Amana GUCA045AX30 Service Instructions Manual page 72

a. If no voltage is measured on either side of control it
indicates that either the ignition control or wiring to
control is the problem.
b. If voltage is measured on one side of the control and
not the other it indicates the control is open.
c. If voltage is measured on both sides of the control
the wiring to gas valve or valve is at fault.
3. After check and/or replacement of rollout switch, rein-
stall burner compartment door and verify proper unit
operation.
S-23 HEAT EXCHANGER ASSEMBLY
With the improvements in the product design of these model
furnaces, the Heat Exchanger Assembly, primary and sec-
ondary, can now be replaced as a single unit thus eliminat-
ing the need to replace the furnace due to defect in either
material or workmanship.
The service replacement heat exchanger assemblies con-
tain the complete heat exchanger assembly, primary and
secondary, along with three pieces of gasket material that
are used between the heat exchanger assembly and the
inside rails. There are a total of twelve Heat Exchanger
Replacement Kits available for these model furnaces, six
for the GUCA models and six for the GCCA models.
The following chart lists the kit number and the model fur-
nace that it is used on.
R Kit #
R9800656
R9800657
R9800658
R9800659
R9800660
R9800661
R9800662
R9800663
R9800664
R9800665
R9800666
R9800667
Note: The following is a brief explanation of the heat ex-
changer removal and replacement procedures. For com-
plete detailed instructions on the heat exchanger removal
and replacement procedures, refer to the installations in-
structions provided with the Heat Exchanger Replacement
Kits listed in the above chart.
72
Rev. 0
SERVICING
Used on Models
GUCA045AX30
GUCA070AX30
GUCA070AX40
GUCA090AX40
GUCA090AX50
GUCA115AX50
GCCA045AX30
GCCA070AX30
GCCA070AX40
GCCA090AX40
GCCA090AX50
GCCA115AX50
Removal of Existing Heat Exchanger:
WARNING
Disconnect Electrical Power and Shut Off Gas Supply:
Note: Save all components (except existing heat ex-
changer) and screws removed in the following procedures
for reassembly.
1. After electrical power and gas supply have been shut
off, remove the burner and blower compartment doors.
2. Remove the gas supply piping from the unit. In order to
have proper clearance to remove the heat exchanger
assembly, all gas piping needs to be removed from the
inner cabinet of the furnace.
3. Disconnect the attached supply ductwork along with the
combustion air pipe (Direct Vent Only) and vent/flue pipe
from the furnace.
Note: The GCCA model furnace installed in counterflow
position will need to be removed from the installation in
order to gain access to the screws that attach the top cover
assembly to the furnace. To remove the GCCA model fur-
nace, disconnect both the supply and return ductwork con-
nections and the incoming electrical power lines along with
the combustion air pipe (Direct Vent Only) and vent/flue
pipe from the furnace.
4. Disconnect and remove the condensate drain lines and
drain trap.
5. Disconnect and remove the flue couplings and inner
vent/flue pipe (GUCA Only) along with rubber elbow
(Standard Vent/Flue Connection) or rubber coupling (Al-
ternate Vent/Flue Connection) that are attached to in-
duced draft blower.
6. Remove the top cover assembly from furnace cabinet.
This must be removed to gain enough clearance to re-
move the heat exchanger assembly.
7. Remove the primary limit, manifold assembly and ori-
fice shield, pressure switches and induced draft blower.
These components do not have to be unwired since
there is enough wire for them to be laid in the blower
compartment area out of the way.
8. The final step in removing the heat exchanger assem-
bly is to remove the screws that hold heat exchanger
assembly to the inside rails. After removing the screws
remove the permagum located in the top and bottom
corners of the cabinet that is used to help seal the burner
compartment, lift up on heat exchanger assembly and
slide out of the cabinet.