Troubleshooting guide

OM 931-3 / Page 19 of 28
Appendix B
MicroTech III Unit Controller with
LonWorks® Communication Module
For installation and operation information on LonWorks
Communication Module and other ancillary control compo-
nents, see:
■ IM 927 - MicroTech III Water Source Heat Pump
LonWorks Communication Module.
■ IM 933 - LonMaker Integration Plug-in Tool: For use with
the MicroTech III Unit Controller.
■ IM 955 - MicroTech III Wall Sensor for use with
Microtech III Unit Controller
Each Daikin McQuay water source heat pump can be
equipped with a LonWorks communication module that is
LonMark 3.4 certied to meet the LonMark Space Com-
fort Control (SCC) prole for heat pumps. The controller is
microprocessor-based and is designed to communicate over
a LonWorks communications network. It can be factory or
eld-installed.
The unit controller is programmed and tested with all the
logic required to monitor and control the unit. An optional
wall sensor may be used with the communication module to
provide limited local control of the Water Source Heat Pump.
The unit controller monitors water and air temperatures and
passes information to the communication module. The mod-
ule communicates with the BAS, to provide network control
of the Water Source Heat Pump.
Figure 9: LonWorks Communication Module
The MicroTech III unit controller with communication
module includes a unit-mounted return air, discharge air and
leaving water temperature sensor. Wall mounted temperature
sensors include setpoint adjustment and tenant override. The
user has the capability of substituting the wall sensor with a
duct-mounted return air sensor.
MicroTech III Unit Controller with LonWorks Communica-
tion Module orchestrates the following unit operations:
 Enable heating and cooling to maintain setpoint based on
a room sensor
 Enable fan and compressor operation
 Monitors all equipment protection controls
 Monitors room and discharge air temperatures
 Monitors leaving water temperature
 Relays status of all vital unit functions
The MicroTech III unit controller with
communication module includes:
■ Return Air Temperature sensor (RAT)(eld-installed)
■ Discharge Air Temperature sensor (DAT)(eld-installed)
■ Leaving Water Temperature sensor (LWT)
Note: Refer to IM 956-X for details to install (RAT) & (DAT)
sensors.
When an optional wall-mounted room temperature sensor is
connected to the unit controller, the Return Air Temperature
(RAT) sensor must not be installed. A wall-mounted room
temperature sensor and the return air temperature sensor
must not be connected simultaneously or the unit will not
operate properly.
CAUTION
The communication module provides access to setpoints for
operational control
Available wall sensors include:
 Room sensor with LED status and tenant override button
 Room sensor with LED status, tenant override button, and
±3°F setpoint adjustment
 Room sensor with LED status, tenant override
button, 55° to 90°F setpoint adjustment