A heater that won’t turn on at all — no click, no hum, no air — usually shows up on the same night every year in El Paso: the first one that is actually cold. The heater just sat unused for eight months, and the things that stop it are mostly small and safe to check yourself. Work through these in order before anyone comes out, and stop at the first sign of gas.
The five safe checks, in order
None of these require opening the burner area or touching anything that carries gas.
- Check the thermostat. After a summer on COOL, it is easy to miss that it never got switched back. Set it to HEAT and a few degrees above the current room temperature. If the screen is dim or blank, replace the batteries. Then give it about five minutes — many thermostats and heaters have a short built-in delay before starting.
- Check the heater’s power switch. Most heaters have their own on/off switch that looks exactly like a light switch, mounted on or near the unit — in a hall closet, the garage or the attic access. It gets flipped off by accident, or on purpose for the summer. Make sure it is ON.
- Check the breaker. Look in the electrical panel for a heater or furnace breaker that has tripped. Flip it fully OFF, then back ON — one time. If it trips again, stop and call; that is an electrical fault, not a fluke.
- Check the filter. The heater and the AC share one filter, and by fall it has eaten a full summer of dust. A badly clogged filter can make the heater overheat and shut itself down on a safety limit. If it is gray, replace it. Our guide to how often to change the filter in El Paso explains why the box’s 90 days rarely holds up here.
- Check the front panel. Heaters have a safety switch that keeps them off when the front door of the cabinet is not fully seated — common after someone changed the filter or peeked inside. Make sure the panel is closed all the way. Do not remove it to look inside.
One more check that takes ten seconds: does the rest of the house have gas? If the stove burners light and the water heater is making hot water, your gas service is fine. If nothing in the house gets gas, the problem is the supply, not the heater — call the gas company.
Quick diagnostic: what the heater is telling you
| What you notice | Most likely cause | What to do |
|---|---|---|
| Nothing at all — no sound, no air | Thermostat off or dead, power switch off, tripped breaker | Thermostat on HEAT, fresh batteries, power switch ON, breaker reset once |
| Blower runs but the air never warms | Ignition failure, or thermostat fan set to ON | Set the fan to AUTO; if it still blows cold, see our heater blowing cold air guide |
| Clicks or hums, tries to start, never lights | Worn igniter, pressure switch or control fault | Power switch off one minute and back on, once; if it fails again, call |
| Lights, runs a few seconds, then shuts off | Dust-coated flame sensor | Service call — cleaning it takes a technician minutes |
| Runs several minutes, burners go out, blower keeps running | Clogged filter tripping the high-limit switch | Change the filter; a repeat means a service call |
| Breaker trips again right after reset | Electrical fault in a motor, board or wiring | Leave it off and call |
| Rotten-egg smell, or a CO alarm sounds | Possible gas leak or combustion problem | Leave the house now; call 911 or the gas company from outside |
When it tries to start but won’t light
If you hear the heater click, hum or start its small fan but the burners never light, it has power and the thermostat is calling for heat — the ignition sequence is the part failing. Before and during lighting, its control board checks a chain of safety devices: that the exhaust vent is drafting, that the burners actually lit, that nothing is overheating. Any weak link in that chain — a cracked or worn igniter, a pressure switch that will not close, a flame sensor filmed with idle-season dust that cannot see the flame — and the board shuts the attempt down.
Many heaters try a few times and then lock out for a while. Turning the power switch off for a minute and back on resets that lockout once. If it fails again, that is your answer: it needs a technician. Many newer heaters also flash a code on a small light inside the cabinet, often visible through a little window in the front panel — if you can see it without removing the panel, count the blinks and tell us when you call. It speeds up the diagnosis.
What not to do: do not open the burner compartment, do not try to relight anything, and do not touch the gas valve or the wiring inside the unit. On gas equipment, the safety devices are doing their job when they keep the heater off.
Heat pumps: check the outdoor unit too
If your home heats with a heat pump instead of a gas heater, it usually runs on two circuits — one for the indoor unit and one for the outdoor unit — so check both breakers, and look for the outdoor unit’s disconnect box on the wall nearby. A heat pump that is fully dead after a cold night, or one covered in ice that never clears, is a service call. Our heating service covers gas heaters, electric heaters and heat pumps.
The El Paso pattern: why it fails on the first cold night
Our heating season is short and arrives fast. National Weather Service records for El Paso show the same pattern every year: the first real cold front arrives fast, and the whole valley turns its heat on within a day or two. The heater that sat untouched since March gets its first real job that night, with a dust-loaded filter, a dusty flame sensor and a thermostat still set for summer. That is why the repair schedule fills the same day the cold arrives.
The cheapest fix is the one done in October: a pre-season maintenance visit cleans the flame sensor, tests the igniter and safety switches, and checks the heat exchanger before you need heat. ENERGY STAR’s maintenance checklist recommends the same pre-season tune-up rhythm, and the U.S. Fire Administration recommends having heating equipment inspected by a professional every year.
Stay warm safely while you wait
A dead heater on a cold night is when people improvise — and some improvisations are dangerous.
- Never heat the house with the kitchen oven, a grill or a generator indoors. They can fill the home with carbon monoxide, which you cannot see or smell.
- Keep space heaters at least three feet from anything that can burn — curtains, bedding, furniture — and turn them off when you leave the room or go to bed. Those are the U.S. Fire Administration’s recommendations, not just ours.
- Have working carbon monoxide alarms on every level of the home, outside the sleeping areas, as the Consumer Product Safety Commission recommends.
Two situations that are not DIY
If you smell gas — the rotten-egg odor — do not flip switches, do not try to start the heater, and do not look for the leak. Leave the house and call 911 or the gas company from outside. If a carbon monoxide alarm sounds, get everyone out first, then call.
For everything else on this page, we schedule heating repair calls same-day whenever we can, Monday through Friday from 7am to 5pm, from our shop at 6928 Doniphan Dr in Canutillo — (915) 877-2284. Every heating service call includes a heat-exchanger safety inspection, and you get the repair price before we start. Family-owned since 1992, licensed in Texas (TACLA00118528E) and New Mexico (#359536).