Repair it, or replace it?

A system that is not running at all is not a repair-or-replace question yet — it is a diagnosis question. Until somebody knows why it stopped, any figure you are given for replacing it is a figure produced without information.

• In a building, ask what has failed before you ask what it costs.
• In a house, check the breaker and the filter first. It is free and it is often the answer.
• A quotation to replace, offered before the fault is found, is a sales call.

Repeated failures inside two years are rarely bad luck and they are almost never fixed by a new machine. Something upstream is doing the damage — airflow, electrical supply, drainage, controls fighting each other, or a component that was the wrong specification when it went in.

• Replacing the unit without finding the cause reproduces the fault on newer equipment.
• Ask for the previous failures in writing. The pattern is usually visible in them.
• This is the outcome where we most often tell people not to spend the big money yet.

Running, not failing repeatedly, and under fifteen years old. On that evidence it is a repair. Equipment of that age generally still has parts, still has value, and is not the place the next budget cycle should be spent.

• Keep it on a schedule; most of what shortens plant life is skipped maintenance.
• Record the numbers each visit so a real trend exists when the question comes round again.
• Spend the money on ducts, controls and airflow, which usually return more than new plant would.

Past fifteen, and supply is getting difficult. The risk here is not the cost of the repair, it is the wait: an obsolete part on back-order in July is a building without cooling for however long the lead time turns out to be.

• Budget for it now, so the decision is not made under pressure on the day it dies.
• Get the survey done while it is still running — access, curb and electrical supply are much easier to establish on a working unit.
• Where the building cannot tolerate an outage at all, bring the replacement forward rather than gambling.

Past fifteen, but still supportable and not failing repeatedly. This is the comfortable case, and it is the one where planning is worth most: you have time to phase it across budget years, to do it in your own hours, and to get competing prices properly.

• Survey now, replace on your schedule rather than on the weather’s.
• A phased renewal across two or three years usually beats one emergency.
• Use the time to fix the ductwork, which is far cheaper while the plant is off anyway.