Bryant 350MAV user manual Troubleshooting Guide, Start, A02204a

Models: 350MAV

1 16
Download 16 pages 59.74 Kb
Page 14
Image 14
—14—

—14—

START

Is LED status light on?

YES

Is LED status light blinking rapidly without a pause?

NO

Is LED status light blinking ON/OFF slowly with a combination of short and long flashes?

YES

Determine status code. The status code is a 2 digit number with the first digit determined by the number of short flashes and the second digit by the number of long flashes?

TROUBLESHOOTING GUIDE

NO

 

 

 

NO

 

Is there 115V at L1 and L2?

 

 

 

Is door switch closed?

 

 

 

 

 

YES

 

 

 

 

 

YES

 

 

 

 

 

 

 

 

 

 

 

NO

 

 

 

 

 

 

 

 

Is there 24V at SEC-1 and SEC-2?

 

 

 

 

Is there 115V going to switch?

 

 

 

 

 

 

YES

 

 

 

 

 

YES

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Replace furnace control.

 

 

 

Replace door switch.

YES

Check for correct line voltage polarity. If units

 

 

 

Replace transformer.

 

 

 

 

are twinned, check for proper low-voltage

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(24V) transformer phasing.

 

 

 

 

 

 

NO

To recall status code briefly remove and reconnect one RED wire from the Limit

 

Switch or Flame Rollout switch to display stored status code. On RED LED

 

 

control do not remove power or blower access panel before initiating status

 

code recall. You can also recall the previous status code by momentarily shorting

 

the TEST/TWIN terminal to Com24V terminal until the LED goes out. LED will

 

flash the previous status code or status code #11 (1 short and 1 long flash) if

there was no previous code. After the control repeats the code 4 times, the control will go through a brief component test sequence. The inducer will start and run for the entire component test. The HSI, blower motor FAN speed (AMBER LED boards only) HEAT speed, and COOL speed will run for 10 – 15 seconds each. Gas valve and humidifier will not be turned on.

NO

Close door switch and go back to START.

NO

Is circuit breaker closed?

YES

NO

Check for continuity in wire from circuit breaker to furnace.

Close circuit breaker and go back to START. START

Check room thermostat or

interconnecting cable.

NO

Go to section below for the status code that

YES

Was there a previous status code

NO

Does the control respond to W, Y1 (if present),

 

was flashed.

 

other than #11?

 

Y/Y2, and G (24V) thermostat signals?

 

 

 

 

 

YES

 

 

 

 

 

 

 

 

 

 

 

Run system through a heating or cooling cycle to check operation. Status codes are erased after 72 hours. On RED LED boards stored status codes can also be erased whenever (115V or 24V) is interrupted.

Replace furnace control.

NO

Is 24V present at W, Y1 (if present), Y/Y2 or

 

G thermostat terminals on the furnace control?

YES

Disconnect all the thermostat wires from the furnace control.

YES

Does the problem repeat when using

 

a jumper wire?

 

 

NO

 

 

 

 

 

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.

A02204a

Page 14
Image 14
Bryant 350MAV user manual Troubleshooting Guide, Start, A02204a