Repair or Replace Your Air Conditioner

Start with age and refrigerant

Before anyone looks at the fault, two pieces of information do most of the work in this decision, and both are on the nameplate of the outdoor unit.

The first is age. In this climate a split system leads a harder life than the same unit in Toowoomba, and near the water harder again. A unit under roughly eight years old that has been looked after is generally worth fixing. Past twelve or so, every repair is money spent on a machine with a limited remainder regardless of how well the repair goes.

The second is the refrigerant. A system running R22 is on a gas that can no longer be imported into Australia, so any charge has to come from recovered stock. That makes a refrigerant related repair on an old unit both expensive and uncertain, and it is often the fact that decides the question on its own.

Read the nameplate on the outdoor unit before you call anyone. It carries the manufacture date and the refrigerant type, and those two lines will tell you roughly where this is heading.

What has actually failed matters more than the symptom

The same complaint, no cooling, covers repairs at opposite ends of the scale.

Faults sort into two groups, and which group yours is in matters more than what the symptom looked like:

• Component faults, worth repairing on any reasonably aged unit: capacitors, contactors, indoor and outdoor fan motors, control boards, thermistors, drain pumps, blocked drains, dirty coils and filters, failed remotes and sensors
• Sealed system faults, where the decision gets harder: evaporator coil leaks, condenser coil leaks, line set leaks, blocked metering devices, moisture or acid contamination, and compressor failure

Component faults are replaceable at sensible cost, they do not indicate anything about the rest of the system, and replacing one on an otherwise sound unit is straightforward good value. If that is your fault, fix it.

Sealed system faults are different. A leak in an indoor evaporator coil on an older unit usually means the coil is corroding from the inside out, and coil replacement on a discontinued model is frequently more than the machine is worth, assuming the part is still available at all. Manufacturers only support parts for a period after a model is discontinued, and once that window closes the decision is made for you.

The compressor question

A failed compressor is the point where most people should stop and think, and there is a technical reason that rarely gets explained.

When a compressor burns out electrically it does not simply stop. The motor windings break down inside the refrigerant circuit and release acid, which contaminates the oil, the pipework and the indoor coil. Fitting a new compressor into a contaminated system without properly flushing it, fitting a new filter drier and in bad cases replacing the line set, will destroy the new compressor too, and doing it properly voids nothing but takes real time. That is why a compressor replacement done correctly costs what it does, and why one quoted suspiciously cheaply should worry you.

On a unit past ten years old, on an obsolete refrigerant, a burnt out compressor is almost always the end of the conversation.

When repair is the right answer

Plenty of the time it is. A recent unit on R32 or R410A with an electrical component failure, a blocked drain, a dirty coil that is choking performance, or a fan bearing on the way out is worth repairing without hesitation, and we will say so even though a replacement would be the bigger job for us.

What we will not do is take money to charge gas into a system that will lose it again. If a system is low there is a leak, and finding it rather than topping it up is the only version of that job worth paying for. Nor will we rebuild a machine that is already at the end.

If it is worth fixing, see air conditioning repairs in Cairns. If it is not, replacement is usually a chance to correct the sizing that was wrong the first time.