Bryant 355AAV EVOLUTION, Troubleshooting Manual

Page 1: ...l should install repair or service heating equipment Untrained personnel can perform basic maintenance functions such as cleaning coils or cleaning and replacing filters All other operations should be...

Page 2: ...e furnace for single stage cooling and heat pumps Y1 Y Y2 and G are required for two stage cooling and heat pumps G is required for continuous fan COM 24V is required for some clock thermostats These...

Page 3: ...ore Trials For Ignition before going to Ignition Lockout Lockout will be reset automatically after three hours by momentarily interrupting 115 vac power to the furnace or by interrupting 24 vac power...

Page 4: ...flow is based on the A C selection shown in Table 1 The electronic air cleaner terminal EAC 1 is energized with 115 vac when the blower motor BLWM is operating When the thermostat is satisfied the R t...

Page 5: ...ersed The DHUM input is turned ON when no dehumidify demand exists Once 24 vac is detected by the furnace control on the DHUM input the furnace control operates in Thermidistat mode If the DHUM input...

Page 6: ...hanges the timing sequence to avoid long blower off times during demand defrost cycles Whenever W W1 is energized along with Y1 or Y Y2 the furnace control CPU will transition to or bring on the blowe...

Page 7: ...ROVING SIGNAL Flame is proved while gas valve is de energized Inducer will run until fault is cleared Check for Leaky gas valve Stuck open gas valve 23 PRESSURE SWITCH DID NOT OPEN Check for Obstructe...

Page 8: ...of operation or the inducer RPM signal was lost for 5 seconds during operation Check for Proper vent sizing Restricted combustion air supply Failed inducer motor Improper motor wiring 43 LOW HEAT PRE...

Page 9: ...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 flashed 9 10 9 Go to page numb...

Page 10: ...dly in only one of the twinned units 9 16 9 Are the fuses breakers or manual disconnects to the problem unit correctly set 11 10 10 Fix problem 5 11 Are the Auxiliary Limit switches properly set 12 10...

Page 11: ...eplace the variable speed furnace control 7 13 Reconnect the G thermostat lead or jumper and observe operation of furnace in cooling mode for 10 minutes 14 14 Does the furnace operate properly in cool...

Page 12: ...re 6 6 Is the high heat rate approximately the same as the low heat rate 7 11 7 Do you have 24 vac across gas valve terminals HI and COM 24V on 2 stage gas valve during high heat 10 8 8 You have an op...

Page 13: ...P AND STARTUP INSTRUCTIONS INDEX 5 Is setup switch SW1 6 in the ON position 6 7 6 Put setup switch SW1 6 in the OFF position 4 7 Jiggle setup switches SW1 1 and SW1 6 back and forth If status code 11...

Page 14: ...nace was probably interrupted or line voltage was too low during a call for heat This is normal operation Go to the page number indicated in Index for the CLEANUP AND STARTUP INSTRUCTIONS INDEX Status...

Page 15: ...e 14 IGNITION LOCKOUT This status code indicates the furnace failed to ignite gas and or prove flame in 4 attempts The variable speed furnace control will auto reset in 3 hours If the inducer motor is...

Page 16: ...4 Disconnect wire from the flame proving sensor electrode FSE 8 5 Does status code 22 stop flashing 6 7 6 Clean flame sensor with fine steel wool Inspect burner box assembly and remove any carbon depo...

Page 17: ...n power off and disconnect PL1 from variable speed furnace control 9 9 Do you have continuity between either RED wire connected to the limit circuit and chassis ground 10 3 10 You have a short circuit...

Page 18: ...re switch HPS and gas valve GV is shorting to ground Replace or repair it 11 45 Disconnect jumper wire across R W W1 and W2 thermostat terminals and wait until blower stops 46 46 Jumper R G and Y Y2 t...

Page 19: ...wiring schematic for the correct part number If absolutely necessary you can install two resistors into the PL4 connection on the control board R1 goes across the middle 2 pins and R2 goes across the...

Page 20: ...variable speed will stop displaying status code 31 STEP ACTION YES NO GO TO 1 Turn power off remove blower access panel and disconnect User Interface ABCD connector if used or the R thermostat lead if...

Page 21: ...e switch HPS 12 Status Code 32 LOW HEAT PRESSURE SWITCH DID NOT CLOSE OR REOPENED This status code can occur as a result of the low heat pressure switch LPS not making or the low gas pressure switch L...

Page 22: ...across heat exchangers when fault occurs 25 26 25 Replace the pressure switch assembly 8 26 Is inducer motor rotating in direction indicated on the inducer housing 28 27 27 Replace inducer motor or i...

Page 23: ...n power off 15 15 Do you have continuity across limit switch LS 19 16 16 Wait for unit to cool then recheck for continuity across limit switch LS 17 17 Do you have continuity across limit switch LS 19...

Page 24: ...elow 210 deg F 18 56 56 The problem may be related to poor air distribution or excessive pressure drop across filter Check filter and return air grilles for blockage Add turning vanes more supply open...

Page 25: ...and igniter Replace failed component 15 15 Fix problem 8 16 Put setup switch SW1 6 in the OFF position and jumper the R and W W1 thermostat terminals 17 17 Is 24 vac across BLUE and GREEN YELLOW wire...

Page 26: ...fter the gas valve is energized Flame sensor location Air leakage around igniter bracket 8 48 Furnace will not operate or ignite on low heat Check the following Flame sensor location Very low manifold...

Page 27: ...Note The voltage should be very stable and should not fluctuate more than 02 vdc If the voltage fluctuates get a different volt meter before going on to the following steps Note Since the variable sp...

Page 28: ...ortion of blower motor DO NOT PULL ON WIRES GRIP PLUG ONLY 42 42 When blower control module is completely detached from blower motor verify with standard ohmmeter that the resistance from each motor l...

Page 29: ...29 29 Disconnect collector box tube to pressure switch assembly 30 30 Turn power on and jumper the R and W W1 thermostat terminals 31 31 Does status code 42 flash within 20 seconds after a call for he...

Page 30: ...s 45 49 Status Code 43 LOW HEAT PRESSURE SWITCH OPEN WHILE HIGH HEAT PRESSURE SWITCH IS CLOSED This status code can occur as a result of the low heat pressure switch LPS not making during a call for h...

Page 31: ...Replace the low heat pressure switch or the pressure switch assembly 8 Status Code 45 CONTROL CIRCUITRY LOCKOUT This status code indicates the variable speed furnace control detected one of the follow...

Page 32: ...MAIN HARNESS CONNECTOR PL3 ECM BLOWER HARNESS CONNECTOR TRANSFORMER 24 VAC CONNECTIONS 3 AMP FUSE STATUS AND COMM LED LIGHTS SW1 SETUP SWITCHES AND BLOWER OFF DELAY MODEL PLUG CONNECTOR AIR CONDITION...

Page 33: ...33 Fig 2 Schematic for 355MAV and 355AAV with ECM 2 5 Blower Motor...

Page 34: ...34 Fig 3 Schematic for 355AAV with ECM 3 0 Blower Motor...

Page 35: ...35 Fig 4 Schematic for 355BAV with ECM 2 5 Blower Motor...

Page 36: ...tor then delivers requested airflow CFM as defined by serial commands received from the variable speed furnace control The ECM blower motor is configured via the variable speed furnace control to reac...

Page 37: ...0 000 80 000 100 000 120 000 1 81 in wc max 1 63 in wc 0 05 0 95 in wc max 0 80 in wc 0 05 355BAV PRESSURE SWITCH MAKE BREAK POINTS HIGH HEAT PRESSURE SWITCH LOW HEAT PRESSURE SWITCH UNIT SIZE BTUH Ma...

Page 38: ...38 APPENDIX D STATIC PRESSURE READING LOCATION DIAGRAMS Figure 7 Upflow Total Static Pressure Reading Locations Figure 8 Downflow Total Static Pressure Reading Locations...

Page 39: ...Coil 0 20 in w c Coil Static Pressure Drop Wet 0 20 in w c Total ESP 0 60 in w c Both Examples 1 and 2 are correct Example 1 ESP readings were taken as laid out in static pressure reading location di...

Page 40: ...ew HSI resistance over time 355AAV 355BAV Ohm reading of HSI 70 F 40 to 70 ohms resistance will remain relatively stable over the life of the igniter The Silicon Nitride igniter in this furnace is not...

Page 41: ...rnace will do on a cold start coming out of night setback coming on in low heat and coming on in high heat EXAMPLE 1 Furnace ran for 16 minutes in low heat and 5 minutes in high heat during previous c...

Page 42: ...42 A02281...

Page 43: ...oduct theory and skills programs is available using popular video based formats and materials All include video and or slides plus companion book Classroom Service Training plus hands on the products...

Page 44: ...44 Replaces SM05 5 Form SM05 07 6 08...