Interactive Guide
Should You Repair
or Replace Your HVAC?
Use our free scoring calculator to evaluate your system, then explore detailed equipment diagrams to understand exactly what's inside your HVAC — and what can go wrong. Already decided to replace? See our HVAC Buying Guide.
Free Scoring Tool
Repair or Replace Calculator
Answer five questions and we'll score your situation using the National Alliance methodology. Takes about 60 seconds.
What type of system are you evaluating?
Understanding the Problem
Four Reasons HVAC Systems Fail
Before deciding to repair or replace, it helps to understand why systems fail in the first place. Most breakdowns trace back to one of these four root causes.
⏰ Equipment Age
Every mechanical system has a lifespan. Over years of operation, normal wear causes component damage and eventual failure. Air conditioners in Phoenix last 12–15 years on average; furnaces may reach 15–20. After that, breakdowns become more frequent and efficiency drops.
🌪 Dirt & Grime
Insufficient filtration lets dust, debris, and allergens accumulate inside your system. This buildup coats coils, clogs drain lines, and damages internal parts — forcing the system to work harder and reducing its lifespan. Arizona's dusty environment accelerates this process.
🔧 Poor Installation
Improper equipment sizing, undersized or leaking ductwork, and incorrect air return placement cause a system to cycle inefficiently from day one. A poorly installed system can lose 20–30% of its rated efficiency and fail years before it should.
🛠 No Maintenance
Preventative maintenance is the single best way to keep a system running efficiently and catch small problems before they become expensive ones. Without regular tune-ups, refrigerant levels, electrical connections, and moving parts degrade unnoticed.
View Maintenance Plans →Equipment Anatomy
Air Conditioning System
Components
- Fan Blade
- Fan Motor
- Circuit Board
- Coil Major
- Metering Device
- Contactor
- Capacitor
- Compressor Major
- Defrost Sensor
- High & Low Pressure Switch
- Line Dryer
- Service Valves
What Can Go Wrong
When an AC condenser fails, the most common culprits are a blown capacitor (cheap fix), a failed contactor (moderate), or a seized compressor (often not worth repairing on older units). Coil leaks caused by corrosion or formicary corrosion are also common in Arizona due to chemical exposure and extreme heat cycling.
Equipment Anatomy
Furnace
Components
- Heat Exchanger Major
- Gas Valve
- Draft Inducer Motor
- Pressure Switch
- Flame Sensor
- Ignitor
- Burners
- Blower Motor
- Capacitor
- Blower Wheel
- Circuit Board
- Transformer
What Can Go Wrong
A cracked heat exchanger is the most serious furnace failure — it can leak carbon monoxide into your home and is often the single most expensive repair. Ignitor and flame sensor failures are common but inexpensive to fix. Blower motor failures fall in the middle. If your furnace is over 15 years old and the heat exchanger is compromised, replacement is the only safe option.
Equipment Anatomy
Air Handler
Components
- Heat Kit
- Circuit Board
- Transformer
- Capacitor
- Blower Wheel Housing
- Blower Motor
- TXV (Thermostatic Expansion Valve) Major
- Blower Wheel
- Drain Pan
- Evaporator Coil Major
What Can Go Wrong
The evaporator coil is the most failure-prone major component in an air handler. In Arizona's hard water and dusty environment, coils corrode and develop micro-leaks over time. TXV failures restrict refrigerant flow and mimic compressor problems. A clogged drain pan leads to water damage if not caught early.
Equipment Anatomy
Heat Pump
Components
- Fan Blade
- Fan Motor
- Circuit Board
- Coil Major
- Metering Device
- Hard Start Kit
- Contactor
- Capacitor
- Accumulator Major
- Compressor Major
- Reversing Valve Major
- High & Low Pressure Switch
- Defrost Sensor
- Line Dryer
- Service Valves
What Can Go Wrong
Heat pumps have more major components than standard AC units because they handle both heating and cooling. A failed reversing valve means the system can only run in one mode. Compressor and accumulator failures are the most expensive repairs. In Phoenix, heat pumps are increasingly popular — but their dual-mode operation means they work harder than a single-purpose unit.
Equipment Anatomy
Package System
Components
- Condenser Fan Blade
- Condenser Fan Motor
- Single Capacitor
- Blower Motor
- Blower Wheel
- Condenser Coil Major
- Contactor
- Evaporator Coil
- Compressor Major
- Pressure Switch
- Accumulator Major
- Reversing Valve
- Drain Line
- Circuit Board
- Dual Capacitor
What Can Go Wrong
Package systems contain everything — condenser, evaporator, and blower — in a single outdoor cabinet. This makes them more vulnerable to weather damage and dust infiltration in Arizona. Condenser coil and compressor failures are the most expensive repairs. Since all components share one housing, a major failure often makes full replacement the practical choice.
Equipment Anatomy
Ductless Mini-Split System
Components
- Condenser Fan Blade
- Defrost Sensor
- Defrost Fan Relay Board
- Capacitor
- Reversing Valve
- TXV
- Condenser Coil Major
- Bi-Flow Liquid Line Drier
- Service Valves
- Fan Motor
- Accumulator
- Compressor Major
What Can Go Wrong
Ductless systems are highly reliable but their sealed refrigerant circuits mean any leak requires specialized recovery and recharge. Compressor failures are the most costly repair. The outdoor condenser coil is especially vulnerable in Arizona's dusty environment — regular cleaning is essential for longevity.
FAQ
Frequently Asked Questions
How do I know if my HVAC system needs to be replaced?
There's no single factor — it's a combination of age, repair cost, energy efficiency, and how long you plan to stay in your home. Our calculator above weighs each factor using the National Alliance scoring method. If your system is over 15 years old and facing a repair over $1,000, replacement almost always makes more financial sense.
What's the average lifespan of an AC unit in Phoenix?
Air conditioners in the Phoenix metro area typically last 12–15 years due to the extreme heat and extended cooling season (6+ months of heavy use). Systems in milder climates can last 15–20 years. Regular maintenance can extend lifespan by 2–4 years.
Is it worth repairing an HVAC system that's over 10 years old?
It depends on the repair. Minor repairs under $500 — like a capacitor or contactor — are usually worth it even on older systems. But major component failures (compressor, heat exchanger, evaporator coil) often cost $2,000–$4,000 to repair, which is 30–50% of a new system. At that point, the investment usually makes more sense going toward a new, efficient unit with a full warranty.
What are the most expensive HVAC repairs?
The four costliest repairs are compressor replacement ($2,000–$3,500), heat exchanger replacement ($2,500–$4,000), evaporator coil replacement ($1,500–$2,500), and condenser coil replacement ($1,200–$2,000). These are the components we flag as 'Major' in our equipment diagrams above. When one of these fails on an older system, replacement usually becomes the smarter investment.
How much can I save on energy bills with a new system?
A modern high-efficiency system (SEER2 17–20) can reduce cooling costs by 30–40% compared to a 10+ year old unit rated at SEER 10–13. In Phoenix, where cooling accounts for 40–50% of your annual energy bill, that translates to $400–$800+ per year in savings — enough to offset a significant portion of the monthly financing payment.
Does DeGeorge offer financing for HVAC replacement?
Yes. We partner with Goodleap, Service Finance, and Wisetack to offer monthly payment plans. Most homeowners qualify for payments starting around $119/month for a basic system and $229–$300/month for a premium variable-speed system. The diagnostic fee ($69) applies toward any approved replacement.
What does the $69 diagnostic include?
Our diagnostic is a comprehensive evaluation — not just a 'look and quote.' We inspect your existing system top to bottom, perform a Manual J load calculation to determine proper sizing, evaluate your ductwork, and present repair vs. replacement options with transparent pricing. If you proceed with any work, the $69 fee applies as a credit toward the total.
Not Sure? Let Us Take a Look.
Book a $69 diagnostic and we'll inspect your system, identify the issue, and walk you through repair vs. replacement options with transparent pricing. The diagnostic fee applies toward any approved work.