Microtech 2300 - Sequence of Operation

SEqUENCE OF OPERATION
MICROTECH 2300 UNIT CONTROLLERDAIKIN APPLIED
10
Sequence Of Operation
Fan Only
On a call for fan the fan starts immediately through the activation
of the Thermostat G terminal or Room Sensor Fan Switch.
LED Activity Type Color Description
1 Flash Mode Green
No Call for Heating/Cooling/
Dehumidication
4 Flash Mode Green Call for Fan Only
NOTE: If conguration switch SW2 on the main control board is OFF the fan will
run continuous whenever there is a power supply to the unit. For cycling
fan operation conguration swithc SW2 needs to be on.
Cooling
LED Activity Type Color Description
1 Flash Mode Green
No Call for Heating/Cooling/
Dehumidication
2 Flash Mode Green Call for Cooling
On a call for 1st stage cooling from a thermostat or network
setpoint, the H6 output on the MT2300 board is activated to
open the motorized valve to allow water ow through the heat
exchanger. The fan starts immediately (unless it is already
on through activation of the G terminal by the thermostat fan
switch “ON” or a wall sensor command) at “FAN ONLY” setting.
The compressor starts after 60 seconds to make sure the
motorized valve has fully open for proof of water ow and the
fan CFM output increases. The compressor minimum on timer
of 180 seconds starts. The reversing valve will de-energize 5
seconds after the compressor starts. The fan CFM output is now
determined by the MT2310 I/O board conguration switches
SW1-SW4 and the corresponding stage 1 CFM. If a two stage
thermostat is used, a further demand for cooling will change
(increase) the CFM output of the EC fan motor.
When the room setpoint conditions are satised, the compressor
will shut o󰀨 and the fan will either shut o󰀨 (fan switch “AUTO”)
or continue to run (fan switch “ON” or conguration switch SW2
is OFF). The compressor minimum o󰀨 timer of 360 seconds will
start.
Heating
LED Activity Type Color Description
1 Flash Mode Green
No Call for Heating/Cooling/
Dehumidication
3 Flash Mode Green Call for Heating
On a call for 1st stage heating, from a thermostat or network
setpoint, the H6 output on the MT2300 board is activated to
open the motorized valve to allow water ow through the heat
exchanger. The fan starts immediately (unless it is already on
through activation of the G terminal by the thermostat fan switch
“ON” or a wall sensor command) at low CFM. The compressor
starts after 60 seconds to make sure the motorized valve
has fully open for proof of water ow and the fan CFM output
increases. The compressor minimum on timer of 180 seconds
starts. The reversing valve will energize 5 seconds after the
compressor starts. The fan output is now determined by the
MT2310 I/O board conguration switches SW1-SW4 and the
corresponding stage 1 CFM. If a two stage thermostat is used,
a further demand for heating will change (increase) the CFM
output of the EC fan motor. When the room setpoint conditions
are satised, the compressor will shut o󰀨 and the fan will either
shut o󰀨 (fan switch ”AUTO”) or continue to run (fan switch “ON”
or conguration switch SW2 is OFF). The compressor minimum
o󰀨 timer of 360 seconds starts.
Boilerless Electric Heat Mode
Units equipped with the boilerless electric heat option include
an entering water temperature sensor. On a call for heating
the fan starts immediately (unless it is already enabled through
activation of the G terminal from the thermostat fan switch “ON”
or a wall sensor command.) at “FAN ONLY” setting. The H6
output on the MT2300 board is activated to open the motorized
valve allowing water ow thru the heat exchanger. If the entering
water temperature is below set point, (55°F standard units or
28°F for geothermal units), the MT2300 controller will disable the
compressor, increase the fan speed to electric heat CFM and
energize a 24VAC output to the electric heat control circuit. When
the room setpoint conditions are satised, the electric heater will
turn o󰀨 and the fan will either cycle o󰀨 (fan switch “AUTO”) or
continue to operate (fan switch “ON” or conguration switch SW2
is OFF). If the entering water temperature is above setpoint, the
unit will operate in compressor heating mode. The setpoints are
adjustable by the BAS.
Supplemental Electric Heat Mode
On a call for supplemental electric heat (W3) or BMS setpoint,
the compressor will continue to operate, the fan speed will
increase to the electric heat setting and electric heating will
energize. For units equipped with two stages of electric heat, W4
or BMS setpoint will turn on second stage of electric heat.
Emergency Electric Heat Mode
On a call for emergency heat, the fan will energize at its “electric
heat” setting. When the room setpoint conditions are satised,
electric heat will be de-energized. The fan will operate according
to its “FAN ONLY” setting when enabled, for continuous fan
operation. If fan cycling is enabled, the fan will turn o󰀨 once room
setpoint conditions are satised. A 24V control signal to TB1-W4
from the thermostat or BMS will initiate a call for stage 2 electric
heat.
Hydronic Heat Mode
This mode requires optional hydronic heat factory installed on
vertical units. A hydronic coil, 3-way valve and entering water
temperature sensor are included with this option. The purpose of
this mode is to satisfy the heating demand by using the elevated
loop water temperature between 90°F and 120°F.
On a call for 1st stage heating with entering loop water above
90°F the H6 output on the MT2310 I/O expansion module is
activated to open the motorized valve diverting water ow to the
hydronic coil. The fan starts after 30 seconds (unless it is already
activated by the thermostat or room sensor). The fan output is
determined by the MT2310 I/O expansion module conguration
switch. When the room setpoint conditions are satised, the