SCXF-SVX01B-EN
23
Mechanical
Requirements
Water Piping
Note: To prevent water damage, install all
piping drain and vent plugs. See Figure I-
MR-2.
Condenser Connections
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.
Note: Four condenser waterline drain
plugs ship in a bag in the unit’s left end.
The installer must field install these four
plugs using pipe thread sealer. An addi-
tional plug iare provided for units with a
waterside economizer.
1. Install the vent plugs in the economizer
coil headers and condenser manifolds.
Refer to Figure I-MR-2. These plugs ship
in a bag with the condenser drain plugs.
2. Attach the water supply line to the inlet
connection, and the return line to the
outlet connection. Entering and leaving
water connections for all condensers
are factory manifolded and require only
single connections for entering and
leaving water. If the unit has a
waterside economizer and/or control
valves, the factory pipes between these
components.
3. If using a cooling tower, refer to Figure
I-MR-3 on page 24 for a typical piping
circuit from the unit. For typical city or
well water piping, see Figure I-MR-4 on
page 24.
4. Ensure the water pressure to the unit
does not exceed 400 psig.
Note: To prevent water pump damage,
design system piping to provide relief
when using energy saving waterside
economizer valves.
Figure I-MR-2. Economizer coil vent and condenser cleanout/drain plugs.
Installation
Condensate Drain Connections
The condensate drain is internally
trapped. Condensate drain connections
are on the unit’s left side. Connect
condensate drain piping to the 1
1
/
4
“ NPT
female fitting, using at least
7
/
8
” OD
copper or
3
/
4
“ OD iron pipe. Pitch the
condensate line downward a minimum of
1
/
2
” for each 10' of horizontal run, away
from the unit. Be sure to install the
condensate drain “P” trap drain plug.
Before starting the unit, fill the trap with
water to prevent negative pressure in the
fan section from impeding condensate
flow. To facilitate drain pipe cleaning,
install plugged tees in place of 90°elbows.
General Waterside Recommendations:
Cooling Towers
Cooling tower control affects the unit
cycle rates. Condenser water
temperature swings from 10-15 degrees
F may cause excessive compressor,
water valve, and unit cycling. Be sure to
set the tower controls to minimize
compressor/unit cycling.
Waterside Piping Arrangements
Install a condenser water pump between
the cooling tower (either open or closed)
and the self-contained unit. Lay out the
remainder of the system’s condenser
piping in reverse returns. This helps
balance the system by equalizing the
length of supply and return pipes.
Multistory buildings may use a direct
return system with balancing valves at
each floor.
Install the supply riser and its return in
close proximity. Furnish both with
permanent thermometers to check the
waterside balance during start-up and
routine maintenance checks.
Also, include strainers at each pump inlet
and unit. Install drain valves at the riser’s
base to allow drainage points for system
flushing during start-up and routine
maintenance. For condenser draining
and header removal, include a shutoff/
balancing valve on the entering and
leaving waterside pipes, drain tees, and
unions of each unit. Also, install a shutoff
valve on the unit entering water pipe for
condenser draining.
Note: Unit does not have floor drains.
