HOTSY • 900-1400 • 9.803-325.0-B OPERATOR MANUAL • GAS FIRED
15
PRESSURE W
ASHER
OPERA
TOR’S MANU
AL
98033250-7
OF
F
ON
Outlet View
On/Off
Switch
Manifold
Pressure Adjustment
Screw Under Cap
Illustration showing air openings necessary
to supply air for combustion when installed
in an enclosed room.
Figure 3: Ventilation
Type "B", due to its temperature rating, can only be
used with natural draft pressure washers. A "B" vent
is designed for exhaust temperatures not to exceed
470°F (245°C).
All venting installations must conform to local codes.
In the absence of local codes, refer to "National Fuel
Gas Code" NFPA 54 and be constructed of materials
approved by the Uniform Building Code.
Vents penetrating ceilings or walls should be double-
wall approved appliance vents and should be one to
two inches from combustibles. Vents passing through
enclosed spaces and vents exposed to the weather
should also be the double-wall type. Sometimes vents
have to be built of such great length that they come
apart at their joints under their own weight. These
should be screwed together at the joints with sheet
metal screws, usually three per joint. If the inspector
indicates that the vent is too close to combustibles, it
may be necessary to chisel away some of the com-
bustible or route the vent pipe around the combustible.
The cross-sectional area of any flue shall not be less
that the cross-sectional area of the flue vent connection
outlet of machine.
Water Source:
The water source for the machine should be supplied
by a 5/8" I.D. garden hose with a city water pressure of
not less than 30 PSI. If the water supply is inadequate,
or if the garden hose is kinked, the machine will run
very rough and the burner will not fire.
Water Connection:
Connect the high pressure hose by pulling the coupler
collar back and then inserting it onto the discharge
nipple. Secure it by pushing the collar forward.
Attach the wand into the spray gun using teflon tape
on the pipe threads to avoid leaks.
INSTALLATION INSTRUCTIONS
Inspection and Testing Gas Piping:
The building structure should not be weakened by
installing the gas piping. The piping should not be sup-
ported by other piping, but should be firmly supported
with gas hooks, straps, bands or hangers. Butt or lap
welded pipe should not be run through or in an air duct
or clothes chute.
Before turning gas under pressure into piping, all open
-
ings from which gas can escape should be closed.
Immediately after turning on gas, the system should
be checked for leaks. This can be done by watching the
1/2 cubic foot test dial for 5 minutes for any movement
or by soaping each pipe connection and watching for
bubbles. If a leak is found, make the necessary repairs
and repeat the above test.
Defective pipes or fittings should be replaced and not
repaired. Never use a flame or fire in any form to locate
gas leaks — use a soap solution.
After the piping and meter have been checked com-
pletely, purge the system of air.
DO NOT
bleed the air
inside an enclosed room.
During pressure testing of the system at test pressures
in excess of 1/2 PSIG, the pressure washer and its
individual shut-off valve must be disconnected from
gas supply piping system or damage to the gas valve
will occur.
Gas Pressure:
The ideal incoming gas pressure is 11 w.c.i (water
column inches). Minimum is 9 w.c.i., maximum is 14
w.c.i. or 1/2 PSIG. The correct operating manifold pres-
sure for natural gas is 2.8 w.c.i. The operating manifold
pressure for propane gas is 7.5 w.c.i.
By adjusting the
gas valve pressure regulator between 3 and 4 w.c.i. a
side range can be achieved for natural gas.
If the desired input rating cannot be obtained within the
above manifold pressure adjusting range, then the next
size larger or smaller burner orifice should be used.
