The $5000 Emergency Threshold Separates Immediate Repair from Total System Replacement
https://precisionhvacnearuc-davis.yousher.com/most-hvac-systems-reach-30-years-through-planned-repair-investment-and-diagnostic-pricing
The $5000 rule for HVAC is a critical emergency go-no-go threshold: if repair costs reach or exceed half your system's remaining useful life value, immediate intervention becomes a safety and financial decision point