A new furnace or heat pump, sized for your house rather than matched to the old one. Free in-home estimate.
Estimates
Serving Phoenix, AZ
# ROC 102297
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CMI-AIR installs and replaces furnaces, heat pumps and packaged units across Phoenix and the Valley.
Heating replacement here comes with a question most of the country does not have to think about. Phoenix runs its heat for a few weeks a year and its cooling for five months, so a heat pump, which does both with one piece of equipment, is genuinely competitive with a separate furnace. We price both when it is a real choice rather than steering you to one.
Most people arrive here for one of these reasons.
This is the one heating problem that is not a repair conversation. A cracked heat exchanger can put combustion gases into the air circulating through your house, and the correct response is to take the furnace out of service. If a tech has told you your heat exchanger is cracked, get a second opinion if you want one, then replace the furnace.
Phoenix furnaces last a long time because they run so little, so age alone is a weaker signal here than it would be elsewhere. Past twenty years though, parts availability starts to be the problem, and a system that needs an obsolete control board is a system waiting to strand you.
One flame sensor is a repair. The same furnace failing every December is a pattern, and it usually means several components are near the end of their life at once, or something structural was wrong with the installation.
If the upstairs or the far end of the house has never heated properly, a bigger furnace will not fix it. The cause is almost always duct distribution, and it needs to be diagnosed before you buy equipment, not after.
If the AC is being replaced and the furnace shares the same air handler, doing both at once costs less than two separate jobs and it guarantees the indoor and outdoor equipment are matched. This is the most common reason heating installation happens in Phoenix.
Some homeowners want a heat pump instead of a gas furnace, either to simplify to one system or to move the house to all-electric. Phoenix is one of the better climates in the country for that, because heat pumps lose efficiency in genuinely cold weather and we rarely get there.
Adding conditioned square footage without adding capacity leaves the whole house short. Sometimes the answer is a larger system, sometimes it is a ductless unit dedicated to the new space. That depends on the duct layout and the load.
A heat pump makes sense for most Phoenix homes replacing both systems at once. A furnace makes sense if you are keeping a working air conditioner, if the house already has gas service you want to use, or if you want heat that comes up fast on the coldest mornings.
Here is the actual difference.
A heat pump is an air conditioner that can run in reverse. One outdoor unit does cooling in summer and heating in winter. It is efficient, it uses no gas, and in a climate this mild it rarely runs into the cold-weather limits that make heat pumps a compromise elsewhere. The trade-off is that it runs the same compressor year round, so it accumulates hours faster than a furnace and its service life tracks closer to an air conditioner’s.
A gas furnace produces heat quickly and does not care how cold it gets outside. It runs so few hours in Phoenix that it commonly lasts [15] to [20] years. The trade-offs are that it needs an annual combustion safety check, it needs a flue, and it is a second piece of equipment to maintain alongside the air conditioner.
A dual fuel setup pairs a heat pump with a gas furnace and switches to gas on the coldest days. It is more equipment and more money, and in Phoenix it is rarely worth it, because the number of days cold enough to need the furnace is small.
With a load calculation on your house, not by matching the nameplate on the old unit.
A Manual J calculation accounts for square footage, insulation, window area and orientation, ceiling height, duct location and how many people live there, and it produces the actual heating load in BTUs.
Oversizing a furnace is the common mistake, and it causes real problems. An oversized furnace heats the air fast, satisfies the thermostat, and shuts off before the house has evened out. You get short cycling, warm and cold spots, more wear on the ignition components, and a house that never feels settled. It also runs at its least efficient point, because most of a furnace’s inefficiency is in the start-up and shut-down of each cycle.
Matching the old unit repeats whatever mistake was made last time, and it ignores any insulation, window or square footage changes since.
A tech looks at the existing equipment, the ductwork, the flue, the gas line and the electrical panel, then runs the load calculation. [60 to 90] minutes, free, written quote [same day or next day].
[Two or three] options at different efficiency levels, each with the installed price and the efficiency rating. Where a heat pump is a real alternative you will see it priced next to the furnace rather than mentioned in passing.
We pull the [City of Phoenix or applicable jurisdiction] mechanical permit. Gas work and flue work are both inspected.
Old equipment removed and hauled away. New unit set, gas line connected and leak tested, flue connected and drafted, condensate routed on a high-efficiency unit, electrical connected, thermostat installed and configured. Most single-system replacements are one day.
Gas pressure set to the manufacturer’s spec. Temperature rise across the heat exchanger measured and the blower speed adjusted to bring it inside spec. Combustion tested. Full heat cycle run and safe shutdown confirmed. You get the readings in writing.
We register the equipment with the manufacturer so the warranty is valid, and we handle the [municipal] inspection.
Call (602) 437-0066 or use the form. If you currently have no heat, tell us, and we will look at getting you through the immediate problem before talking about replacement.
Commonly [15] to [20] years, and sometimes longer, because it runs so few hours here. That is longer than the same furnace would last in a cold climate, and considerably longer than an air conditioner lasts in this one. Heat pumps are different, and track closer to AC lifespans because they run year round.
Often yes, if both are near the end of their life and they share the air handler. One visit costs less than two, and you end up with matched equipment. If the furnace has years left, keep it, and we will quote the cooling side on its own.
For most homes replacing both systems at once, yes. Phoenix rarely gets cold enough for a heat pump to lose efficiency, and one piece of equipment covering both seasons is simpler to own. If you are keeping a working air conditioner, a furnace is the straightforward answer.
One day for most straightforward replacements. Two days if the flue or gas line needs rerouting, the electrical needs upgrading, or the equipment is being relocated.
Yes. A mechanical permit and an inspection, and gas and flue work are part of that inspection. We pull it and handle it. Any contractor offering to skip the permit on a gas appliance is telling you something worth knowing.
Higher than the minimum, but the payback math here is different from the cooling side. A furnace running a few weeks a year takes much longer to earn back an efficiency premium than an air conditioner running five months. We will show you the difference rather than pushing the top of the line by default.
Yes. Having gas service does not commit you to a gas furnace. Some homeowners keep the gas for water heating and cooking and move space heating to a heat pump. We will price it both ways.
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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