14
CONDITION “E” continued…
2.
If measured fan pressure is at or below the minimum for Fan Prove Switch (PS2) operation.
POSSIBLE CAUSE
VERIFICATION
SOLUTION
Fan Motor
Turn Rocker Switch and Gas Valve
If you read 115V, proceed with
top knob OFF. Remove air cushion
verification.
cover. (On AM-100 & -150 lift fan
assembly out of boiler and check
If no voltage, check for open circuit
motor is securely fastened to the
(see below).
mounting plate). Disconnect the fan
motor wire leads from the boiler
wiring at quick connects provided.
Turn the Rocker Switch ON. With a
voltmeter, check for 115V across the
supply leads from the boiler.
Turn Rocker Switch OFF. Reconnect
If the motor runs, proceed with check.
fan leads to motor. (For AM-100 &
-150, place fan assembly on ledge
If motor does not run, replace motor
of air cushion chamber). Turn
fan assembly.
Rocker Switch ON.
AM-300 Blower Wheel -
Turn Rocker Switch OFF. Remove
If loose, secure blower wheel
Obstructed or loose
fan from mounting studs and check
properly on shaft. If obstructed
blower wheel is secure on shaft, not
remove obstructions.
rubbing against housing and free
from obstruction.
If ok, proceed with verification.
AM-300 Blocked Air Inlet
Check for obstructions in air supply
If obstructed, remove obstruction.
Orifice
vent terminal and piping. On AM-300
check inlet orifice located in inlet
If unrestricted, proceed with
adapter: see FIG. 7.
verification.
AM-100 and 150
Check that impeller is firmly secured
If broken replace impeller and/or
Broken Impeller
to motor shaft.
assembly.
Air Inlet Vent and Lines
Check air inlet terminal for blockage
If obstructed - clear vent inlet.
from freezing or debris.
If clear, proceed with vent line check.
Check vent lines for sagging low
spots which can act as water
If sagging is observed, support
trap and reduce the air supply.
pipe to remove “traps.”
Open Fan Circuit
Remove the three conductor Molex
If no continuity, replace GC-4
GC-4A Control Checkout
connector (with red and black wires)
ignition control following instructions
from GC-4 ignition control.
packaged with replacement.
CAUTION: 115 VAC supply. Turn
If continuity is ok - check wiring.
Rocker Switch OFF and then ON.
Within 30 sec. check for continuity
across the two outer Molex connector
sockets on the ignition control
(Term. 1 & 3).
