Installation
Models 2–8 tons can be ordered as packaged, factory-charged unitized packages, or as factory-split.
The 10 ton model comes factory-split.
All units are lined with 1/2-inch thick and 2 pound density acoustical insulation to ensure quiet
operation. All models are provided with medium-efficiency 2-inch thick throwaway filters rated
MERV 7.
The 2–5 ton units use a single scroll compressor. The 8–10 ton units use a dual scroll compressor
with two independent refrigerant circuits. The 8 ton unit uses one single speed scroll compressor
and one two-stage scroll compressor, giving the unit three effective cooling stages. The 10 ton unit
features two 2 stage compressors, which allows for four stage cooling.
All units come standard with a Smart Equipment (SE) microprocessor control board with safety
controls and troubleshooting LEDs (see Microprocessor Controller on page 41 for more details).
Units operate reliably at outdoor ambient down to 50.0°F. In applications requiring operation below
this temperature, either a low ambient damper field kit accessory or low ambient control featuring
a variable frequency drive (VFD) on condenser fan is available (condenser fan VFD is available as a
factory installed option only on 8 and 10 ton units).
The damper is installed on the condenser air discharge and is allowed operation to 0.0°F ambient.
The VFD on the condenser is factory installed on the corner post in the condenser section of the
unit. The VFD on the condenser allows operation to 0.0°F ambient, which is needed to maintain a
proper refrigerant head pressure.
CAUTION
Only qualified personnel should perform installation and service of this equipment.
Pre-installation inspection of equipment
All units are factory tested to ensure safe operation and quality assembly. The units are packaged
and sealed on shipping skids and ship in first class condition. Report to the carrier any torn or
broken packaging, or scratched or dented panels.
Prior to installation, internally inspect all units. Remove all the access doors and check for visual
defects that can occur during transport. Any problems found internally should be immediately
reported to the carrier and the manufacturer. Check the refrigerant circuit to ensure no leaks have
occurred during shipment.
Install the gauge set to high and low pressure ports to confirm the pressure has been maintained
and no leaks have occurred during shipment. To ensure safe operation, repair any damage.
Note:
Record any unit damage on the Bill of Lading and report to carrier and factory
immediately. Shipping and handling damages are not warranty items.
WARNING
Prior to mounting unit, check individual unit weights (Table 1 on page 11) and verify lifting capacity of
lifting equipment exceeds weight of units by safe margins. Failure to do so may result in unit damage,
personal injury, or even death.
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Model DSH024C–120C Horizontal R-410A Air Conditioning Units C-Generation Smart Equipment Controller
Johnson Controls
