A repair call is useful information, but the call is not the decision. Before you approve any repair on an older system, ask the questions below in order. They work the same way whether the system is a furnace, a dishwasher, a garbage disposal, or a garage door opener.
Start with the age. Find the install year on the unit or in your records, and compare it with the planning window for that system on this site. If the system is inside its window, a repair is often the right first step. If it is near or past the window, the repair becomes a question about how much service life is left, and you should ask that question directly.
Next, ask the technician what failed, what part is needed, and whether that part is still made for your unit. Ask whether the repair restores the system or only moves the problem to a later visit. Ask the technician to name anything else they saw that is wearing, even if it is not part of the order in front of you. A plain answer is more useful than a long one.
Then ask about the paperwork. Ask for the repair in writing, with the part named, the labor described, and the terms of any warranty on the work spelled out. Ask what the estimate excludes. If a service contract is involved, read its waiting period, which is the stretch after the contract starts during which certain claims are not yet covered. Read its cancellation terms, and check what it says about the repair you are authorizing before you sign. Do not accept a verbal promise that a claim will be paid.
Last, compare the repair against the replacement plan before you commit. If the repair is large relative to the age of the system, ask what a replacement would involve and how long it would take to arrange. Keep the answers in one place so the next decision starts from notes rather than memory. For the typical service life of the appliances in your home, the ranked appliance list on this site is a planning reference, not a verdict on any unit.