Notes:
• Dashed lines indicate provided by installer.
• The water supply inlet is more than 1” (25 mm) above the skim/overflow port, eliminating the possibility of backflow or siphoning from the chamber.
No additional backflow prevention is required; however, governing codes prevail.
Shock arrester
recommended to
reduce water hammer
Water supply line
Spill funnel;
plumb to
floor drain
1” (25 mm)
air gap
¾” (DN20) copper
chamber drain
and overflow
piping, rated for
140°F (60°C).
If piping run
is over 10’ (3 m)
increase pipe to
1¼” (DN32).
Open drain required. Locate air gap only in
spaces with adequate temperature and air
movement to absorb flash steam; otherwise,
condensing on nearby surfaces may occur.
Refer to governing codes for drain pipe size
and maximum discharge water temperature.
Install plumb
Steam hose
(maximum run 10’ [3 m])
OM-4010
Union by installer
¼” (DN8) compression
fitting on fill valve
connection to water
supply line; water
pressure must be between
25 psi and 80 psi
(175 kPa and 550 kPa);
water conductivity
minimum 100 µS/cm2;
fill valve has an integral
strainer
FIGURE 22 – Field Piping Overview Showing Hard Pipe Drain Connections25