Troubleshooting; Primary Limit; Auxiliary Limit; Rollout Limit - Amana MSS9 Installation Instructions Manual

P L
RIMARY IMIT
The primary limit control is located on the partition panel and monitors heat exchanger compartment temperatures. It is a normally-
closed (electrically), automatic reset, temperature-activated sensor. The limit guards against overheating as a result of insufficient
conditioned air passing over the heat exchanger.
A L
UXILIARY IMIT
The auxiliary limit controls are located on or near the circulator blower and monitors blower compartment temperatures. They are
a normally-closed (electrically), manual-reset sensors. These limits guard against overheating as a result of insufficient conditioned
air passing over the heat exchanger.
R L
OLLOUT IMIT
The rollout limit controls are mounted on the burner/manifold assembly and monitor the burner flame. They are normally-closed
(electrically), manual-reset sensors. These limits guard against burner flames not being properly drawn into the heat exchanger.
P S
RESSURE WITCHES
The pressure switches are normally-open (closed during operation) negative air pressure-activated switches. They monitor the
airflow (combustion air and flue products) through the heat exchanger via pressure taps located on the induced draft blower and the
coil front cover. These switches guard against insufficient airflow (combustion air and flue products) through the heat exchanger
and/or blocked condensate drain conditions.
F S
LAME ENSOR
The flame sensor is a probe mounted to the burner/manifold assembly which uses the principle of flame rectification to determine
the presence or absence of flame.
T
ROUBLESHOOTING
E D
LECTROSTATIC ISCHARGE
NOTE: Discharge body's static electricity before touching unit. An electrostatic discharge can adversely affect electrical components.
Use the following precautions during furnace installation and servicing to protect the integrated control module from damage. By
putting the furnace, the control, and the person at the same electrostatic potential, these steps will help avoid exposing the
integrated control module to electrostatic discharge. This procedure is applicable to both installed and uninstalled (ungrounded)
furnaces.
1. Disconnect all power to the furnace. Do not touch the integrated control module or any wire connected to the control prior to
discharging your body's electrostatic charge to ground.
2. Firmly touch a clean, unpainted, metal surface of the furnace away from the control. Any tools held in a person's hand during
grounding will be discharged.
3. Service integrated control module or connecting wiring following the discharge process in step 2. Use caution not to recharge
your body with static electricity; (i.e., do not move or shuffle your feet, do not touch ungrounded objects, etc.). If you come
in contact with an ungrounded object, repeat step 2 before touching control or wires.
4. Discharge your body to ground before removing a new control from its container. Follow steps 1 through 3 if installing the
control on a furnace. Return any old or new controls to their containers before touching any ungrounded object.
D C
IAGNOSTIC HART
Refer to the Diagnostic Codes chart for assistance in determining the source of unit operational problems.
FAULT RECALL (96% Models Only)
The last five fault codes stored can be displayed on the diagnostic LED. When the control is in standby mode (no call for
heat or cool), press the FAULT RECALL switch for approximately two seconds or until the diagnostic LED turns off. Release
the switch and the LED will remain off for two seconds. Then the fault codes will display beginning with the most recent
fault first with a two second pause between codes. After the stored fault codes have all displayed, the LED will remain off
for two seconds and then turn on to indicate return to normal status. While displaying the stored fault codes, the control will
ignore any new call for heat, cool or fan.
FAULT CODE RESET (96% Models Only)
The stored fault codes can be erased from memory. When the control is in standby mode (no call for heat or cool), press the
FAULT RECALL switch for five to ten seconds or until the diagnostic LED begins to rapid flash. When the switch is released,
the LED will turn off for two seconds to indicate the codes are erased. After two seconds the LED will turn on to indicate
return to normal status. If the switch is held pressed for over ten seconds the rapid flash will stop and the LED will be on to
indicate return to normal status.
(ESD) P
RECAUTIONS
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