HVAC · Service

AC repair — and when to stop repairing

What usually breaks, what it takes to fix, and the point where another repair is money you will not get back. Matched with vetted local HVAC pros, free.

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In short

What is ac repair?

Most air conditioning failures come down to a handful of parts: a failed capacitor, a burnt contactor, a clogged condensate drain, a dirty coil restricting airflow, or a refrigerant leak. The first four are ordinary repairs on any system. The last one is the decision point — a leak on a system past twelve years is usually where repairing stops being worth it.

Triggers

Signs you need ac repair

The unit hums but the outdoor fan does not spin — often a capacitor, one of the cheapest common failures
Air is coming out of the vents but it is not cold
The system turns on and off every few minutes without ever satisfying the thermostat
Ice on the refrigerant line or on the indoor coil — almost always airflow restriction or low refrigerant
Water pooling around the indoor unit, or a ceiling stain below it
A grinding, screeching or rhythmic clicking noise that was not there last season
The breaker for the condenser trips and needs resetting more than once
Cooling is fine, but your electricity bill has climbed with no change in the weather or your habits

Seeing something not on this list? Browse hvac problems by symptom →

The job

How ac repair actually works

Diagnostic visit

The technician confirms the symptom, checks the thermostat and the filter first, then works electrical and refrigerant side: capacitor and contactor condition, amp draw, static pressure, superheat and subcooling. Most diagnoses are reached in under an hour.

Watch for: A diagnosis delivered without any instrument on the equipment. If nobody put gauges or a meter on it and you are being quoted a compressor, get a second opinion before agreeing to anything.
The diagnostic fee conversation

Nearly every company charges to come out and diagnose. Many credit it against the repair if you go ahead. Ask which policy applies before booking, and ask whether the fee changes for evenings and weekends.

Watch for: A "free" diagnostic. Diagnosis costs the company real time, so a free one is usually recovered somewhere — most often in a repair quote that arrives higher than it needed to be, or in a replacement pitch.
The repair quote, itemised

You should get the part, the labour and the warranty on that repair separately. Common repairs — capacitor, contactor, condensate pump, blower capacitor, clearing a drain line — are modest. Compressor and evaporator coil replacements are an entirely different order of expense.

Watch for: A single lump-sum figure with no part named. You cannot judge whether a price is reasonable, or get a comparable second quote, without knowing what is being replaced.
Refrigerant: the question to insist on

If the system is low on refrigerant, it has leaked, because refrigerant is not consumed. Adding more without finding the leak buys you a season at most. Ask for a leak search — dye, electronic detector or nitrogen pressure test — and for the leak location in writing.

Watch for: A "top-up" offered as the fix, especially as an annual routine. That is a recurring charge dressed up as maintenance. It is also poor practice environmentally, and on older R-22 systems it is expensive enough on its own to change the repair-or-replace answer.
Repair or replace — the actual threshold

Two things decide it: the age of the system and the size of the repair relative to a new one. Under about ten years, repair almost always wins. Past fifteen, a major repair rarely does. In between, weigh the repair cost against what you would pay for a system that comes with a fresh warranty and lower running cost.

Watch for: A replacement recommendation on the first visit for a system under ten years old, with no part diagnosis offered. That is a sales call with a toolbox.

Money

What does ac repair cost?

Most air conditioning repairs land between $150 and $700, with capacitors and contactors at the low end and refrigerant leak repair or an evaporator coil at the top. Compressor replacement sits well above that and is usually where replacement becomes the better buy.

See the full ac repair cost guide — by material, size and region →

Straight answer

When ac repair is the wrong call

Everyone else ranking for this is paid when you say yes. Here's when you shouldn't.

The filter is filthy and nobody has changed it. A blocked filter starves airflow, freezes the coil, and produces symptoms that look exactly like a refrigerant problem. Change it, let any ice thaw fully, and try again before you pay a call-out fee.
The system is past fifteen years and needs a compressor or an evaporator coil. You would be spending a large fraction of a new system on the two components most likely to be followed by another failure, on equipment with no warranty left.
It still uses R-22. Refrigerant for these systems is scarce and priced accordingly. A leak repair that would be routine on a modern system can cost more than the equipment is worth. Price the replacement before authorising the repair.
This is the third repair in two summers. Add up what you have already spent. Homeowners routinely spend more on a sequence of repairs than a replacement would have cost, because each individual repair looked reasonable in isolation.
The real complaint is that one room is hot. Nothing is broken. That is duct sizing, duct leakage or balancing, and a repair technician replacing parts will not change it.
You were already planning to replace the furnace this year. The indoor coil sits on the furnace. Repairing the AC now and replacing both in six months means paying twice for the same access.

Before you sign

What to check when hiring for ac repair

What is the diagnostic fee, and is it credited against the repair?

Sets expectations before anyone is in your driveway, and tells you a lot about how the company prices.
Which specific part has failed, and can you show me?

A named part is checkable. A failed capacitor is visibly bulged; a burnt contactor is visibly burnt. Vague answers are worth a second opinion.
If it is low on refrigerant, where is the leak?

The most important question on the page. Refrigerant does not get used up. No leak location means no repair, just a temporary top-up you will pay for again.
What warranty comes with this repair, on parts and on labour?

A short or absent warranty on an expensive repair is the company telling you how confident it is in the outcome.
How old is my system, and what would replacement cost?

Not because you should replace — because you cannot judge whether a repair is good value without the number it is being compared against.
Are you licensed and insured in this state, and can I see it?

Refrigerant handling is federally regulated and the electrical side is genuinely dangerous. This is a reasonable thing to ask, and a reasonable company answers it easily.

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Local pros

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Related work

Often done at the same time

Emergency HVAC Repair

After hours, and whether it can wait

HVAC Maintenance

The repairs you can avoid

AC Installation

When repair stops making sense

HVAC Replacement

Heating and cooling together

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Go deeper

Guides & terms

Guides

HVAC Repair vs Replace

All hvac guides →

Terms on this page

Refrigerant

Full hvac glossary →

FAQ

AC Repair — questions people ask

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Why is my AC running but not cooling?

The three common causes, in order of how often they turn up: a restricted filter or blocked return starving airflow, a refrigerant leak that has dropped the charge, and a failed capacitor leaving the compressor unable to start while the indoor fan carries on blowing. Check the filter yourself. If it is clean and the outdoor unit is running but the line is not cold, it needs a technician.

How much does AC repair cost?

Most repairs fall in the low hundreds — capacitors, contactors, blocked condensate drains and thermostat faults are all routine and inexpensive. Refrigerant leak repair, evaporator coils and compressors are substantially more, and it is at that tier the repair-or-replace question becomes real. Expect a separate diagnostic fee, often credited against the work if you proceed.

Is it worth repairing a 15-year-old air conditioner?

For a small repair, yes — spending a couple of hundred dollars to get another season is fine. For a major one, usually not. At that age the warranty has expired, efficiency has fallen behind current equipment, and the components most likely to fail next are the expensive ones. Get a replacement quote alongside the repair quote and compare them properly rather than deciding under pressure on a hot day.

Does my AC need a refrigerant recharge every year?

No. A sealed system does not consume refrigerant. If it is low, it is leaking. Annual recharging is a leak being managed rather than fixed, and you are paying for the same refrigerant repeatedly. Insist on a leak search and a written location. If a company offers yearly top-ups as a normal service, that tells you what to expect from them.

Why does my AC freeze up?

Ice forms when the evaporator coil gets too cold, which happens either because airflow across it is restricted or because the refrigerant charge is low. Restricted airflow is the more common and the cheaper — a clogged filter, a dirty coil, closed or blocked vents, or a failing blower. Turn the system to fan-only to thaw it completely before anyone works on it, and never chip at the ice.