Service manual

SERVICING
45
3. Reset the roll-out control.
4. Turn power on and put the unit into a call for heating.
CAUTION
Assume flame roll-out could occur. Keep face and
hands a safe distance from burner area.
5. Look under the heat shield as the unit is running.
Flames should be drawn into firing tubes.
A. If only one burners flame is not drawn into the
tube, that tube is restricted.
B. If with out the air circulation blower running, all
flames are not drawn into the tubes either the
collector box, combustion blower, or flue outlet is
obstructed. If the combustion blower or flue out-
let is obstructed, the pressure switch should have
opened preventing the unit from firing, also in-
spect the unit pressure switch and wiring.
C. If the burner flame is not drawn into the tube only
when the air circulation blower is running, then a
cracked heat exchanger tube is present.
S-304 TESTING GAS VALVE
Smart Valve Systems
Amana package units utilize Honeywell "Smart Valve" gas
valves which provides all manual and automatic control func-
tions required for gas fired heating equipment.
C
X
C
NEUTRAL
1
2
SS
H
E
A
T
C
O
O
L
Y
1
2
34
S
3
MOTOR
LEADS
UNUSED
C G Y W R
HEAT FAN
DELAY
OFF
90
60
120
150
XFMR SEC
SMART VALVE FAN TIMER BOARD
NORMAL SEQUENCE OF OPERATION
1. Thermostat calls for heat. The combustion blower is im-
mediately energized.
2. The pressure switch contacts transfer.
3. The ignitor is energized and pilot gas begins to flow.
4. After pilot flame is proven, the main valve is energized
and the pilot will light the main burners.
5. The control checks the signal from the flame sensor. Gas
flow will continue only if a proper signal is present. As
soon as pilot flame is proven, the ignitor is de-energized.
6. The unit will continue to fire for 30 seconds. The fan con-
trol will then start the main circulating air blower.
7. The unit will deliver heat to the conditioned space until
the thermostat is satisfied.
8. The gas valve and combustion blower will be de-ener-
gized when the thermostat opens.
9. There is an adjustable Heat Fan OFF of approximately
60/90/120/150 second delay (factory set at 120). The
control module (figure 6) will de-energize the blower
once the selected time has elapsed. This allows any
additional heat in the heat exchanger to be transferred
to the conditioned space.
RESET AFTER CONTROL LOCKOUT
Amana PGA__C, PGB__C and PGD__C units built prior to
July, 1999, are equipped with the Honeywell "Smart Valve"
system. If the control senses a loss of flame, the control will
automatically attempt to relight. A lockout occurs only when
the ignitor fails, roll-out switch, primary limit or secondary
limit opens. This causes the air circulation blower to run
continuously, and ignition is no longer attempted. When
this occurs, it may be necessary to reset the control by turn-
ing the thermostat setting below room temperature for sev-
eral seconds and then returning the setting to the desired
temperature. The roll-out and secondary limit are manual
reset switches and require resetting before normal opera-
tion can continue. A failed ignitor will require replacement.
The control may also be reset after a lockout by turning off
the electrical disconnect switch to the furnace for several
seconds.
IMPORTANT: If the furnace frequently has to be reset, it
means that a problem exists that should be corrected.
WARNING
Disconnect Electrical Power Supply:
1. Remove wire connections from gas valve terminals.
2. Using an ohmmeter, test across the ignitor terminals,
(Terminals 1 & 2 on the Q3450 harness)
3. Should read continuity, if not replace ignitor.
4. Using an ohmmeter, test from flame sensor to ground
on the Q3450 harness.
6. If continuity is shown, replace pilot assembly.
7. Reconnect harness(es) to gas valve.
8. Restore power to unit.
WARNING
Voltage Now Present
9. Set thermostat to demand for heat.