Installation manual
Page 46 / IM 178
Check, Test, and Start Procedures
Electric shock and moving machinery hazard. Can cause severe equipment damage, personal injury, or death.
All start-up and service work must be performed by qualified technicians who are familiar with the hazards of working on
this type of equipment.
Do not attempt to operate or service this equipment without first reading and understanding this manual, the “MicroTech
Applied Rooftop Unit Controller” manual (Bulletin No. IM 483), and the applicable operation manual (Bulletin No. OM 108,
OM 109, or OM 110).
Assure that the frame of the equipment is bonded to the building electrical ground by use of the grounding terminal or by
other acceptable means.
Disconnect electrical power before servicing this equipment.
All units are completely run tested at the factory to assure
proper operation in the field. Nevertheless, the following
check, test, and start procedures must be performed to
properly start the unit. To obtain full warranty coverage, the
check, test, and start form supplied with the unit must be
completed, signed, and returned to McQuay International.
A representative of the owner or the operator of the
equipment should be present during start-up to receive
instructions in the operation, care, and maintenance of the
unit.
Before Start-up
1. Verify that the unit is completely and properly installed
with ductwork connected. Verify that all construction
debris is removed, and that the filters are clean.
2. Verify that all electrical work is complete and properly
terminated. Verify that all electrical connections in the
unit control panel and compressor terminal box are
tight, and that the proper voltage is connected.
3. Verify that gas piping is complete and leak tight. Verify
that the shutoff cock is installed ahead of the furnace,
and that all air has been bled from the gas lines.
4. Manually rotate all fans and verify that they rotate freely.
Verify that the belts are tight and the sheaves are aligned.
5. Verify that all setscrews and fasteners on the fan assem-
blies are still tight. Do this by reading and following the
instructions in “Setscrews” which is in the “Mainte-
nance” section of this manual.
6. Verify that the evaporator condensate drain is trapped,
and that the drain pan is level.
7. If unit is curb mounted, verify that the curb is properly
flashed to prevent water leakage.
8. Before attempting to operate the unit, review the control
layout description to become familiar with the control
locations.
Review the equipment and service literature, the
sequences of operation, and the wiring diagrams to
become familiar with the functions and purposes of the
controls and devices.
Determine which optional controls are included with
the unit.
9. Before closing the power disconnect switch, open the
following unit control circuit switches:
a. Main Control Panel
• Turn system switch S1 to “off.”
• Electric heat units: turn switch HS1 to “off.”
b. Furnace Control Compartment
• Turn furnace switch S3 to “off.”
10. If the VAV or CAV-DTC unit does not have an optional
zone temperature sensor (ZNT1) connected to it, change
the entry under keypad menu item 28C (“Space Sensor=”)
from “Yes” to “No.”
11. If desired, all MicroTech internal control timers can be
reduced to 20 seconds by changing the entry under
keypad menu item 28B (“Timers=”) from “Normal” to
“Fast.” This will reduce the delays associated with
normal control action for 15 minutes or until the entry is
changed back to “Normal.”
Power-up
1. Close the unit disconnect switch.
2. Turn the S1 switch to “on.” Power should now be sup-
plied to the MicroTech controller, and the LEDs on MCB1
(red, green, and amber) should follow the normal start-
up sequence (refer to the “Component Data” section of
IM 483).
1. If the unit has no controls, check the fan rotation and
continue on to step 3. If the unit is equipped with an
optional Remote Monitor Panel, turn the on-off switch to
“on,” and turn the heat-auto-cool switch to “auto.”
2. If the unit has no controls, check the fan rotation and
continue on to step 3. For units with MicroTech control,
place the unit into the “Occ-Fan Only” mode through
keypad menu 11 (“Control Mode”). The controller should
enter the “Startup Initial” operating state. After the Startup
Fan Start-up
Initial timer has expired (3 to 4 minutes), the fans should
start. Observe the fan rotation and, if it is backwards,
disconnect power and reverse two legs of the power supply.
If a fan does not run, do the following:
a. Check the control circuit fuse F1.
b. Verify that the overloads have not tripped.
c. Check the fan motor power fuses.
d. Verify that the Remote Monitor Panel wiring (if any) is
correct.
e. Trace the circuits.
!
WARNING