A gas furnace is the only appliance in most houses that burns fuel a few feet from the air you breathe, separated by a single steel wall. That is entirely safe when the wall is intact and properly vented, which is why every furnace we touch gets a heat exchanger inspection and combustion test whether or not that is what you called about.
Napps Heating — Longview & East Texas since 1957
The components that actually fail, in roughly the order we find them. Most are inexpensive; the important thing is diagnosing which one rather than replacing several.
Hot surface ignitors crack, and they crack during idle months rather than during use. It is the single most common no-heat cause we attend on the first cold night.
A thin rod that confirms the burner actually lit. It oxidises over time, stops sensing, and the furnace shuts the gas off a few seconds after lighting — as designed.
The steel barrier between combustion and your supply air. We inspect it on every visit, because a crack is a carbon monoxide problem rather than a comfort one.
Bearings dry out, capacitors weaken, and wheels collect enough dust to fall out of balance. Usually announced by noise well before failure.
Resistance heating elements and the sequencers that stage them. One failed element gives you a system that runs constantly and never quite gets there.
Pressure switches, limit switches and control boards. These are the expensive end, which is exactly why they should be diagnosed rather than assumed.
This is the part of furnace service that nobody enjoys discussing and everybody should understand.
Combustion happens inside the heat exchanger. Your house air passes over the outside of it, picking up heat but never mixing with the exhaust. A crack breaks that separation and allows combustion gases — including carbon monoxide — into the air distributed through your home. Carbon monoxide is colourless and odourless, so there is no warning from your senses. This is why a cracked exchanger means the furnace should not run, regardless of what a repair would cost.
Furnace Replacement →A properly burning gas flame is crisp blue, sometimes with a small blue-green centre. Yellow, orange or lazy flames indicate incomplete combustion, which is how carbon monoxide is produced. It can be caused by dirty burners, insufficient combustion air or a venting problem. It should never be dismissed as cosmetic — switch the system off and have it looked at.
Heating Maintenance →Headache, dizziness, nausea, weakness and confusion — often described as feeling like flu without a fever. The pattern that should raise concern is symptoms that improve when you leave the house and return when you come back, and several people or pets in the household affected at once. If you suspect it, get everyone outside into fresh air and call the gas utility before anyone else.
Indoor Air Quality →A visual inspection alone can miss a crack, particularly a hairline one on a section of exchanger that is hard to see. Combustion analysis measures what is actually coming out of the appliance, which is the only way to be confident about a system rather than hopeful. Every gas furnace we service gets both.
Heating Maintenance →What to do, and how urgently.
| What You Notice | What It May Mean | What To Do |
|---|---|---|
| Yellow or lazy burner flame | Incomplete combustion | Switch off and call |
| Flu-like symptoms that ease outdoors | Possible CO exposure | Leave, get air, call the gas utility |
| Soot or staining around the furnace | Combustion or venting problem | Switch off and call |
| Bang when the burner lights | Delayed ignition | Book a service promptly |
| Lights then stops after seconds | Flame sensor or limit | Book a service — not dangerous |
Or call 903-758-6482 — 24/7
The complaint gets fixed. The safety side gets checked either way.
What it does and when it was last looked at. Both narrow the likely cause considerably.
We follow the ignition and control sequence rather than replacing components hopefully.
Heat exchanger and combustion checked on every gas furnace, whatever you called about.
You approve a figure first, and we explain what failed and what it means for the system’s remaining life.
Some of these are inconvenience. Two of them are not.
Combustion safety treated as non-negotiable rather than an upsell.
Or call 903-758-6482 — available 24/7
These come straight from our Google Business Profile — unedited, and updated automatically as new reviews come in.
What Longview homeowners ask about gas and electric furnaces.
You often cannot tell from the outside, which is exactly why it matters. Warning signs include a yellow rather than blue flame, soot or staining near the unit, an unusual smell when running, and household members getting headaches or nausea that ease when they leave the house. Confirmation needs a physical inspection plus combustion analysis. If it is cracked, the furnace should not be run.
Often 15 to 20 years, which is at the longer end, simply because they run so few hours a season compared with a northern climate. The catch is that long dormancy causes its own wear — ignitors, sensors and motors deteriorate sitting still. So you get more calendar years but not necessarily fewer component failures along the way.
Almost always a dirty flame sensor. It is a thin metal rod whose only job is to confirm the burner actually lit; when it oxidises it stops sensing, and the control board shuts the gas off because as far as it knows there is gas flowing with no flame. That is the safety system working correctly. Cleaning or replacing the sensor is inexpensive and it is one of the most common calls we get.
A dusty burning smell on the first run is normal — nine months of settled dust burning off the heat exchanger — and it should clear within an hour. What is not normal is a smell that persists, anything acrid or electrical, or anything resembling gas or rotten eggs. Those mean shut it down and call.
Yes, in any home with gas appliances, and it is one of the cheapest pieces of safety equipment you can own. Place one near sleeping areas and test it periodically. It is a backstop rather than a substitute for annual furnace servicing, but it is a backstop worth having.
Yes. Electric furnaces have no combustion to worry about, so the safety picture is simpler, but they have their own failure pattern — heating elements burn out and sequencers stick, giving you a system that runs constantly and never quite reaches temperature. They also cost considerably more to run than a heat pump, which is worth discussing if yours is nearing replacement.
Repair, replacement and maintenance each have their own page with more detail.
Heat exchanger and combustion checked on every gas furnace we service — whatever you called about.
Tell us what the furnace is doing. If you smell gas, leave the building and call the gas utility from outside before contacting us.
