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MESSAGING & NAVIGATION
HeatNet Control V3 3.x
Page 96
Failsafe: Low DHW
Temperature
The boiler has entered Failsafe mode due to a low DHW temperature.
Failsafe: Low
Header
Temperature
The boiler has entered Failsafe mode due to a low Header temperature.
Failsafe: Low
Return
Temperature
The boiler has entered Failsafe mode due to a low Return temperature.
Failsafe: Low
Supply
Temperature
The boiler has entered Failsafe mode due to a low Supply temperature..
Fault
A problem condition has been detected that shuts the boiler down or will not allow it to start.
This condition can occur erther on the Interlocks or can be software generated.
Fuel Change (Dual
Fuel) is in Progress
If the boiler is configured for dual fuel
–
displays during a changeover.
Gas Pressure is
too High or Low
If the GAS PR opens on J11A.7 & J11A.8 due to a gas pressure issue.
Heat Exchanger
Protection Fault
When a Heat Exchanger Protection Fault is triggered the display will show "Heat Exchanger
Protection Fault", and a corresponding log entry will be made. Heat exchanger monitors are
mounted on a bracket near the burner viewport; there is one on each heat exchanger. The heat
exchanger has a status LED to provide operational feedback.
Heating
The system is in a heating mode, but none of the boilers are firing.
High/Low ∆T
limited
Algorithm that looks at High ∆T or Low ∆T to protect boiler from thermal shock/stress. When
this is displayed firing rate is limited
Ignition Control
Alarm
Occurs when the Ignition Control closes it alarm relay
–
Input on J5 FLAME SAFE ALARM. The
ignition control alarm is displayed if the ignition control detects a fault. This could be a flame
failure, air proving switch, or other fault associated with the ignition control. When this fault
occurs, you will need to refer to the ignition control for the reason.
Input Clamped at
Modulation
Maximum
This clamp ensures that until all boilers are running, the input is limited to minimize over firing
the system when new boilers are added. It also limits the boiler’s input before servicing a
request to go to high fire (preventing thermal shock).
Input Clamped for
Protection
(Operating Limit)
This clamp is active when the supply water temperature is in the Operating Limit Band (Yellow
part of the Heating bar). It is used to limit the input of the boiler in order to minimize cycling off
the Operating Limit.
Input is limited to
½ rate
The boiler is in a protection mode, High/Low Delta
–
firing rate limited.