Top-rated independent heating and cooling across North Texas and the Metroplex
CO Alarm Sounding
Your carbon monoxide alarm is going off and you need to know what to do right now. Get everyone out of the house, then call 911 or your gas utility from outside. Do not stop to hunt for the cause. Once the fire department or the utility has cleared the house, call us and we will inspect the heating system that set it off.
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By the Trinity Air & Heat service team · reviewed by our working technicians
The First Five Minutes, In Order
Do these in order and do not skip ahead. 1. Get every person and pet outside into fresh air. Leave the door open behind you if you can do it without slowing down. 2. Do not go back in for phones, chargers or paperwork. 3. From outside, call 911 or your gas utility's emergency line. Both will come out and both will take the call seriously. 4. Stay outside, away from the house, until they tell you it is safe to go back in. 5. If anyone has a headache, nausea, dizziness, confusion or blurred vision, tell the dispatcher. Those are symptoms of carbon monoxide exposure and they need medical attention, not fresh air alone.
What Not To Do
Do not open every window and then go back to bed. Venting the house can drop the reading enough to silence the alarm while the source keeps producing gas. Do not pull the battery out to stop the noise. Do not light a match, flip switches or use anything that sparks if you also smell gas, because a gas leak and a carbon monoxide problem can happen together. Do not try to open up the furnace, water heater or any gas connection yourself. Do not run the heat again to see if the alarm goes off a second time. Carbon monoxide has no smell and no color, so your nose is not a test.
Why A Heating System Sets It Off
Carbon monoxide comes from combustion that is not venting the way it should. On the calls we run across Texas, Oklahoma and Louisiana, the usual sources are a cracked heat exchanger in a gas furnace, a flue or vent pipe that has separated or rusted through, a blocked vent terminal, or a water heater backdrafting into the house because the space is starved for air. Attic installations hide a lot of this, since nobody sees the flue joint above the ceiling. A gas range, a running vehicle in an attached garage or a generator too close to the house can do it too. The alarm cannot tell you which one. An inspection can.
When To Call Us
Call us after the fire department or the gas utility has been out, not instead of them. They make the house safe. We find out what failed and fix it. When we arrive we test combustion, check the heat exchanger, follow the flue from the equipment to the roof or sidewall, and confirm the system has the return and combustion air it needs. If the heat exchanger is cracked, that furnace does not go back into service. We will tell you plainly whether the repair is a vent correction or a replacement, and we will not turn gas heat back on until it tests clean.
Keeping It From Happening Again
Put a carbon monoxide alarm on every level of the house and outside each sleeping area, and replace the alarms themselves when they hit their expiration date printed on the back. Most units quit sensing accurately after seven to ten years even though they still chirp. Test them monthly with the button. Have gas heating equipment inspected before the first cold snap, since that is when a summer's worth of rust and rodent damage in the flue shows up. Keep the area around the furnace clear so it can breathe, never store paint or solvents against it, and never run a generator or a grill in a garage, breezeway or carport.
Safe Checks You Can Do Yourself
There is a short list of things a homeowner can safely handle, and none of them involve gas, refrigerant or high voltage. You can change the air filter on schedule, since a starved blower makes everything work harder. You can check that the thermostat has fresh batteries and is set the way you expect. You can look at the breaker panel for a tripped breaker. You can walk the house and confirm supply and return vents are open and not blocked by furniture or rugs. You can clear leaves and grass clippings away from the outdoor unit. Anything past that, including anything that involves opening the furnace, is our job.
When it is time to book
CO Alarm Sounding — common questions
My alarm went off once and then stopped. Do I still need to call someone?
Yes. A single alarm event means carbon monoxide reached a level high enough to trip the sensor. Call the gas utility or 911 to check the house, then have us inspect the heating equipment and venting to find the source.
Can my AC cause carbon monoxide?
No. Electric cooling does not burn fuel, so it produces no carbon monoxide. The risk comes from gas or oil fired equipment such as a furnace, water heater or range, and from vehicles or generators near the house.
How do I know if it is a real alarm or a dead sensor?
You cannot tell from outside the house, so treat every alarm as real. Get out, call 911 or the gas utility, and let them measure the air. If the sensor is simply expired, we can confirm that afterward.
How it works
- Step 1
Tell us the symptom
Call or fill in the quote form with what you hear, smell or feel. Warm air, short cycling, a breaker that keeps tripping. Details on your porch help us arrive with the right parts.
- Step 2
We diagnose on site
A technician checks the thermostat, airflow, the indoor coil and blower, then the outdoor unit and electrical side. You get a plain explanation of what failed and why it failed.
- Step 3
You approve the repair
We walk you through the fix and any parts involved before we start. Once you say go, we make the repair and confirm the system is holding temperature before we leave your driveway.
- A real person answers
- Open 7 days
- Written quote before work starts
Why homeowners call us
- Built for hard summersWe work on attic air handlers in July heat, undersized returns in older subdivisions, and condensers with hail-flattened fins. Those are everyday jobs across the region, so we know where these systems tend to give out first.
- Air conditioner repair and heating repairOne crew for both seasons. Air conditioning repair when the house won't cool, heater repair and furnace repair when the burners won't stay lit. Same technicians, same records, so nobody starts from scratch in November.
- We explain the failureYou hear which component failed and what it was doing to the rest of the system. If a repair is a short-term patch on an aging unit, we say so and let you decide the timing.
- Respect for the houseDrop cloths, shoe covers, and the attic hatch closed the way we found it. We keep the work area clean and we tell you honestly when a problem is airflow or ductwork rather than the equipment itself.
- All major brands, gas & electricOne independent crew for Carrier, Trane, Lennox, Goodman, Rheem and more.
- Straight answersIf a system is not worth repairing, we say so, often right on the phone.
About this guide
If the safe checks didn't fix it, the fault is real
Mention which checks you ran when you book; it speeds up the visit.
- A real person answers
- Open 7 days
- Written quotes
- All major brands
- Gas & electric
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