01
3 flashes · Trane
- Display
- Integrated furnace control error flash code
- Equipment
- Gas-fired, direct-vent condensing furnace
- Applicable models
- *UH1 and *DH1 furnace models covered by the cited Trane guide
What the manufacturer reports
Trane labels 3 flashes a draft pressure error. The guide lists a venting problem, a pressure-switch problem, or an inducer problem as possible explanations.
What that means for a homeowner
The furnace control is reporting that its draft or venting safety check has a problem. The flash pattern does not tell you which condition is present or identify a failed part.
What to do next
Contact an HVAC technician promptly and share the model number and flash count. Do not open the furnace, inspect venting, or test switches, wiring, or controls.
Manufacturer documentation: Trane: Installer’s Guide for *UH1 and *DH1 Furnaces (18-CD29D1-14-EN). Table 21 lists the integrated furnace control flash codes, including 3 flashes for a draft pressure error and possible venting, pressure-switch, or inducer problems.
02
8 red LED flashes · Amana
- Display
- Red diagnostic LED on the unit control
- Equipment
- R-32 packaged gas/electric HVAC unit
- Applicable models
- APGM3 line; the cited wiring diagram is for APGM360***31
What the manufacturer reports
Amana’s red diagnostic LED table for the cited wiring diagram labels 8 flashes as ignition lockout.
What that means for a homeowner
The unit control is reporting an ignition lockout. This code does not establish the cause or show that a particular component needs replacement.
What to do next
Arrange HVAC service promptly, especially if heat is unavailable or the code returns. Share the exact model and LED color/count. Do not repeatedly reset the unit, open its cabinet, check gas or electrical parts, or replace components.
Manufacturer documentation: Amana: APGM3 R-32 Packaged Gas/Electric Units — Specifications and Wiring Diagrams. The product document identifies the APGM3 gas/electric packaged-unit line and includes a wiring diagram for APGM360***31; its red diagnostic LED table lists 8 flashes as ignition lockout.
03
Start with the exact model and manual
Code meanings and display sequences vary by manufacturer, equipment type, model, control, and product revision. A number or flash pattern can mean something different on another system. Check the owner’s manual for your exact equipment and revision, or ask an HVAC technician to identify the right manual. A code reports a condition the control detected; it is not a diagnosis by itself.
04
Record what you can see without opening equipment
From the thermostat or a display you can safely see, note the code exactly, including letters, LED color, and flash count. Write down when it appeared and what the system was doing. If the model number is already in your paperwork or visible on an exterior label, record it too. Do not remove a panel or reach inside to find a light or label.
05
Limits and urgent help
These are examples tied only to the named manufacturer documents and product families, not a universal HVAC code chart. Controls and manuals can change across model and product revisions. Use the manual for your exact equipment and let a qualified HVAC technician diagnose the cause. Do not open equipment, perform electrical tests, bypass a safety device, handle refrigerant, or replace a component based on a code.
Read the Urgent HVAC Warning Signs guide for steps to take for gas odors, carbon monoxide alarms, smoke, electrical hazards, and other warning signs.