Furnace and heat pump repair, installation and maintenance. [Same-day appointments available.]
Serving Phoenix, AZ
# ROC 102297
Rated by BBB
and after hours availability
CMI-AIR repairs, installs and maintains residential heating across Phoenix and the Valley. Furnaces, heat pumps and the heating side of packaged units.
Phoenix heating gets treated as an afterthought, and that is exactly why it fails when it is needed. A furnace here runs a handful of weeks a year and sits idle the rest, and equipment that sits idle for ten months develops different problems than equipment that runs constantly. Dust settles on the burners and the heat exchanger. Rodents get into cabinets and chew wiring. Igniters and flame sensors corrode. Then the first cold snap arrives in December, the system is asked to work for the first time since February, and it does not.
No heat, weak heat, a system that will not ignite, or one that starts and shuts down. We diagnose it and quote the repair before we start.
New furnace or heat pump, sized and installed properly. Often done alongside an AC replacement since they share the air handler.
Three types, and the right service approach differs for each.
Gas furnaces. Common in older Phoenix housing stock. Natural gas burners, a heat exchanger, and a blower that shares the duct system with the air conditioner. These need an annual safety check, because a cracked heat exchanger is a carbon monoxide risk and it is not something a homeowner can see.
Heat pumps. Increasingly common in newer builds and in all-electric homes. A heat pump is an air conditioner that can run in reverse, which makes it efficient in a mild winter climate like ours. Phoenix is close to ideal for heat pumps, because we rarely get cold enough for one to lose efficiency. They do run the same compressor year round though, so run hours accumulate faster.
Packaged units. Heating and cooling in one cabinet, usually on the roof. Common on flat-roof homes here. Service access is different and so is the failure pattern.
If you are not sure which one you have, we can tell from the equipment location and a photo.
Because idle equipment develops problems that running equipment does not. Five common ones.
Dust on the burners and heat exchanger. Ten months of the blower pushing desert dust through the cabinet leaves a layer on everything. On first ignition it burns off, which is the smell people notice in December, and heavy buildup can cause uneven combustion or nuisance shutdowns.
Corroded flame sensors and igniters. These are the single most common no-heat call. A flame sensor coated in residue cannot confirm the burner lit, so the control board shuts the gas off as a safety measure. The system tries a few times and locks out.
Rodent damage. Warm cabinets in an attic or a garage are attractive in winter, and wiring gets chewed. This is more common in Phoenix than most people expect.
Blocked or disconnected flue. Roof work, storm debris, or nesting. This one matters because it is a combustion safety issue rather than a comfort issue.
Stuck blower or seized motor. A blower that has not moved in months, with dust-loaded bearings, sometimes does not start.
All five are what a fall maintenance visit is for.
October or November, before the first cold night. That is the whole answer.
The pattern here is predictable. The first genuinely cold week of the year produces a wave of no-heat calls, all from homes where the system had not been touched since the previous winter. Booking in fall means the problems get found on a day when the house is comfortable and a part can be ordered without anyone being cold.
If you also have us out for AC maintenance in spring, that is two visits a year and it covers both systems on the right schedule.
Heating maintenance in Phoenix is a safety visit first and a comfort visit second. That is the honest framing, and it is different from how AC maintenance works here.
The efficiency argument for a furnace tune-up is weak in this climate, because the system runs a few weeks a year. The safety argument is not weak at all. A gas furnace burns fuel inside your house and vents the products of that combustion through a flue, and what keeps those gases out of the air you breathe is an intact heat exchanger and a clear flue. Neither is something a homeowner can inspect.
One thing we will not do is put a system back into service that we have found to be unsafe without telling you clearly what we found and why. If the heat exchanger is cracked, you will hear it plainly, along with what your options are.
If you have a gas furnace, this section matters more than anything else on this page.
A cracked heat exchanger can let combustion gases into the air the blower circulates through your house. It is not visible from the outside of the cabinet and it does not announce itself. Testing for it is part of every heating maintenance visit we do.
Install a carbon monoxide detector on every level of the home if you do not have them, and replace them on the manufacturer’s schedule, since the sensors expire. If a CO detector sounds, leave the house and call the gas company or 911 before you call us.
Signs worth calling about: a yellow rather than blue burner flame, soot around the furnace, a persistent smell when the heat runs, or headaches and nausea that appear when the heat is on and clear when it is off.
Phoenix, Scottsdale, Mesa, Tempe, Chandler, Glendale, Gilbert, Peoria, Surprise, Avondale, Goodyear, Ahwatukee, Paradise Valley, Cave Creek and Queen Creek.
Call (602) 437-0066 or use the form. If you have no heat and the overnight low is [below 40], tell us and we will treat it as urgent.
Flame sensor and igniter replacement. Both are inexpensive parts, both corrode or foul during the ten months the system sits idle here, and both stop the furnace from confirming the burner lit, which makes the control board shut the gas off. They account for a large share of the no-heat calls we run every December.
For a gas furnace, yes, and the reason is safety rather than efficiency. The heat exchanger and combustion check is the point of the visit. For a heat pump, annual service is worth it because the same compressor runs year round and it accumulates hours faster than a furnace does.
For a gas furnace, yes. A cracked heat exchanger does not stop a furnace producing heat and it does not announce itself. A furnace can run perfectly and still need to come out of service. That is the specific thing the visit looks for.
It is the difference between the air going into the furnace and the air coming out, and every furnace has a range it should fall inside. Too high means airflow is restricted and the heat exchanger is running hotter than it should, which shortens its life. Too low means the blower is moving too much air for the burner. Correcting it is usually a blower speed adjustment.
Slightly, and less than AC maintenance lowers your electric bill, because the furnace runs a fraction of the hours. If somebody is selling you a furnace tune-up on energy savings in Phoenix, the safety argument is the real one and it is the one worth paying for.
Dust burning off the heat exchanger and burners after months of sitting idle. It is normal on the first run of the season and should clear within an hour. If the smell is sharp, chemical, or smells like gas, shut the system off and call.
Longer than an air conditioner does here, often [15] to [20] years, because it runs so few hours. Heat pumps track closer to AC lifespans since they run year round.
Yes. Heat pumps lose efficiency in genuinely cold weather and Phoenix rarely gets there, so this is one of the better climates in the country for one. If you are replacing both heating and cooling at the same time, a heat pump is worth pricing against a furnace and AC pair.
Usually the flame sensor. The burner lights, the sensor fails to confirm it, and the control board shuts the gas off as designed. It tries a few times and then locks out. It is one of the cheapest and most common heating repairs there is.
CMI-AIR is the residential division of Consolidated Mechanical, a local, family-owned commercial air conditioning company with more than 30 years of experience.
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