www.DaikinApplied.com 26
LARGE VERTICAL WSHP IM 1059-12
7 .
If the thermostat operates but stops after a brief period:
a. Is there proper airflow? Check for dirty filter,
incorrect fan rotation (3-phase fan motors only),
or incorrect ductwork.
b. Is there proper water flow rate within temperature
limits? Check water balancing; back-flush unit if
dirt-clogged.
8 .
Check for vibrating refrigerant piping, fan wheels, etc.
9 .
Do not lubricate the fan motor during the first year of
operation as it is pre-lubricated at the factory.
10 .
Field supplied relays installed on the input terminals
W1, W2, Y1, Y2 or G may introduce electrical noise.
Never install relay coils in series with the inputs.
Control options
The control enclosure houses the major operating
electrical controls including the MicroTech III controller
and I/O expansion module, control transformer,
compressor relays and fan relay. Each component is
easily accessed for service or replacement.
Three unique control choices are offered with the
MicroTech III control system:
■
Standalone operation using a MicroTech III
controller and I/O expansion module
■
MicroTech III controller with I/O expansion module
and
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on
W
orks
® communication module
■
MicroTech III controller with I/O expansion module
and BACnet® communication module
Each option features direct quick-connect wiring to all
unit-controlled components for “clean” wiring inside the
control box. Each control circuit board receives power
from a 75 VA transformer.
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-u
P
Figure 18: Control options
Control
Description
Application
Protocol
MicroTech III
(Standalone) Unit
Controller with I/O
Expansion Module
The MicroTech III controller is a
standalone microprocessor-based
control board conveniently located
in the unit control enclosure for easy
accessibility. The board is designed to
provide thermostat control of a Water
Source Heat Pump using a two-stage
wall thermostat. The unit controller
provides unit-wide control of the WSHP
and control of the first refrigerant circuit.
Each unit controller is factory
programmed, wired, and tested for
complete control of single zone,
standalone operation of your Daikin
Water Source Heat Pump.
Unit-mounted or wall-
mounted thermostat or room
sensor
The I/O Expansion Module is an
extension of the Microtech III controller
and provides control of the second
refrigerant circuit. External LED status
lights display fault conditions to provide
easy troubleshooting and diagnosis of
the second circuit.
Allows for:
Control of second refrigeration circuit,
secondary heating options and
cooling/dehumidification options.
L
on
W
orks
Communication
Module
The MicroTech III control system
accepts a plug-in
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orks
commu nication module to provide
network communications and added
functionality to easily integrate with
an existing BAS. The communication
module can be factory- or field-installed
and is tested with all logic required to
monitor and control the unit.
LonTalk application protocol is
designed for units that are integrated
into a
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orks
communication
network for centralized scheduling
and management of multiple heat
pumps.
L
on
M
ark
3.4 Certified
BACnet
Communication
Module
The MicroTech III controller accepts a
plug-in BACnet commu nication module
to provide network communications
and added functionality to easily
integrate with an existing BAS. The
communication module can be factory-
or field-installed and is tested with all
logic required to monitor and control
the unit.
Designed to be linked with a
centralized building automation
system (BAS) through a BACnet
communications network for
centralized scheduling and
management of multiple heat pumps.
BACnet
MS/TP