Rx LED off Green receive LED off - no power or communications error

What the control is telling you

The green Rx LED is dark: either the furnace has no power or there is a communications error.

Applies to: GMVC95/AMVC95 upflow and *CVC9 counterflow two-stage furnaces

Likely causes

• No power to the furnace
• Open fuse
• Short in low voltage wiring
• Communications error

Test and repair steps

1. Safety turn power off before working on the control or wiring.
2. Check breakers and the 3 A control fuse. Replace a blown fuse with the same type.
3. Look for shorts in the furnace and system low voltage wiring.
4. Press the learn button to reset the network.
5. Check the data 1 / data 2 voltages (see the ComfortNet data line guide).

Settings for these units

• Normal status displays (7-segment) · Goodman/Amana GM9S96/AM9S96
• Normal status displays (7-segment) · Goodman/Amana GM9S80/AM9S80
• Normal status displays (7-segment) · Goodman/Amana GM9C96/AM9C96
• Minimum recommended filter size · Goodman/Amana GM9C96/AM9C96

Models that show this code

10 models in Goodman/Amana *MVC95/*CVC9 two-stage ComfortNet

Other codes on the same units

• HI High-stage heat
• OP Normal - waiting for a call
• Red LED 1 flash Red communications LED 1 flash - communication failure
• Red LED 2 flashes Red communications LED 2 flashes - reset in progress
• Red LED off Red communications LED off - normal
• Rx LED 1 steady flash Green receive LED single steady flash - no network found
• Rx LED on solid Green receive LED on solid - data lines miswired or shorted
• Rx LED rapid flash Green receive LED rapid flashing - normal network traffic