Trane SCWH Air Conditioner User Manual


 
PKG-SVX14A-EN 17
mechanical
requirements
Duct Connections
Install all air ducts according to the
National Fire Protection Association
standards for the “Installation of Air
Conditioning and Ventilation Systems
other than Residence Type (NFPA 90A)
and Residence Type Warm Air Heating
and Air Conditioning Systems (NFPA
90B).
Make duct connections to the unit with a
flexible material such as heavy canvas. If
a fire hazard exists, Trane recommends
using Flexweave 1000, type FW30 or
equivalent canvas. Use three inches for
the return duct and three inches for the
discharge duct. Keep the material loose
to absorb fan vibration.
Run the ductwork straight from the
opening for a minimum of three fan
diameters. Do not make abrupt turns or
transitions near the unit due to increased
noise and excessive static losses. Use
elbows with splitters or turning vanes to
minimize static losses.
Poorly constructed turning vanes may
cause airflow generated noise. Check
total external static pressures against fan
characteristics to be sure the required
airflow is available throughout the
ductwork.
WARNING
Hazardous Voltage!
Disconnect all electric power,
including remote disconnects before
servicing. Follow proper lockout/
tagout procedures to ensure power
cannot be inadvertently energized.
Failure to disconnect power before
servicing could result in death or
serious injury.
Water Piping
Condenser Connections
Note: To prevent water damage, install
piping drain and vent plugs.
Condenser water piping knockouts are in
the lower left end panel. If necessary,
remove insulation to gain access. All field
installed piping must conform to
applicable local, state, and federal codes.
To complete condenser water
connections follow the procedure below.
1. Remove back panel to access the
water connection fittings.
2. Attach the water supply line to the inlet
connection, and the return line to the
outlet connection. The water connection
fittings are copper, so exercise extreme
care when connecting steel piping to
copper fittings.
3. Ensure that water piping is aligned to
the unit connection fittings. Failure to
align piping could cause stripped
threads, leakage, and possible unit
failure.
4. Connection to the unit water piping
requires a backing wrench to prevent
distortion of connecting tubing. Apply
backing wrench to water connection
points on unit.
Condensate Drain Connections
Install a water regulating valve in the
water supply line to maintainhead
pressure when operating with city water
of varying temperature.
These units require a minimum water
pressure of 15 psig and will operate at a
maximum of 400 psig.
Provide safeguards against cold weather
drain line freeze.
Installation
Cooling Tower Piping
Cooling tower control affects the unit
cycle rates. Condenser water
temperature swings from 10-15°F may
cause excessive compressor, water
valve, and unit cycling. Be sure to set the
tower controls to minimize compressor/
unit cycling.
The cooling tower system requires a
separate drain in the water supply line for
service and repair.
Water Temperature Requirements
Install a water regulating valve in the
water supply line to maintain head
pressure when operating with water of
varying temperature. The valve
modulates condenser water flow to
control condensing pressure. The valve
opens or closes in response to
compressor discharge pressure as
sensed by its capillary line connection iin
the liquid line shrader valve. When the
valve is properly installed, water flow
automatically decreases as discharge
pressure falls and increases as discharge
pressure rises. Field installation of the
water regulating valve assembly
requires one valve for each refrigeration
circuit.