Instruction manual

50
P/N HN-IOM-1 82-0331 Copyright 2009 Mestek, Inc.
Finned copper tube gas boilers & water heaters – Control manual
FAULT EVENT &
INTERLOCK
TERMINALS
CAUSE/Discussion DISPLAY Action required to
reset from fault
GAS PRESSURE
(J11A, GAS PR)
Occurs on opening of gas pressure switches connected to
J11A GAS PR terminals. e high and low gas pressure
switches are wired in series. Opening of either switch will
cause this fault.
e boiler is shut down until the fault is corrected.
e display continues showing the SUPPLY, HEADER or
other temperature, whichever had been selected for display.
e temperature shown is the value detected at the sensor
listed.
FAULT SUPPLY
GAS PRESSURE
168°F
Automatically resets
control aer condition
is corrected
HIGH LIMIT
(J5, HIGH LIMIT)
Occurs on opening of an external limit connected to J5
HIGH LIMIT terminals. e boiler is shut down until the
fault is corrected.
e display continues showing the SUPPLY, HEADER or
other temperature, whichever had been selected for display.
e temperature shown is the value detected at the sensor
listed.
FAULT SUPPLY
HIGH LIMIT
168°F
Automatically resets
control aer external
limit closes
IGNITION CTRL ALARM
Occurs when the HeatNet control receives an alarm signal
from the ignition control. is could occur on ignition
failure, air proving switch error, or any other fault that
triggers the ignition control’s alarm circuit. e boiler is
shut down until the fault is corrected.
e display continues showing the SUPPLY, HEADER or
other temperature, whichever had been selected for display.
e temperature shown is the value detected at the sensor
listed.
FAULT SUPPLY
IGNITION CTRL ALARM
168°F
Automatically resets
control aer external
signal ends
INTERLOCK SPARE 3
(J11A, SPARE 3)
Occurs on opening of an external device connected to J11A
SPARE 3 terminals. e boiler is shut down until the fault
is corrected.
e display continues showing the SUPPLY, HEADER or
other temperature, whichever had been selected for display.
e temperature shown is the value detected at the sensor
listed.
FAULT SUPPLY
INTERLOCK SPARE 3
168°F
Automatically resets
control aer condition
is corrected
INTERLOCK SPARE 4
(J11B, SPARE 4)
Occurs on opening of an external device connected to J11B
SPARE 4 terminals. e boiler is shut down until the fault
is corrected.
e display continues showing the SUPPLY, HEADER or
other temperature, whichever had been selected for display.
e temperature shown is the value detected at the sensor
listed.
FAULT SUPPLY
INTERLOCK SPARE 4
168°F
Automatically resets
control aer condition
is corrected
IRI ALARM
Occurs when the HeatNet control receives an alarm signal
from the gas valve. e boiler is shut down. If the condition
isn’t corrected within one minute, CALL FACTORY
appears on the display.
Check the gas valve if this fault appears.
e display continues showing the SUPPLY, HEADER or
other temperature, whichever had been selected for display.
e temperature shown is the value detected at the sensor
listed.
FAULT SUPPLY
IRI ALARM
168°F
Requires cycling
the boiler ON/OFF
switch to reset aer
condition is corrected
Table 11 Status screen fault displays (continued)
Troubleshooting (continued)
9