Heating System Startup; Air Balancing - Daikin Maverick II MPS062E Installation And Maintenance Manual

Heating System Startup

General
1. At the keypad, set the heating setpoints high enough so
that the controller calls for heating.Adjust the value in
Main Menu View\Set Unit\Heating\Occ Htg Spt = (above
the temperature shown in) Main Menu View\Set Unit\
Temperatures\Control Temp. In addition, on DAC units,
adjust the value in Main Menu View\Set Unit\Heating\
DAT Htg Spt above the temperature shown in Main Menu
View\Set Unit\Temperatures\Disch Temp.
2. Place the unit into heating mode through the keypad
menu Main Menu\quick Menu\Ctrl Mode = Heat Only.
3. Verify that the high ambient heat lockout temperature
setpoint, Main Menu\Commission Unit\Heating Setup\
Htg Hi OAT Lk is set above the current outside air
temperature (shown in Main Menu\View\Set Unit\
Temperatures\OA Temp).
Gas Furnace
Refer to the "Start-up and Operating Procedures" section of the
Forced Draft Gas Fired Furnace Installation Manual,
IM 685. Perform the start-up procedures given in it.
Electric Heat
Turn the electric heat switch HS1 to ON. The electric heaters
should energize. If the unit has multistage electric heat, the
MicroTech III Auxiliary Control board EHB1 should energize
the heaters in successive stages. The rate of staging is set in
keypad menu Main Menu\Commission Unit\Heating Setup\Htg
Stage Time. The default value of "5 min" can be adjusted from
2 to 60 minutes.
Steam Heat
The steam valve actuator should open the valve. The steam
valve is open when the valve stem is up. If the unit loses
power, the spring in the actuator should drive the valve wide
open. Check this by opening system switch S1.
Hot Water Heat
The hot water valve actuator should open the valve to the coil.
The three-way hot water valve is open to the coil when the
valve stem is down. If the unit loses power, the spring in the
actuator should drive the valve wide open to the coil. Check
this by opening system switch S1.
IM 991-2 • MAVERICK II ROOFTOP

Air Balancing

Moving machinery hazard. Can cause severe personalinjury or death.
Do not use a mechanically driven tachometer to measure the speed of
return fans on this fan arrangement. Use a strobe tachometer.
Rotating parts can cause severe personal injury or death Replace all belt/
fan guards that are temporarily removed for service.
Air balancing should be performed by a qualified air balancing
technician. Note that the supply fan motors are usually shipped
with variable pitch sheaves which are typically set at the low
end of the drive's fan rpm range. See
Motor Sheaves" on page
usually shipped with fixed pitch sheaves.
The following should be performed as part of the air balancing
procedure:
1. Check the operating balance with the economizer
dampers positioned for both full outdoor air and minimum
outdoor air.
IM 684 or
2. Verify that the total airflow will never be less than that
required for operation of the electric heaters or gas
furnace.
3. For VAV units that have fan tracking control, adjust the
supply/return fan balance by using the MicroTech III
controller's built-in, automatic capability. For complete
information on using this feature, see
III Applied Rooftop Unit Controller.
4. When the final drive adjustments or changes are
complete, check the current draw of the supply and
return fan motors. The amperage must not exceed the
service factor stamped on the motor nameplate.
5. Upon completion of the air balance, replace variable
pitch motor sheaves (if any) with comparably sized fixed
pitch sheaves. A fixed pitch sheave will reduce vibration
and provide longer belt and bearing life.
72
Check, Test, and Start Procedures
WARNING
WARNING
"Mounting and Adjusting
74. The return fan motors are
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