Amana GUIA Series Service Instructions Manual page 130

SERVICING
WARNING
To avoid possible fire, only reset the auxiliary limit
control once. If it should open a second time, a quali-
fied servicer must determine why the auxiliary limit
opened before resetting again.
NOTE: If it becomes necessary to slide the blower assem-
bly out of any of the 80% furnaces or the 90% GUCA or
GUSA furnace, the auxiliary limit control must be removed
from the blower deck before the blower assembly can be
removed. After the blower assembly is reinstalled, the aux-
iliary limit must be reinstalled.
To aid in identifying these controls, color coded labels are
attached to the back of the controls. Refer to the Auxiliary
Limit Charts in furnace Technical Manual for color codes
and temperature settings.
S-7 CHECKING FLAME ROLLOUT CONTROL
A temperature activated manual reset control is mounted
to the manifold assembly on 80% & 90% furnaces, as shown
in the following illustrations.
FLAME
ROLLOUT
SWITCH
Flame Rollout Switch Location
(80% Upflow Furnace Shown, Counterflow Similar)
FLAME
ROLLOUT
SWITCHES
* * *
*
2
*
* *
Flame Rollout Switch Location
(90% Upflow Furnace Shown, Counterflow Similar)
130
Rev. 1
The control is designed to open should a flame roll out oc-
cur. An over firing condition or flame impingement on the
heat shield may also cause the control to open. If the rollout
control opens, the air circulation blower and vent blower will
run continuously. On models with the White-Rodgers
50A51, 50M61 and 50V61 or Heatcraft HSI 1-1A ignition
controls the diagnostic light will flash four times. These
symptoms are identical to a trip of the primary limit control.
On models with the White-Rodgers 50A50, 50A55 or
Heatcraft HSI-2 ignition control the diagnostic light will flash
five times indicating a trip of the rollout switch.
To aid in identifying these controls, color coded labels have
been affixed to the back of these controls. Refer to the Rollout
Limit Charts in furnace Technical Manual for temperature
settings and color codes.
If the rollout control has opened the circuit between the igni-
tion control and gas valve will be interrupted.
WARNING
LINE VOLTAGE NOW PRESENT.
1. Remove the burner compartment door to gain access to
the rollout switch(es) mounted to burner bracket.
The servicer should reset the ignition control by opening and
closing the thermostat circuit. Then look for the ignitor glow-
ing which indicates there is power to the ignition control.
Measure the voltage between each side of the rollout control
and ground while the ignition control tries to power the gas
valve.
2. Measure the voltage between each side of the rollout
control and ground during the ignition attempt. Refer to
the following figure.
VOLT / OHM
METER
Checking Flame Rollout Switch
(80% & 90% Furnaces)
a. If no voltage is measured on either side of control it
indicates ignition control or wiring to control problem.
b. If voltage is measured on one side of the control and
not the other it indicates the control is open.
RED
RESET
BUTTON
COLOR
IDENTIFYING
TAB