Service Manual Manual

Page 20
LAARS Heating Systems
WITH A CALL FOR HEAT RESET
BOILER CONTROL BY SWITCHING
OFF BOILER SWITCH FOR 15 SECS.
AFTER TWO SECONDS GREEN
POWER LIGHT COMES ON.
REFER TO GENERAL TROUBLE
SHOOTING SECTION PAGE 16
CONNECT MANOMETER TO "PRESSURE TAP" ON
GAS VALVE - PRESSURE DURING BLOWER
OPERATION WITHOUT GASFLOW (VALVE/FLAME
LIGHT NOT LIT) IS - 4 IN. W.C.
CHECK FOR VOLTAGE 120 VAC
AT BLOWER WIRE CONNECTOR
(WITHIN 5 MINS. AFTER GREEN
LIGHT)
BLOWER O.K.
REPLACE BLOWER
BLOWER STARTS
YES
YES
NO
YES
NO
NO
CHECKING BLOWER
(YOU MUST COMPLETE PAGE 16 FIRST)
REPLACE BLOWER
0 VOLTS
120 VAC
CHECK TT, LIMITS,
STACK SWITCH
REPLACE BOILER
CONTROL 2400-224
REFER TO PAGE 17
REFER TO PAGE 19
OK
OPEN