Service Manual Manual

Page 22
LAARS Heating Systems
YES
CHECKING INTERNAL PUMP
(YOU MUST COMPLETE PAGE 16 FIRST)
SWITCH POWER ON, GREEN
POWER LIGHT LIGHTS
CALL FOR HEAT EXISTS
(THERE IS 24 VOLTS ON
PINS #7 & #9 ON
'CONTROL' PLUG - CN6)
THERE IS 120 VAC AT
'CIRCULATOR' PLUG-CN5
TURN UP T'STAT OR AQUASTAT OR
CORRECT STAT PROBLEM
NO
YES
NO
YES
SEE TROUBLE SHOOTING
CHART PAGE 16
THERE IS 120 VAC AT PUMP
REPLACE BOILER
CONTROL P/N 2400-224
NO
CORRECT WIRING BETWEEN
PUMP AND CONTROL BOX
NO
MOTOR PUMP RUNS
YES
NO
REPLACE PUMP
PUMP IS PUMPING
YES
PUMP OK
PUMP IS AIR BOUND OR IMPELLER HAS
BROKEN; ELIMINATE AIR OR REPLACE PUMP
NO
YES