You're assigned to fix a non-operational controller but there's no program loaded, no documentation, and the integrator who built it is unavailable. How do you proceed?
Solution
1. Determine If Controller Ever Had Valid Programming
Connect to the controller and check if a program exists (should show in memory)
If empty or corrupted, you can't proceed without base program
2. If No Program Loaded
Escalate immediately to project manager or contractor who installed the system
This is NOT a service tech problem—this is a scope issue
Request the baseline/original program file from the integrator
Demand they either provide it or come on-site to load it
3. If Program Exists but Broken
Attempt diagnosis:
Does controller power up?
Does it respond to network pings/BACnet discovery?
Are any basic functions working (lights, fans, compressor)?
Log your findings and submit to integrator with request for root cause analysis
4. If You Have Company Archives
Search for similar equipment from previous jobs
Use prior programs as a template (if architecture is similar)
DO NOT deploy without testing—verify all I/O first
5. Advocating for Realistic Expectations
Document the hours spent on troubleshooting vs. actual work
Push back on PM/sales: "This can't be preventive maintenance if there's no baseline"
Propose solutions:
Require full documentation for every controls handoff
Schedule programming review before customer acceptance
Build buffer time for integration issues into quotes
6. Creating a Preventive Maintenance Program
If you take over support, create a documented baseline for each system
Monthly or quarterly checks: verify program is intact, backup current config
Log any parameter changes so next tech knows the history