nine months without lighting once. When a norther finally pushes through and the thermostat calls for heat, the parts that dried out, collected dust or quietly failed over the summer all get tested in the same night. This page puts gas and carbon monoxide safety first, then walks through how a furnace starts, what common symptoms tend to mean and what to ask the company that comes out.

Houston Air & Heating does not fix furnaces; it runs a free phone number. Dial (832) 662-4107, day or night, and an automated assistant picks up, checks that you need help with heating or cooling, and notes what the furnace is doing. It then hands the call to a locally owned HVAC business working in the Houston area, independent of the line. That company inspects the furnace, quotes the repair, does the work and bills you directly.

Gas and carbon monoxide safety before any furnace repair

Natural gas burns inside the furnace, often just down the hall from the bedrooms. These two situations come before the cold, the repair and the bill.

You smell gas

CenterPoint Energy, the gas utility for most Houston homes, says to leave on foot immediately. Skip the light switches, phones, car and anything else that might spark, and leave the meter and valves alone. From a safe distance, call 911 and CenterPoint's gas leak hotline at 888-876-5786. Do not assume a neighbor already called it in.

The CO alarm goes off, or people feel sick

Carbon monoxide is a poison gas you cannot see or smell. According to the CDC, poisoning often starts with a headache, dizziness or weakness and can bring nausea, vomiting, chest pain or confusion; someone asleep can be overcome before waking. Move every person and pet outdoors, then dial 911.

Keep CO alarms working. Put them outside sleeping areas and on each floor, and test them when you test your smoke alarms.
Leave the burner area to a technician. Do not relight burners, jump a safety switch or take the burner door apart.
Keep fuel-burning equipment out of the house. No generators, grills or camp heaters indoors or in an attached garage, even with the door up.

Where Houston gas furnaces live, and why that matters

In many Houston homes the furnace is not in a basement. It sits on a platform in a hot attic, stacked under the air handler and coil that cool the house all summer, or it lives in a hall closet or garage. That location shapes repairs. Attic units bake through months of Gulf Coast heat while they wait, the filter and blower get a full cooling season of use, and wasps, rodents and dust find their way into burner compartments and vent pipes.

Across Texas, gas is actually the minority heat source. Citing Census figures, the U.S. Energy Information Administration put electricity as the main heating fuel in 61 percent of Texas homes, against roughly 35 percent for natural gas. If your system has no gas line, burners or flue pipe, it is likely a heat pump or electric strip heat, and our heating repair page for heat pumps and electric heat fits your situation better.

Air handler in a Houston-style attic with flexible ducts and pink insulation around it

A gas furnace still depends on electricity. EIA points out that most modern gas furnaces need power to ignite and to run the fan that moves warm air through the ducts. So when the lights go out in a storm, the furnace goes quiet too, even with gas at the meter.

How a gas furnace starts, step by step

Most furnace problems are a break somewhere in a fixed start-up chain. Knowing the order helps you tell the assistant, and then the technician, exactly where your furnace stops. Typical modern furnaces follow a sequence like this:

The thermostat calls for heat. A low-voltage signal tells the control board to begin.
The inducer motor starts. This small fan pulls air through the burner area and pushes exhaust up the vent before any gas flows.
The pressure switch proves the draft. If the vent is blocked or the inducer is weak, the switch stays open and the furnace stops here.
The igniter heats up. On most newer furnaces a hot surface igniter glows bright orange. Older units may use a spark or a standing pilot.
The gas valve opens and the burners light. Flame rolls across the burners within a few seconds.
The flame sensor confirms the flame. If it cannot detect flame, the board closes the gas valve almost immediately. This is why a dirty sensor causes the "lights, then quits" pattern.
The blower comes on. After the heat exchanger warms up, the main fan starts pushing warm air to the rooms.
The limit switch keeps watch. If the furnace runs too hot, often because of a clogged filter or closed vents, the limit switch shuts the burners off.

Gas furnace with the front panel removed and a flashlight shining on the burner compartment — The igniter, burners and flame sensor sit behind the furnace door. Testing and cleaning them is a job for a trained technician.

Houston furnace symptoms and what they often point to

Read across a row to put words to what you see before you phone. Nothing here is a repair manual, and the right-hand column belongs to the technician alone.

Gas furnace symptoms, likely causes, safe homeowner checks and what a technician tests
What you notice	Common causes	Safe for you to check	What the technician tests
Nothing happens at all	Thermostat setting or dead batteries, a tripped breaker, the furnace switch turned off, a blown low-voltage fuse or failed board	Thermostat on Heat and set above room temperature, fresh batteries, reset the breaker once, the light-style switch near the furnace turned on	Power at the furnace, the thermostat signal, the transformer, fuse and control board
Inducer hums, but no glow and no flame	Pressure switch not closing, blocked vent or condensate line, cracked igniter	That the furnace door is seated, since a door switch can keep it off	Pressure switch and hoses, vent and drain, igniter resistance, any error code blinks
Burners light, then shut off within seconds	Dirty or worn flame sensor, weak ground, gas pressure problem	Nothing beyond the filter; do not open the burner area	Flame signal reading, sensor condition, gas pressure, grounding
Runs a while, shuts off, then starts again	Limit switch tripping from overheating, often from poor airflow	The air filter, and that supply and return vents are open and clear	Temperature rise across the furnace, blower speed, duct restrictions, limit switch
Blower runs but the air is cool	Burners not lighting, fan set to On instead of Auto, or a heat pump system instead of gas	Thermostat fan setting on Auto	The full start-up sequence above, gas supply to the furnace
Dusty smell on the first cold night	Dust burning off after months idle	Change the filter and let it run; it should fade	Only needed if it lasts or grows stronger
Loud bang at ignition, soot or a yellow, lazy flame	Delayed ignition, dirty burners, combustion or venting trouble	Turn the system off at the thermostat and call; keep CO alarms on	Burners, gas pressure, combustion, heat exchanger and flue

If you smell gas at any point while checking, stop and follow the safety steps near the top of this page. Furnace safety controls exist to keep gas from burning when conditions are unsafe, so never bypass one to get heat back.

What the February 2021 freeze taught Houston about furnace repair

Houston homeowners do not need furnaces often, but when they do, they really do. During the Valentine's week storm of 2021, Bush Intercontinental Airport dropped to 13 degrees on the morning of February 16, and the National Weather Service office for Houston and Galveston issued its first ever wind chill warning. NWS records show the City of Houston struggled to a high of only 25 degrees on February 15.

The grid failed at the same time. A University of Houston Hobby School report put the peak at close to 4.5 million Texas homes and businesses without power. A gas furnace with gas at the meter but no electricity cannot run its igniter or blower, so many Houston families with gas heat were cold anyway. Some tried to warm up with cars, grills or generators too close to the house, and the Texas Department of State Health Services later counted 19 storm deaths from carbon monoxide poisoning, from generators, grills, heaters and vehicles used in enclosed spaces and from ice blocking the vents of gas heating equipment.

Plan for an outage, not just a cold night. Extra blankets and a safe warm room beat any improvised heat source.
Generators go outdoors only, well away from windows, doors and vents, never in the garage.
After the power returns, watch the first few heat cycles. If the furnace will not light, short-cycles or smells wrong, call instead of resetting it repeatedly.

Fall checks before the first Houston cold front

A few minutes in October can save a cold call in December. These are safe for any homeowner:

Switch the thermostat to Heat on a cool afternoon and raise it a few degrees to confirm the furnace lights and warm air arrives.
Put in a fresh filter. ENERGY STAR suggests checking it every month; a summer of cooling leaves many Houston filters clogged.
Test the carbon monoxide alarms and replace batteries.
Clear the space around the furnace. Closet and garage furnaces need breathing room; boxes, paint cans and cleaning products do not belong there.
Look, do not touch, at the vent pipe where you can see it. A loose, rusted or disconnected flue is a reason to call.

For the inside of the furnace, ENERGY STAR advises a yearly checkup by a contractor covering gas connections, gas pressure, burner combustion and the heat exchanger, plus a check that the system starts, runs and shuts off properly. Our HVAC tune-up page explains what a full visit should include.

What a careful technician does on a furnace call

A good diagnosis follows the furnace through its start-up sequence and finds the exact step where it fails. On a no-heat call you can expect a technician to read any blinking error code on the control board, watch the inducer, pressure switch, igniter and flame sensor in order, measure gas pressure, and check temperature rise and airflow so the limit switch is not tripping. Because a furnace burns fuel inside the home, a thorough technician also looks at the flue, the burners and the heat exchanger, and tests for carbon monoxide around the appliance.

Technician reading service gauges at an outdoor unit beside a brick home with a wood fence

Questions worth asking the company you are put through to

What is the diagnostic or service call fee, and does it count toward the repair?
What exactly failed, and what test showed that?
Will I get a written price before the work starts?
Is the heat exchanger and venting in safe condition?
If replacement comes up: will you pull the City of Houston permit? Inside city limits, the "Replace Heater Only" mechanical permit must be obtained by a contractor licensed by TDLR and registered with the city, and the work is inspected.
What is your Texas ACR license number?

Still no heat after checking the thermostat, filter and breaker? Call any hour and tell the assistant you have a gas furnace, where in the Houston area you are and what it is doing.

Call (832) 662-4107

Furnace repair in Houston through the free line

Calling the line costs nothing. You explain the problem once, and the company you reach already has a short summary when it picks up. If nobody can answer right then, your name, callback number, area and problem are passed along so the company can call you back. Pricing, scheduling and the repair itself are between you and that company.

Dial the numberAn automated assistant picks up (832) 662-4107 at any hour and asks what you need help with.
Say what is wrongTell it whether the trouble is cooling or heating, where in the Houston area you are, and what the system is doing.
Reach a local companyYour call is transferred to an independent, locally owned HVAC company, which gets a short summary of your problem before it answers.
Work it out with themThat company inspects, quotes, repairs and bills you directly. If nobody can pick up, your name, number and problem are passed on for a call back.

About this line: Houston Air & Heating is a free phone line, not an HVAC contractor. It answers your call and connects you with an independent local heating and air conditioning company, which inspects, quotes and does the work, and which you pay directly. Companies may pay a referral fee. You never pay the line. Read how the line works.

Verify the license before work begins. Texas requires anyone contracting to do air conditioning, refrigeration or heating work to hold an Air Conditioning and Refrigeration (ACR) Contractor license from the Texas Department of Licensing and Regulation (TDLR). Ask the company for its ACR license number, then confirm it on the TDLR license search (opens in a new tab). The line does not check this for you.

Related services and guides

Furnace help across greater Houston

The line takes heating calls from Houston and its suburbs in Harris, Fort Bend, Montgomery, Brazoria and Galveston counties.

Common questions

I smell gas by the furnace in my Houston home. What now?

Get everyone out of the house on foot right away. Do not flip light switches, use a phone, start a car or do anything else that could make a spark on the way out, and do not touch the gas meter or any valve. Once you are a safe distance away, call 911 and CenterPoint Energy's gas leak hotline at 888-876-5786. Stay out until the gas company or fire department says the home is safe.

Why does my furnace light and then shut off a few seconds later?

That pattern usually means a safety control stopped the burners because it did not confirm what it needed. A flame sensor coated with grime is a frequent reason. A clogged filter that lets the furnace overheat, a blocked vent or a weak pressure switch can cause the same thing. A technician should test each step instead of resetting the furnace over and over.

Is a burning smell normal the first time I turn the heat on?

A dusty, toasty smell for a short while on the first cold day is common, because dust settles on the heat exchanger during the months the furnace sits idle. It should fade within the first hour or so. A smell like hot plastic, melting wire or rotten eggs is different: shut the system off at the thermostat, and if it smells like gas, get outside first, then phone 911 and CenterPoint Energy.

How often does a furnace need maintenance?

ENERGY STAR recommends a heating checkup once a year, ideally in the fall before heating contractors get busy. On a gas furnace that check covers the gas connections, gas pressure, burner combustion and the heat exchanger. Between visits, look at the air filter every month and change it when it is dirty.

Will my gas furnace work if the power goes out?

Usually not. The U.S. Energy Information Administration notes that most modern gas furnaces need electricity to light and to run the blower that moves warm air through the house. Never try to heat the home with a gas oven or run a generator indoors or in the garage, because both can fill the house with carbon monoxide.

Furnace not heating? Call the free line

One free call, any hour. Say whether it is the AC or the heat, where you are and what is happening, and the line transfers you to an independent, locally owned HVAC company that looks at the system and prices the job itself.

Call (832) 662-4107

Any hourAn automated assistant takes calls around the clock, including weekends and holidays.
No charge to youThe line never bills callers. Prices come only from the HVAC company.
Ask for the ACR licenseGet the company's Texas license number and check it on TDLR before work begins.
Your decisionYou hear the diagnosis and the price first, then choose whether to go ahead.