Modern Furnaces, Diagnosed Right
Los Angeles heating systems don’t get the workout that cooling systems do. Most furnaces run for a few months, then sit idle until the next cold stretch. That means heating problems often go unnoticed until the system is finally needed again.
Heating systems usually give you a warning before they quit — the trick is knowing what they’re telling you.
Most heating problems don’t start with a complete breakdown. The signs usually show up first — the system may not heat properly, shut off unexpectedly, or fail to respond at all. What causes those symptoms depends in part on the type of heating system. Gas furnaces and heat pumps work differently, so we look at different things when figuring out what’s wrong.
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Gas furnace problems often involve ignition components, restricted airflow, or safety controls. A furnace may fail to start, blow cold air, or fire and then shut off when a safety control detects a problem.
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Heat pump problems often involve the refrigeration system, defrost cycle, controls, or electrical components. A heat pump may run without warming the house, get stuck in defrost mode, or blow air that never really heats up.
Heating systems in Los Angeles run fewer hours per year than systems in colder climates. That sounds like an advantage—and for equipment wear, it mostly is. But it also creates a different problem: issues that would show up quickly under heavy use go unnoticed because the system doesn’t run long enough to reveal them.
A gas valve that’s starting to stick. An igniter that’s weakening. A heat exchanger developing a crack. Problems like these usually don’t show themselves until the system is asked to perform — which in Los Angeles often means the first cold stretch of the year, when you can least afford to be without heat.
Because heating systems sit idle for much of the year in Los Angeles, a preseason inspection can catch worn ignition components, airflow restrictions, venting issues, and other developing problems before the heating season begins.
Even with a preseason inspection, things can still go wrong. When they do, proper diagnostics matter. We look beyond the symptom to find what’s causing it.
Modern furnaces are built with safety systems that shut things down when something isn’t working properly.
A furnace that won’t start, keeps shutting off, or blows cold air is usually reacting to another problem somewhere in the system.
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A worn ignition component, restricted airflow, a safety system shutting the furnace down, a control or electrical issue, or something else entirely. The symptom points us in a direction. The diagnosis finds the cause.
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We explain what we found, what needs to be repaired, and whether the repair makes sense for the age and condition of the equipment. We’ll tell you what we think is worth fixing, and what isn’t. A repair should make sense for the system, not just fix the immediate problem.
Not every failed furnace needs to be replaced. And not every furnace is worth repairing.
The goal isn’t just to get the heat running again. It’s to find what caused it to stop working properly in the first place.
We’ll explain what we found and recommend the approach that makes the most sense for your system.
A dusty smell at the start of heating season is normal — dust burns off after sitting all summer. That should clear within an hour or two. A burning electrical smell is different — shut it down and call someone. A gas smell means turn everything off, leave the house, and call your gas company before you call us. Don’t flip any switches on your way out.
If your furnace has a standing pilot light, a failing thermocouple is the most common cause, though drafts or buildup around the pilot assembly can also prevent it from staying lit. If relighting it doesn’t work, there’s usually an underlying problem that needs attention. Many newer furnaces don’t have a standing pilot at all—they use electronic ignition. If your furnace won’t ignite or repeatedly fails to start, we can diagnose the cause and recommend the appropriate repair.
Age alone isn’t a reason to replace a system. What matters is whether parts are available, whether the repair makes financial sense, and whether the system is safe to operate. We work on older systems regularly and will tell you honestly whether a repair is worth doing or whether the money is better spent on a replacement.
If the repair makes sense and the system is in otherwise good shape, fix it. If it’s older, needs a major component, or has been requiring repeated work, replacement usually starts making more sense — especially with California incentives on qualifying systems. We look at the condition of the system, the repair itself, and how much more life the equipment realistically has left. We’ll tell you what we’d do if it were our own house.
Yes. Every home with a gas furnace should have working carbon monoxide detectors installed according to the manufacturer’s recommendations and local code. Carbon monoxide is colorless and odorless, so you can’t see or smell it. If a detector goes off, leave the house immediately and call 911. If your furnace is found to be the source, we’ll inspect it, identify the cause, and recommend the appropriate repair.
A furnace may blow cold air because of a thermostat setting, ignition problem, dirty flame sensor, restricted airflow, or a safety control shutting the burner down. Start by checking the thermostat and making sure the pilot is lit. If those look fine, get it diagnosed before more damage happens.
A furnace that keeps turning on and off is usually caused by restricted airflow, an overheating heat exchanger, or a failing flame sensor. A clogged filter is the easiest place to start. If that’s not the issue, get it looked at — an overheating heat exchanger is a serious problem that can crack over time and create a carbon monoxide risk.
Whether your furnace won’t fire, the house isn’t warming evenly, or something just doesn’t seem right, we’ll diagnose the problem, explain what we found, and tell you whether the repair makes sense.