Goodman · Air conditioner

CoreSense 1 Yellow 1 flash - long run time (low side)

Medium severity Goodman/Amana R-32 GLXS/ALXSGoodman/Amana R-410A GSX/ASX/DSX (ANX/SSX/VSX)

What the control is telling you

Compressor has run more than 18 hours straight, showing low capacity from a low-side problem. This code is disabled in heat pump heating mode.

Applies to: Copeland CoreSense 3-wire module: Amana/Deluxe R-410A ASX, ASZ, DSX, DSZ units and Amana R-32 ALXS / ALZS units

Likely causes

Low charge
Indoor blower not running (relay, capacitor, motor, wiring, indoor board, open thermostat wire)
Frozen evaporator (low suction, low set point, blocked coil/filter/ducts)
Metering device stuck or TXV bulb badly mounted
Restricted liquid line drier
Thermostat short or poor location

Test and repair steps

Check charge and look for leaks.
Verify the indoor blower and its control; clean filter and coil, open registers.
Check TXV bulb size, location and contact; check for a stuck TXV or piston.
Check the drier for a temperature drop.
Check thermostat sub-base, wiring and location.

Models that show this code

150 models in Goodman/Amana R-32 GLXS/ALXS, Goodman/Amana R-410A GSX/ASX/DSX (ANX/SSX/VSX)

ALXS3BN**10AAALXS4BA**10AAALXS4NA**10AAALXS5BA**10AAANX130181ANX130241ANX130301ANX130361ANX130421ANX130481ANX130601ANX130611ANX140181ANX140191ANX140241ANX140251ANX140301ANX140361ANX140371ANX140421ANX140431ANX140481ANX140601ASX130181ASX130241ASX130301ASX130361ASX130421ASX130481ASX130601ASX130611ASX140181ASX140191ASX140241ASX140251ASX140301ASX140311ASX140361ASX140371ASX140421ASX140431ASX140481ASX140601ASX160181ASX160241ASX160301ASX160311ASX160361ASX160371ASX160421ASX160481ASX160601ASX160611ASX180**1ABASXH5***10DSX160241DSX160361GLXS3BN**10AAGLXS4BA**10AAGLXS4MA**10AA

Other codes on the same units

Comfort Alert 7 Yellow ALERT 7 flashes - open run circuit
Comfort Alert 9 Yellow ALERT 9 flashes - low control voltage
Comfort Alert TRIP Red TRIP LED - call present but compressor not running
Comfort Alert TRIP+ALERT TRIP and ALERT LEDs flashing together - control voltage too low
CoreSense 2 Pressure trip - yellow 2 flashes (red 2 = lockout)
CoreSense 3 Short cycling / pressure switch cycling - yellow 3 (red 3 = lockout)
CoreSense 4 Locked rotor - yellow 4 (red 4 = lockout)
CoreSense 5 Moderate run trip - yellow 5 (red 5 = lockout)

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Source: Goodman RS6200301 R-32 GLXS/ALXS/GLZS/ALZS service (07-2024), CoreSense Diagnostics Table p.21-22 and Quick Reference Table p.23; Goodman RS6200006r103 R-410A ASX/GSX/DSX/ASZ/GSZ/DSZ service (text export) (Goodman_R_410A_ASX_GSX_DSX_A_C_and_ASZ_GSZ_DSZ_HP_covers_GSX_GSZ_lines_GSXH5_GSZH5_service.txt section Diagnostics Table: Coresense Module / Table 1 Quick Reference). Summarized in our own words; check the original manual for your model.

Homeowner looking at this code? See what it means for you and when to call a technician.

For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.