AC repair questions, answered

Send a request here or call (520) 666-4679. We pass it to one independent HVAC company that serves your ZIP and holds an Arizona Registrar of Contractors license for air conditioning work. They call you back, diagnose the system and give you a price before any work starts.

Published 2026 national figures put most AC repairs at $250 to $700, with a $375 average (Fixr), or $150 to $650 for common fixes (This Old House). A capacitor sits at the low end; a compressor runs $600 to $3,000 or more. Prices in Mesa vary by company, so get the price before work starts.

This Old House puts the typical life of a home cooling system at 12 to 15 years. An Arizona system runs more hours than most, so plan on the low end of that range, and on a replacement price once it passes 10 years and needs a big repair.

Maybe not. On a 115 degree afternoon the house can drift up even while the system runs nonstop. If it can't catch up overnight, when Sky Harbor's July low now averages about 87°F, or the air at the vents isn't cold, something is wrong. A dirty filter or a weak capacitor are common causes. So is low refrigerant from a leak.

An independent HVAC company that serves your ZIP and holds an Arizona Registrar of Contractors license. Mesa Cooling Pros is a referral service; we pass along your request so you don't have to call around. You can check any contractor's license at roc.az.gov.

Multiply the system's age in years by the repair quote. If the result is over $5,000, This Old House suggests replacement is worth pricing. It is a rule of thumb: a cheap repair on an old system that otherwise runs well is often still the right call.

After the compressor shuts off, give it a few minutes before it starts again so the pressures in the system can even out. Many thermostats enforce this on their own; Honeywell's RTH2300 manual says its built-in compressor protection makes the compressor wait 5 minutes, and the screen flashes while it waits.

On the outdoor unit, the capacitor. It helps start the compressor and fan motor, and long run hours in the heat wear it out. Fixr lists capacitor replacement at $100 to $400. Contactors, fan motors, clogged drain lines and refrigerant leaks are the other usual suspects.

Warm air from the vents. The usual causes are a failed capacitor or fan motor outside, a frozen coil from a dirty filter, a refrigerant leak, or a thermostat set to fan only. Check the filter, the breakers and the thermostat first.

We haven't found a reliable source with a 2026 figure for the Mesa area. Two things changed: new home systems built with components made from January 1, 2025 must use lower-GWP refrigerants such as R-32 or R-454B (EPA), and the federal 25C tax credit ended for equipment placed in service after December 31, 2025 (IRS). Get two quotes on any replacement.

Stick to the safe checks: thermostat set to cool with fresh batteries, breakers for both units, a clean filter, and a clear outdoor coil. If there is ice, turn the system off with the fan on. Leave the electrical panel and refrigerant to a licensed technician; capacitors hold a charge even with the power off.

An HVAC technician (heating, ventilation and air conditioning). In Arizona the company they work for needs a Registrar of Contractors license for air conditioning work, such as the residential R-39 or the dual CR-39 classification, unless the job is under $1,000 and needs no permit.

We don't rank companies. What matters is checkable: a current Arizona ROC license for HVAC work, a written price before work starts, a clear warranty on parts and labor, and no pressure to replace a system for a repair the published price tables put in the hundreds.

This Old House lists an AC tune-up at $65 to $200, with a $133 national average (March 2026). A repair visit is priced separately: Fixr puts most repairs at $250 to $700.

The City of Mesa says you don't need a permit if the new unit uses the same or less electricity as the old one, and that changing the electrical connections needs a construction permit. Ask the contractor which applies to your job.

If there's ice on the lines or coil, yes: set it to off with the fan on so it thaws. If the outdoor unit hums but won't start, turn it off and call. Running it can make the damage worse.

Call 911 for a medical emergency, such as signs of heat stroke. For the broken system, call an HVAC company. For a cool place to go, dial 2-1-1.

No. EPA says the rule doesn't limit the use of existing systems, and you can keep repairing them, including with R-410A replacement parts.

Only systems whose components were all made or imported before January 1, 2025, under EPA's May 2026 reconsideration rule. Systems built with newer components must use refrigerant under 700 GWP.

Fixr's 2026 national figures are $250 to $700 for most repairs, with a $375 average. This Old House says most homeowners pay $150 to $650 for common fixes.

Fixr lists a new central system at $5,800 to $14,400 installed, with an $8,750 average. Size and ductwork drive the price.

Most of the bill is the trip and the technician's time. This Old House puts a capacitor itself at $8 to $45.

Common causes are a failed capacitor or fan motor on the outdoor unit, a frozen indoor coil from a dirty filter, low refrigerant from a leak, or a thermostat set to fan only. Check the filter and the breakers first.

A weak or failed capacitor is the usual cause. It holds an electrical charge even with the power off, so leave it to a technician.

It can. EPA says to use as high a MERV rating as your system fan and filter slot can accommodate, and to ask an HVAC technician what that is. A filter the fan can't pull enough air through cuts airflow, and low airflow can freeze the indoor coil. In a Mesa summer a clean filter the system can breathe through matters more than the highest rating.

No. This site is for home air conditioning and heating. For a car or truck, you need an auto repair shop.

If it needs a major repair, usually yes. If it runs fine and only needs a small part, repairing it and planning a replacement is reasonable.

Rarely. Fixr lists compressor replacement at $600 to $3,000, and on a system near the end of its life that money usually goes further toward a new one.

Fixr's national average for a new central system is $8,750, based on a 3 ton, 16 SEER split system with new ductwork in a 2,000 sq ft home. A 3 ton system alone runs $5,000 to $9,150 installed. The right size for your house comes from a load calculation.

No. The IRS says the 25C credit isn't allowed for property placed in service after December 31, 2025. Ask about current SRP rebates instead.

Installation matters more than the badge on the unit. Correct sizing, sealed ducts and the right refrigerant charge come first. Pick the contractor first, then compare the warranty each brand comes with.

A rule-of-thumb estimate of 20 BTUs per square foot gives about 40,000 BTUs, or roughly 3 to 3.5 tons. A Manual J load calculation should set the final size.

Once a year, in spring. A heat pump that also heats the house gets used year-round, so some owners check it again in fall.

It can be, if it includes a real spring check with readings and you would otherwise skip maintenance. Read the renewal and cancellation terms before signing.

A Registrar of Contractors license whose classification covers air conditioning. For homes that is usually the residential R-39 or the dual CR-39 (or CR-79). A commercial-only C-39 doesn't cover residential work.

Only small jobs. A.R.S. 32-1121 exempts work under $1,000 total that needs no building permit. Anything bigger needs a licensed contractor.

At roc.az.gov, the Arizona Registrar of Contractors. The search shows whether the license is active and what it covers, along with any complaints.

Fixr's national figures are $300 to $700, with a $500 average. Duct repair and sealing are priced separately.

Only when there is a reason: mold, pests, remodel debris, or dirt blowing out of the registers. Changing the filter often does more for dust than routine cleaning.

In summer it can be, especially for older adults and babies. Maricopa County found that in 2025 indoor heat deaths, the AC was present but not working in most cases. Tell the company who is at home when you call, and move people somewhere cool if the house heats up.

Fans help a little, but the CDC says they won't prevent heat illness when it's really hot, and the National Weather Service says not to point one at yourself above 90°F. An air-conditioned place is safer.

Dial 2-1-1 for cooling locations and heat relief transportation. The county's Heat Relief Network map is at hrn.azmag.gov, and the City of Mesa lists its sites on its heat safety page. Most sites run only in the summer season, so check what is open.

Dust on the heat strips or furnace burns off the first time it runs each season, and the smell should fade within a short while. If it keeps smelling, or smells like gas, turn it off and call.

Fixr's national figures are $349 to $650, with a $485 average.

Yes. Winter lows in the valley are mild by national standards, which is the easy case for a heat pump. Most systems here also have backup heat strips for the occasional cold morning.

Fixr's 2026 national figures are $5,000 to $15,000, with an $8,350 average. Size and ductwork drive most of the price.

It may be in a normal defrost cycle, which lasts a few minutes. If it keeps blowing cold, a reversing valve or defrost control is a likely cause. So is a thermostat set up for the wrong system. Call for service.

It is well above the published ranges. This Old House lists capacitor replacement at $80 to $400 installed and Fixr at $100 to $400. Ask what else is included, and get the itemized quote in writing.

It is above Fixr's published range of $5,800 to $14,400 for a new central air system. A quote that high should explain what is included, such as new ductwork or two systems. Get a second quote.

If the seller came to your home without an invitation, Arizona law allows cancellation until midnight of the third business day after signing. The FTC rule doesn't cover a repair visit you asked for. It may cover extras you add beyond that repair. This is general information, not legal advice.

The Department of Energy says to set it as high as is comfortable when you're home and awake, and higher when you're asleep or away. A ceiling fan lets you go about 4°F higher without losing comfort.

SRP serves most of Mesa. The City of Mesa runs its own electric utility for a 5.5 square mile area around downtown, according to the city's service area map.

Usually a packaged unit, often a heat pump, sitting outside the home and connected to ducts under the floor. Some have split systems or evaporative coolers.

A crushed or disconnected duct under the floor is a common cause. Ask the technician to check the belly ducts, not just the unit.

Check whether the park has rules about outside contractors first. Then request service here; the company will confirm they work in your community.

Fixr's national figures are $4,577 to $8,328 installed, with a $6,357 average. A single room is usually at the low end.

Yes, if it is sized for the real load and the garage has some insulation, especially in the door. Ask for a load calculation rather than a size picked from the square footage.

Arizona law (A.R.S. 33-1361) gives five days after written notice for a problem that materially affects health and safety, and the Attorney General has said landlords must act within five days when temperatures pose a health and safety risk. This is general information, not legal advice.

The Attorney General's April 2026 release names Phoenix and Tucson for the 82 degree limit. We found no Mesa city equivalent, so state landlord-tenant law is what applies in Mesa.

Not as a general rule. A.R.S. 33-1364 says the tenant's rights under that section do not include the right to repair. Talk to the landlord or a tenant help resource first.

On many Honeywell thermostats it means the compressor protection delay is running. It stops flashing when the compressor turns on.

The same math works as a first check. Heat pumps run in summer and winter, so they collect hours faster than an air conditioner of the same age.