Confirm the problem and the load

A failed component does not prove the whole system must be replaced, and the old nameplate does not prove the same capacity is still correct.

Document comfort complaints, repair history and any envelope changes before contractors size a replacement.

Compare complete installed scope

Require exact indoor and outdoor model numbers, the matched-system reference, duct findings, condensate work, electrical scope, permits and disposal.

A low quote may exclude duct sealing, platform work, line-set decisions, thermostat changes or permit fees.

Require startup evidence

Commissioning should verify airflow, refrigerant charge using the manufacturer procedure, electrical operation, drainage and controls.

Keep registration, parts warranty and labor warranty terms separate so the coverage can be compared accurately.

Publication record

How this guide was produced

CoolCompare Editorial reviewed 2 linked evidence sources and separated source facts from homeowner checks, calculations and limitations. This page does not claim hands-on product testing, professional inspection or address-specific verification unless the article explicitly documents it.

Reviewed 5 August 2026. See the editorial policy, fact-checking standard and corrections process.

Sources and further reading

Questions or corrections? Contact the editorial team.