Effective: October 2018
F-35-2000
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3. The control attempts two additional ignition trials
before going into lockout and the gas valve relay(s) are
de-energized immediately.
4. The LED indicates the fault code for ignition lockout.
Lockout Reset
Volatile Reset Models
Recovery from lockout requires either pressing manual reset,
recycling the call for heat, or removing 24 volts for a period of 5
seconds. On models with automatic reset, if the call for heat is
still present after the configured reset time, the control will
automatically reset and attempt to start a new heating cycle.
Manual Reset Models
Recovery from lockout requires activation of the manual reset
switch or remote reset input.
High Limit Fault Reset
If the High Limit sensor detects a temperature above the High
Limit setpoint, the PIM will enter lockout. Recovery from a High
Limit fault requires activation of the manual reset switch or
remote reset input.
FLAME FAILURE RESPONSE
Recycle Mode
With "recycle after loss of flame", upon loss of flame, the gas
valve is de-energized within 0.8 seconds. After the flame recycle
delay, the control attempts to relight the burner. Multi-try
models allow three tries for ignition including inter-purges. If the
pilot burner relights, normal operation resumes. If the burner
does not relight, the control will go into lockout as described in
“Failure to Light - Lockout”.
Re-ignition Mode (Spark Models Only)
If the established flame signal is lost while the burner is
operating, the control responds within 0.8 seconds by energizing
the HV spark for the TFI period in an attempt to relight the
burner. If the flame is re-established, normal operation resumes.
If the burner does not light within the TFI, the gas valve is de-
energized immediately and on multi-try models a new TFI
sequence begins. Multi-try models will make 2 more attempts to
light the burner.
If the burner does not relight, the control will lockout as
previously described in “Failure to Light - Lockout”.
OEM FACTORY WIRING
Supplying Power
The PIM requires 24 VAC on Connector J11 to operate its
microprocessor circuits, the safety switch connections, and the
field demand inputs. An onboard fuse protects the 24 VAC
circuits and if configured for direct gas valve power, the 24 VAC
relay outputs to the gas valves.
Sensor Inputs
The PIM requires an outlet thermistor sensor for burner control
and a high-limit thermistor sensor for the integrated UL353 high-
limit function. These two thermistors must be independent but
co-located so they provide similar readings. The vent sensor and
inlet sensor are optional and if used should be enabled by the
parameter table settings.
Isolated Valve Contacts
If the optional isolated valve configuration is used, the valve
power and return must be separately supplied to J12 and the
valve outputs are not protected.
Combustion Blower Connections
The blower motor is connected to J13 operating off the power
supplied to L1, which can be 120VAC or 240VAC. If a modulating
blower is used, PWM or 4-20 mA signals are provided by
connection to J10. The blower motor tachometer signal is
required when configured for closed-loop fan speed control.
High-Current Blower Option
If provided, the relay contacts of K5 must be used to connect the
blower. The QC dry-contact terminals on top of the relay are
used for the blower output and supply voltage, which may be
120VAC or 240VAC. The maximum current rating is 15.0A.
Pump Outputs
The pump circuits are operated off the power supplied to L1 and
L1-S, which can be 120VAC or 240VAC. The boiler pump and
DHW pump are sourced from L1, while the supply pump (if
used) must be powered by L1-S.
Ignition Outputs
The PIM is capable of DSI, IP, or HSI ignition depending on
configuration. For spark ignition (DSI or IP) the electrode is
connected to the T3 ignition coil. For HSI the igniter element
connects to P1 and is driven off the L1 supply voltage.
If configured, an external spark ignition transformer can be used
by connecting it to P1. It is powered by L1 and the spark output
on T3 will be disabled.
SYSTEM CONNECTIONS (FIELD WIRING)
If used, the Host Controller must be connected to J4. The RJ-45
style 8-pin jack provides power, communications, and sensor
information to the Host Controller.
The PIM also acts as the central wiring point of a hydronic
system. Field wiring terminals on J1 and J2 allow connection of
optional DHW, outdoor, and system sensors, Host Controller,
EMS analog demand signal, LWCO, remote reset, water flow
switch, and the space thermostat and DHW demand inputs.
