Testing Auxiliary Limit; Checking Burner Temperature Switch - Amana APUM3 M41AA Series Service And Troubleshooting

SERVICING
The control will automatically reset when the temperature
within the combustion chamber is sufficiently lowered.
High Voltage!
Disconnect all power before servicing or
installing. Multiple power sources may be
present. Failure to do so may cause property
damage, personal injury or death.
Do not bypass safety devices.
1. Remove electrical power to unit. Some units may
have more than one source of power.
2. Remove the wires from the limit control terminals.
3. Using an ohmmeter, test for continuity across the two
terminals.
4. If limit test open allow unit to cool and retest.
5. If still open, replace the control.

Testing Auxiliary Limit

The auxiliary limit control is a preset nonadjustable control
mounted in the blower compartment area.
It is connected in series with the burner temperature
switch wiring to the gas valve. If its temperature should be
exceeded, it will open, interrupting the voltage to the gas
valve causing it to open.
An additional limit (primary limit) control is required for
safety control of high temperature within the furnace or
ductwork.
AUX. LIMIT
WARNING
WARNING
High Voltage!
Disconnect all power before servicing or
installing. Multiple power sources may be
present. Failure to do so may cause property
damage, personal injury or death.
1. Remove the wires from the auxiliary limit control
terminals.
2. Using an ohmmeter, test for continuity across the two
terminals. No reading indicates the control is open.
Push the red reset button, test again - if still open,
replace the control.
Testing Auxiliary Limit Control

Checking Burner Temperature Switch

*PU units are equipped with a temperature-activated auto
reset control. This control is mounted to the burner box
assembly and is wired in series with the auxiliary limit
and gas valve. The control is designed to open should
the temperature exceed the designed box temperature.
An over firing condition or flame impingement on the heat
shield can also cause the control to open.
WARNING
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