Effective: October 2018
2 of 12
F-35-2000
FEATURES
The PIM provides the following features:
•
Integrated UL353 High Limit using Thermistor Sensor
•
Configuration parameters selected through a unique
Identification Card
•
Communicates via (RS485) with Host Controller
•
Supports tN4 signals when using tekmar Host
Controller
•
Measures Inlet, Outlet, Limit, and Vent temperatures
using NTC curve
J Thermistors, 10 K
Ω
(
β
3892) at 25°C (12 K
Ω
Thermistors optional).
•
Optional signals from DHW, System, and Outdoor Air
sensors to Host Controller for Outdoor Reset and DHW
functions.
•
Supports external input (0-10 VDC or 4-20 mA) from an
Energy Management System
•
Controls the Boiler, System, and DHW pumps
•
Controls the gas ignition sequence in response to space
heating or DHW demand
•
Pulsed Water Flow sensor input for optimizing DHW
performance
•
Modulates the boiler firing rate using combustion
blower speed control, providing a PWM output or a 4-
20 mA signal.
•
Closed-loop control of blower speed (RPM) through
tachometer signal monitoring
•
Optional support for two-stage blowers by re-assigning
the DHW pump relay
•
Low-voltage detection and safe shutdown below
18.0VAC supply input
•
Hot Surface or Direct Spark Ignition (also allows for
external HV transformer)
•
Intermittent Pilot Ignition (single stage only)
•
Fail-safe Control for one or two stages of gas valves
•
Optional Isolated (Dry) Contact Gas Valve operation
•
Airflow, water flow and gas pressure switch monitoring
and diagnostics
•
Optional automatic reset after ignition lockout (one
hour or as defined)
•
Safe-Start and full-time Flame sensing
•
Local (through the HSI or DSI element) or Remote
Flame sensing
•
Configurable as needed to meet CSD-1 applications
•
System and Control Diagnostics through use of on-
board or remote LED
•
Communication of Diagnostic status to Host Controller
•
Manual Reset for Ignition Lockout or Hi-Limit (on-board
or remote)
•
Field Test/pump exercise capability
•
Dry contact relay output for Alarm and Alert conditions
•
Capability of two PIM operation to support up to 4 gas
valve stages using a master/member configuration
SENSORS
The PIM provides standard support for 10K ohm @ 77°F NTC
curve J Thermistor probes (
β
=3892). Special OEM models may
support other sensor types as outlined in the specific appliance
manuals. Optional 12k Ohm thermistor are available, consult
factory for details.
The Inlet, Outlet, Hi-Limit, and Vent (exhaust stack) sensors are
directly processed by the PIM. The optional System, Outdoor,
and DHW tank sensors are also connected to the PIM but passed
through to the tekmar Host Controller which is required to
provide those additional features.
ID CARD
The PIM determines its operating parameters by reading the
identification code of an external plug-in ID card.
Note:
This ID card must be present for the PIM and
appliance to operate.
A total of up to 126 unique codes are supported. This card
selects the proper settings in the PIM's memory for appliance
models. These parameters include ignition timings and
operation; and system and OEM configuration settings.
Fenwal supplies the PIM with its internal ID card settings blank.
The first time a PIM is powered-up attached to an ID card, the
PIM stores the ID card setting in non-volatile memory. Once set,
the PIM only operates with the correct ID card installed that
matches the PIM’s internal ID settings. The PIM verifies the ID
card at power-up.
If a PIM needs to be re-configured for another ID card, such as
during service or replacement, its internal ID card settings must
be cleared. Contact the manufacturer for ID card reset process.
SEQUENCE OF OPERATION
Install the ID Card
The PIM must always have the proper ID card attached for
operation. The ID card is connected to J6 and determines the
correct configuration parameters and system timings for a
particular application. The ID card must always remain with the
appliance, even if the PIM needs to be replaced.
Potentiometer (Operator Setpoint)
The operating setpoint for PIM stand-alone mode is selected by
manually adjusting a potentiometer. The operating point for
outlet water temperature is settable from 110°F to 210°F.
Note:
The operating setting used by the software limits the
maximum setpoint to the configured operator
safeguard (delta below the configured high limit
setpoint) to avoid nuisance trips regardless of the
potentiometer position.
WARNING
The ID card must remain with the appliance
for its entire service life. In the event of an ID
Card failure, replacement must be performed
by a qualified technician and must be
replaced with an ID card of the same number.
ID Cards cannot be interchanged between
appliances.
