Page 24
NO
NO
NO
YES
YES
G25MV VSM BLOWER AND VSP2–1 BLOWER CONTROL BOARD
TROUBLESHOOTING FLOW CHART
DOES UNIT OPERATE?
CHECK:
1–UNIT POWER
2–INTERLOCK SWITCH
3–TRANSFORMER
4–LIMIT SWITCH
REPLACE VSP2–1.
END OF COOLING TEST
CHECK UNIT WIRING
AND IF CORRECT
REPLACE THE
VSP2–1.
COOLING MODE
NO
YES
YES
YES
IS BLOWER ON HIGH SPEED AND ARE DS1 AND
DS3 LIT? DOES THE “CFM” LED–DS4 LIGHT BLINK
ONCE FOR EVERY 100 CFM SELECTED IN THE
TABLES ON PAGE 2?
IN ADDITION TO R AND
G, JUMPER R AND DS.
IS 24 VOLTS PRESENT AT
TERMINAL “VSP2 #12” ON
BURNER CONTROL BOARD?
IS BLOWER ON LOW SPEED AND IS
“ON/OFF” LED–DS3 LIT? “CFM” LED–
DS4 LIGHT SHOULD BLINK ONCE FOR
EVERY 100 CFM SELECTED IN THE
TABLES ON PAGE 2.
CHECK UNIT WIR-
ING AND IF COR-
RECT, REPLACE
VSP2–1.
PLACE JUMPER ACROSS R AND G.
IS 24VAC ACROSS
R AND C?
NO
NO
YES
YES
DOES UNIT OPERATE?
CHECK:
1–UNIT POWER
2–INTERLOCK SWITCH
3–TRANSFORMER
4–LIMIT SWITCH
END OF TEST
REPLACE THE VSP2–1.
HEATING MODE
NO
YES
YES
YES
AFTER THE SELECTED
TIME, DOES BLOWER
TURN OFF?
PLACE “HTG. BLOWER”
JUMPER IN POSITION #1.
R AND W1 REMAIN JUMPERED.
1–CHECK UNIT WIRING AND IF
CORRECT, REPLACE VSP2–1.
PLACE “HTG. BLOWER” JUMPER IN POSITION #2.
PLACE JUMPER ACROSS R AND W1. WAIT 75
SECOND FOR PREPURGE AND FAN“ON” DELAY.
IS 24VAC ACROSS
R AND C?
2–BREAK AND REMAKE JUMPER
(R TO W1).
3–AFTER 30–35 SECOND
PURGE, IS 24VAC PRESENT
AT GAS VALVE?
REPLACE VSP2–1.
REMOVE JUMPERS
YES
NO
CHECK UNIT WIRING
AND IF CORRECT,
REPLACE VSP2–1.
NO
IS BLOWER ON LOW SPEED AND IS “ON/OFF” LED–
DS3 LIT? “CFM” LED–DS4 LIGHT SHOULD BLINK
ONCE FOR EVERY 100 CFM SELECTED IN THE
TABLES ON PAGE 2.
DOES BLOWER SHIFT TO HEAT SPEED
AND IS “HEAT” LED–DS2 ON? DOES
THE “CFM” LED–DS4 LIGHT BLINK
ONCE FOR EVERY 100 CFM SELECTED
IN THE TABLES ON PAGE 2?
NO
IS 24 VOLTS PRESENT AT
TERMINAL “VSP2 #12” ON
BURNER CONTROL BOARD?