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

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

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

Models that show this code

122 models in Goodman/Amana R-32 GLZS/ALZS, Goodman/Amana R-410A GSZ/ASZ/DSZ (ANZ/SSZ/VSZ)

Other codes on the same units

• 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)
• CoreSense 9 Red 9 flashes - PROT output overcurrent
• CoreSense solid red Solid red TRIP - call present but compressor not running