HVAC Troubleshooting
HVAC Troubleshooting Guide
Residential & Commercial — Checks you can safely do before calling a technician
Gas Odor or Carbon Monoxide — Act First
Gas odor
Do not operate any switches, thermostats, or electrical devices. Do not use your phone inside the building. Leave the area immediately, leaving doors open as you go. Once outside and away from the building, call 911 and your gas utility's emergency line. Do not re-enter until emergency services clear the building.
Carbon monoxide alarm
Evacuate everyone immediately. Do not stop to investigate. Call 911 from outside. Do not re-enter until emergency services confirm it is safe. Carbon monoxide is odorless and colorless — take every alarm seriously.
These guides cover the most common HVAC symptoms. Each check is within normal owner operation — thermostat settings, accessible filters, visible conditions, and control displays. Do not open electrical panels, access rooftop units, or work near moving fan blades. If you are unsure whether a check is safe, skip it and call us.
Select a Symptom
Official Manufacturer Resources
Owner manuals contain model-specific filter sizes, error code lists, and reset procedures for your exact HVAC system. Always use the manual for your exact model number.
Owner manuals contain model-specific filter sizes, cleaning schedules, error code lists, and reset procedures. Always use the manual for your exact model — procedures vary significantly between models even from the same manufacturer.
Need a Technician?
These guides cover owner-level checks. When you're ready for professional service — or if any check tells you to stop — call us or submit a service request.