Start-up and operation
Start the unit. Refer to the
Startup and Performance Checklist
(
Form 145.13-CL1
) to check the rotation
of the fans and compressors. Scroll compressors only compress in one rotational direction. Three
phase compressors rotate in either direction depending upon phasing of the power. There is
a 50-50 chance of connecting power in a way that causes rotation in the reverse direction. It is
important to ensure the proper rotation direction is achieved when installing and operating the
system.
Note:
Prior to start-up it is important to ensure proper compressor and fan rotation direction
is achieved when the system is installed and operated.
To ensures proper unit operation, monitor the microprocessor board for any fault codes. Verify the
proper compressor direction by observing that, when the compressor energizes, the refrigerant
suction pressure drops and the refrigerant discharge pressure rises. Reverse compressor rotation
also results in an elevated sound level and a substantially reduced current draw.
There is no negative impact on durability caused by operating three phase scroll compressors in
the reversed direction for a short period of time (under one hour). However, after several minutes
of operation, the compressors' internal protectors trip. If opposite rotation is needed, disconnect
and reverse any two leads of the three phase supply. Then, reconnect the power.
Table 23: Pressure switch settings – all models
High
Low
Cut out (PSIG)
625
68
Cut in (PSIG)
500
107
Table 24: Refrigerant charge (lbs)
Unit
Circuit 1
Circuit 2
DSV060C
13.25 (13 lbs 4 oz)
-
DSV096C
11.35 (11 lbs 6 oz)
11.60 (11 lbs 10 oz)
DSV120C
13.90 (13 lbs 14 oz)
14.20 (14 lbs 3 oz)
DSV144C
16.60 (16 lbs 10 oz)
15.60 (15 lbs 10 oz)
DSV180C
19.50 (19 lbs 8 oz)
22.00 (22 lbs 0 oz)
DSV240C
25.00 (25 lbs 0 oz)
24.10 (24 lbs 2 oz)
DSV300C
32.00 (32 lbs 0 oz)
32.80 (32 lbs 13 oz)
Note:
Observe unit operation and check for unusual noise or vibration.
Note:
Always charge with liquid when adding R-410A refrigerant. Failure to do so
compromises the properties of the refrigerant being added to the rooftop unit and results in
substandard performance of the unit.
WARNING
The Air Conditioning section of this equipment is charged with R-410A; a high pressure refrigerant.
Only qualified technicians, using appropriately pressure rated test instruments, should perform
troubleshooting or service on this equipment.
D-Series Vertical (DSV060C-300C) Air-Cooled Self-Contained Units, C Generation with Smart Equipment Controller
38
Johnson Controls
