Between Repair Costs and Replacement Value, The $5,000 Furnace Decision Point

https://precisioneverydayhvac.tearosediner.net/neglecting-the-20-percent-rule-exposes-your-hvac-system-to-premature-failure

The $5,000 rule is a repair-cost threshold that guides the repair-versus-replace decision for aging furnaces: if annual repair costs approach or exceed $5,000, or if a single repair tops one-third of replacement cost, replacement often delivers better