United cool air C13-Series, Installation, Operation And Maintenance Manual

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Installation, Operation and Maintenance Manual
C13-Series
36 Subject to change without notice. 10.20-IM (0818)
Air-Cooled Unit
Start-Up Procedures (R-410a Systems)
Some of the numbered items below are referenced on the
Start Up Form that needs to be completed�
This procedure has been created based on utilizing a
standard wall thermostat� If another controller is being
utilized some of the steps below may need to be altered�
1� Start up must be performed by a qualified HVAC
Technician�
2�
Make certain that all power is disconnected at the main
power circuit breaker or service disconnect before
starting any of this procedure�
3� Check all electrical screw terminals and wiring lugs
for tightness internal to the equipment� Components
may have loosened due to vibration during transit
or handling� Verify that the main power block lug
connections made in the field are tight and secure.
4� Confirm that the voltage rating of the equipment data
tag coincides with the power that will be delivered to
the unit�
5� Verify that the circuit protection for the unit satisfies
Local and National Codes according to the unit data
tag Minimum Circuit Ampacity (MCA) and Maximum
Fuse Size (MFS)�
6�
Locate the unit thermostat and check all electrical
terminations against the unit electrical diagram and for
the unit thermostat�
Note: If using a digital thermostat with a “C” (Common)
terminal, this terminal MUST be terminated to the “C”
terminal in the unit� Failure to do so will result in the
thermostat shorting out and being destroyed�
7� Leak check the refrigerant system� While the unit was
leak checked at the factory, leaks can develop during
transit and / or handling�
8� Confirm that the unit condensate has been adequately
trapped and taken to a suitable point for disposal�
9� Verify that the filters are in place, clean and usable.
10�
Switch the unit thermostat to the “OFF” position�
11� Apply power to the unit� Switch the circuit breaker or
field supplied electrical service disconnect switch to the
on position�
Note: If the unit has the flooded condenser option the scroll
compressors will have crankcase heaters� If the
outdoor ambient is 70˚ F or lower, let the compressors
sit for approximately 24 hours before proceeding�
12� Record the voltage at the unit terminals�
13� If possible with the thermostat provided, switch the
evaporator blower to the RUN position� Verify that the
evaporator blower is activated�
14� Verify that the evaporator blower is rotating in the
correct direction (three phase units only)�
Note: If the evaporator blower motor runs backwards,
shut off all power to the unit� Switch any two of the
incoming power leads at the unit terminal block�
The unit has been wired and phased properly at the
factory� DO NOT change any factory wiring to correct
for a phase problem�
Note: Before conducting the following start up sections
connect a suitable refrigerant gauge set to the unit
Schrader connections� Install temperature sensors to
record the appropriate refrigerant line temperatures�
Service gauge access ports have been provided in
the cabinet corner posts so that the gauge line hoses
can be run outside the cabinet with the access panels
installed�
15� Set the thermostat switch to a temperature set point
approximately 5˚ lower than the space temperature. Set
the thermostat fan switch to the AUTO position� Set the
thermostat operating mode to the COOL position� This
should energize the compressor(s) and both blowers�
Note: Dependent upon the options and/or the thermostat,
there may be a delay for the compressor(s) operation�
16� Verify that the condenser blower rotation is correct�
17� While waiting for the compressor(s) to stabilize,
record the External Static Pressure (ESP) for both the
evaporator and condenser blowers�
Note: Make sure all the unit access panels are in place when
taking these readings�
18� Record the return air temperature to the evaporator coil
along with the supply air temperature� (The unit should
have operated for at least 15 minutes before taking
these readings)�
19� Record the outdoor ambient entering the condenser
coil along with the discharge air temperature of the
condensing section�
20� Record the suction line pressure and the suction line
temperature for each circuit near the compressor�
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