Fulton Pulse DWH (PDWH) Domestic Water Heater - Manual (Page 18)

Air supply is on the top. See Figure 6.
For Models PDWH750 & PDWH1000,
the connections are 4" NPT thread female
fittings. These fittings will accept 3" and
4" male/female pipe to tubing adaptors
respectively. This line must be sloped
down toward the unit with a pitch of at
least
1 /
4
" per foot. Failure to do so can
result in a condensate pocket which can
result in an inoperative water heater. A
high spot is acceptable, provided the
pitch from the high spot is maintained
back to the water heater and to the
outside point of air intake.
The air intake must be piped out of the
building. Air Intake pipes and fittings for
all models shall be Schedule 40 PVC
pipe. All Schedule 40 PVC pipe, fittings,
primer and solvent cement must
conform with American National
Standard Institute and the American
Society for Testing and Materials
(ANSI/ASTM standards.)
NOTE
Intake PVC piping must be assembled
using cement. This will ensure that the
intake is air tight and will not allow
contaminates from the water heater
room into the water heater. The solvent
shall be free flowing and contain no
lumps, undissolved particles or any
foreign matter that adversely affects the
joint strength or chemical resistance of
the cement. The cement shall not show
gelation, stratification, or separation that
cannot be removed by stirring.
WARNING
Solvent cements for plastic pipe are
flammable liquids and should be kept
away from all sources of ignition. Proper
ventilation should be maintained to
reduce the hazard and to minimize
breathing of solvent vapors. Avoid
contact of cement with skin and eyes.
The following procedure for cementing
joints (per ASTM D2855) should be
adhered to:
Step 1
Measure and cut PVC pipe to desired
Iength.
Step 2
Chamfer end of pipe, removing any
ridges or rough edges. If end is not
chamfered, the edge of the pipe may
remove cement from the fitting socket
and result in a leaking joint.
Step 3
Clean and dry surfaces to be joined.
Step 4
Test fit joint and mark depth of fitting on
pipe outside.
Step 5
Uniformly apply liberal coat of primer to
inside socket surface of fitting and male
end of pipe to depth of fitting socket.
Step 6
Promptly apply solvent cement to end of
pipe and inside socket surface of fitting.
Cement should be applied lightly—but
uniformly—to inside of socket. Take
care to keep excess cement out of
socket. Apply second coat to pipe end.
NOTE
Time is critical at this stage. Do not allow
primer to dry before applying cement.
Step 7
Immediately after applying last coat of
cement to pipe, while inside socket sur-
face and end of pipe are wet with cement,
insert end of pipe into socket, turn pipe
1 /
4
turn to distribute cement evenly, continue
to insert pipe until it bottoms out.
NOTE
Assembly should be completed within
20 seconds after last application of cem-
ent. Do not use hammer to insert pipe.
Step 8
After assembly, wipe excess cement
from pipe at end of fitting socket. A
properly made joint will show a bead
around its entire perimeter. Any gaps
may indicate a defective assembly due
to insufficient cement.
Step 9
Handle joints carefully until completely set.
Intake Muffler
Installation -
Figure 7
Follow steps 1-9 above for cementing
joints. For best noise attenuation, the
muffler should be installed as close to
the water heater as possible.
Installation
Figure 6
Air Intake Supply Piping
Installation Preparation
The water heater is equipped with air
intake supply and exhaust vent
connections located at the top and rear
of the water heater.
16-PDWH
Air Intake
Water Heater
Connection
Pipe-to-Tubing
Adapter
Schedule
40 PVC Pipe