Validating or Refuting a Competitor's Proposed Repair
Why this matters
"They say I need a new compressor." "They want to repipe the whole line." "They quoted a new control board." The customer is asking you to confirm or knock down a specific proposed repair, and the honest answer comes from a test, not an opinion. This card is how you independently prove or disprove the exact claim on the table - the part they named, the scope they proposed - so your second opinion rests on evidence the customer can see.
Test the claim they made
A competitor's repair names a component and a fix. Aim your test at that exact claim. If they say the compressor is bad, you are not doing a general once-over, you are answering one question: does this compressor test failed. Confirming or refuting the specific claim is faster, more honest, and more convincing than a vague "I checked it and it is fine."
Prove or disprove the common big-ticket calls
Most disputed repairs are a handful of expensive parts. Each has a test that settles it:
| Claimed failure | The test that confirms or refutes it |
|---|---|
| Compressor or sealed motor | Winding resistance to each terminal and to ground, amp draw vs nameplate; good windings and normal draw refute it |
| Control or circuit board | Prove good inputs (power, sensors) and check for the expected output; a board with good output is not the fault |
| Heat exchanger crack | Visual plus combustion or flue evidence; no crack and clean readings refute a condemn |
| Water heater tank vs part | A leak at a fitting or valve refutes a "bad tank"; a weeping seam confirms it |
| Pool pump motor | Amp draw and bearing or winding check; a motor that runs to spec refutes a full replace |
Treat the table as the shape of the method, not a limit: whatever part they named, find the reading that only a truly failed one could produce, and take it.
A part that tests good does not need replacing
The most common refute is simple: the condemned part passes its own test. A capacitor within its rated microfarads, a motor at nameplate amps, an element reading correct resistance, a board with good output - none of those is a failure, whatever the quote says. When your reading contradicts the claim, capture it, because that number is your whole case. The exception to watch: an intermittent part can test good between failures, so a single good reading refutes a "replace now" only if the fault is not the kind that comes and goes.
Right diagnosis, wrong scope is still a refute of the repair
You can agree with what is wrong and still refute the repair. If the fault is a bad start component but the quote is a full replacement, the diagnosis stands and the proposed repair does not. Say both clearly: the problem is real, the fix is bigger than the problem. That is not trashing anyone; it is right-sizing.
Show the test, not just the verdict
"It is fine" from a stranger is worth as much as "it is bad" from the first shop - two opinions, no evidence. Show the customer the meter, the value against the nameplate, the clean part. Let them watch the winding read or see the amp draw. A second opinion the customer can see is the one they believe and repeat to their neighbors.
When you cannot confirm either way
Sometimes the fault is intermittent or the access does not let you test the claim on this visit. Say exactly that: "I cannot make it fail today, so I can neither confirm nor rule out their call - here is what I would monitor or test to settle it." An honest "I do not know yet, and here is how we would find out" beats a confident guess in either direction.
References
- Trade-standard test methods for compressors, motors, boards, and heat exchangers (generic)
- Manufacturer specifications for nameplate readings and acceptable ranges
- See related: Giving an Honest Second Opinion on Another Shop's Diagnosis; The Other Shop's Diagnosis Is Wrong (decision tree)