Bryant 986TB - Troubleshooting Guide

90
Is AMBER LED status light on?
Is there 24V at SEC-1 and SEC-2? Is there 115V at L1 and L2? Replace furnace control.
Is door switch closed? Replace transformer. Replace door switch. Is there 115V going to switch?
Is door switch closed? Is circuit breaker closed? Check for continuity in wire from circuit breaker to furnace. Close circuit breaker and go back to START.
Is AMBER LED status light blinking rapidly without a pause?
Check for correct line voltage polarity. If units are twinned, check for proper low- voltage (24V) transformer phasing.
Is AMBER LED status light blinking ON/OFF slowly with a combination of short and long ashes? Determine status code. The status code is a 2 digit number with the rst digit determined by the number of short ashes and the second digit by the number o ong ashes?
To recall previous status codes disconnect the R thermostat connection, reset power, and put setup switch SW1-1 in the ON position. The AMBER LED will ash the status codes in the order of occurrence. Record status codes until status code #11 ashes (1 short and 1 long ash). After status code #11 ashes the status codes will repeat. Status codes are erased after 72 hours or can be manually erased by putting setup switch SW1-1 in the ON position and jumpering R, W/W1, and Y/Y2 simultaneously until status code #11 is ashed. When done put setup switch SW1-1 in the OFF position. Was there a previous status code other than #11?
Go to section below for the status code that was ashed.
Does the control respond to W/W1, W2, Y1, Y/Y2, and G (24V) thermostat signals? Run system through a low-heat, high- heat, or cooling cycle to check operation. Status codes are erased after 72 hours or can be manually erased by putting setup switch SW1-1 in the ON position and jumpering R, W/W1, and Y/Y2 simultaneously until status code #11 is ashed.
Is 24V present at W/W1, W2, Y1, Y/Y2 or G thermostat terminals on the furnace control? Check room thermostat or interconnecting cable. Disconnect all the thermostat wires from the furnace control. Does the problem repeat when using a jumper wire?
Replace furnace control.
The thermostat is not compatible with the furnace control. Either install a ballast resistor, connect the Com24V thermostat terminal to the thermostat, or replace the thermostat.
YES NO
YES
YES
YES
YES
YES
SEYSEYSEY
YES
START
YES
YES
NO NO
NO
ONON
NO
ONON
NO
NO
NO
T
roubleshootin
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Guide
A11326A
Fig. 72 − Troubleshooting Guide
986TB