Should you repair or replace your air conditioner?

Start with three facts: how old the AC is, what failed, and what the repair costs compared with a new system. A small repair on a younger unit is almost always worth doing. A large repair on an older unit rarely is.

ENERGY STAR suggests you consider replacement once an air conditioner is more than 10 years old. That is a prompt to run the numbers. It does not mean a unit of that age is finished. The repair or replace calculator combines age, the repair quote and a few other signals into one result.

• The failed part is minor. Capacitors, contactors, fan motors and clogged drain lines are routine repairs.
• The parts warranty is active. The manufacturer pays for the part and you pay for labor.
• This is the first real repair. One failure in many years of service is normal.
• The system cools evenly and your bills are steady. The rest of the equipment is doing its job.

• The compressor or a coil has failed out of warranty. These are the most expensive parts in the system, and the labor is heavy.
• The unit runs on R-22. R-22 has not been made or imported in the US since January 1, 2020, so any repair that needs refrigerant depends on a shrinking reclaimed supply. See the guide to the R-22 and R-410A phase-out.
• Repairs keep coming. ENERGY STAR lists frequent repairs together with rising energy bills as a sign to replace.
• Comfort problems that repairs have not fixed. Rooms that stay too hot, humidity problems and a noisy system are also on the ENERGY STAR list.

ENERGY STAR says a correctly installed high-efficiency unit can save up to 20 percent on heating and cooling costs. Your result depends on how old and how inefficient the current unit is.

Replacing only the outdoor unit. The outdoor unit and indoor coil are designed as a matched pair. EPA guidance allows a faulty component on an existing R-410A system to be replaced with a similar component. Replacing both the condensing unit and the indoor coil counts as a new system, which must use a newer refrigerant. Ask the contractor which refrigerant the quoted equipment uses.

You plan to move soon. A repair that keeps a working system running can be the sensible choice. A dead system can hurt a sale.

It failed in a heat wave. Urgency pushes people into the first quote they get. If the home is unsafe for someone in it, get a temporary fix or portable cooling and still collect a second quote.

An older unit with a cheap fix. Age alone is no reason to replace. If the repair is minor and the unit has been reliable, fix it and start saving for the replacement. The guide on how long an AC lasts covers what wears a unit out.

You cannot confirm a failed compressor, a refrigerant leak or a bad coil yourself. Ask the technician for a written diagnosis that names the failed part and how it was tested. Then ask for the repair price and a replacement price on the same visit.

A replacement quote should list the equipment model numbers, the size in tons, the SEER2 rating, the refrigerant, what happens to the existing ducts and line set, permits, and the labor warranty. The guide to AC replacement cost explains each line.