Laars MFTHW199 - Page 70

LAARS Heating Systems
Page 68
Error
Code
Error Code Description Possible Remedies
Recover
methods
70
Register, Ram, Rom, I/O
Port, AD Abnormal, Important
EPROM Data or Safe Data
Abnormal
This Error Code will go away when the condition is remedied.
If Error happens again:
1. Turn power OFF and ON at the main power switch internal to the appliance.
2. If the problem persists, replace the main control.
Soft Lock
72
Flame Signal Detected before
Ignition
This Error Code will go away when the condition is remedied.
If Error happens again:
1. Check the appliance cover. Ensure it is secure. Flame detection sensor can detect
an external light source.
2. Check flame detection sensor. Ensure connections are secure. Normal operating
settings are more than 2.5DC before ignition, less than 2.5DC after ignition.
3. If the problem persists, replace the main control.
Soft Lock
76
Poor Communication
(Control Display)
This Error Code will go away when the condition is remedied.
If Error happens again:
1. Check connections from main control to display panel.
2. If the problem persists, replace the display and/or the main control.
Soft Lock
78 Cascade Error Please refer to Laars Document 1349 for Cascading the Mascot FT.
80
Low Water Level Sensor
(Low Water Level Detected
Four (4) Consecutive times)
This Error Code will go away when the condition is remedied.
If Error happens again:
1. Ensure all valves are open to the appliance and there are no leaks.
2. Ensure all air has been purged from the system.
3. Check wiring connections to low water level sensor. Ensure all are secure.
4. Check low water level sensor resistance. If resistance is zero, replace the sensor.
5. If the problem persists, replace the main control.
Soft Lock
81 Low Water Level Circuit
This Error Code will go away when the condition is remedied.
If Error happens again:
1. Ensure all valves are open to the appliance and there are no leaks.
2. Check wiring connections to low water level sensor. Ensure all are secure.
3. Check low water level sensor resistance. If resistance is zero, replace the sensor.
4. If the problem persists, replace the main control.
Soft Lock
85
Freeze Protection
(Appliance has detected
water temperature below
34°F(1°C)
This Error Code will go away when the freezing condition is remedied.
If Error happens again:
1. Ensure appliance is located in a mechanical room protected from freezing conditions.
2. Ensure all valves are open to the appliance, there are no leaks.
2. Check wiring connections to low water level sensor. Ensure all are secure.
3. Check low water level sensor resistance. If resistance is zero, replace the sensor.
4. If the problem persists, replace the main control.
Soft Lock
94
Exhaust Sensor detects Vent
Temperature is Greater than
190oF (88oC)
This Error Code will go away when the condition is remedied.
If Error happens again:
1. Check if dip switch Max Fire setting is ON. Switches 6 and 7 should be OFF for
normal operation.
2. Check exhaust temperature sensor. Ensure connections are secure.
3. Check sensor resistance. If resistance is zero, replace the sensor.
4. Check exhaust vent for blockage.
5. If the problem persists, replace the control.
6. If the problem persists, replace the heat exchanger.
Soft Lock
SECTION6.Error Codes (continued)