19
Operations
Size the stack according to the following (see also
applicable local and national standards regarding
installation of gas-fired appliances):
•
3.5 to 4.4 gpm 10” Collar 8” Stack
•
4.5 to 5.5 gpm 10” Collar 10” Stack
•
6.3 gpm 12” Collar 10” Stack
•
8 – 10 gpm 12” Collar 12” Stack
Draft Diverter/Hood
The draft required to vent
combustion gases is created by the heat inside the
pressure washer coil. A draft diverter helps improve
draft into the stack without pulling more air through the
combustion box and decreasing combustion efficiency.
The draft diverter can also help prevent back drafting
that can inhibit combustion. The draft diverter should be
installed a minimum of 36” above the flue collar.
Power Vent (Draft Inducer)
If this machine is going to
be installed on a 90° or extended exhaust vent run
length which may restrict air flow it is recommended
that a contractor install a power vent. When a
contractor has found it impossible to vent straight
through the roof power venting is recommended to help
eliminate exhaust restriction of this natural draft
machine. This draft inducer (power vent) must be
installed by a licensed contractor who can calculate
size, operation connections and associated damp-
eners. Since we are a manufacturer and not a licensed
contractor and as such we are unable to make recom-
mendations for suitable make and model of power
vents and compliance with local building codes.
Damper
An exhaust stack can reduce thermal effi-
ciency by drawing in too much combustion air. This can
be controlled by adding a damper just below the draft
diverter. 8.753-473.0 - 8" Damper, 8.753-474.0 -10"
Damper, 8.753-418.0 - 12" Damper.
NOTE: Closing the damper can create high levels of
CO in the exhaust. Adjustments to the damper should
only be performed by a trained technician using a flue
gas analyzer. If an analyzer is not used the damper
should be set in the fully open position.
Sampling Port
A port for sampling flue gases and
measuring the flue gas temperature should be placed
18” above the flue collar. The port should be covered
when sampling is not being performed. The size of the
port should be only slightly larger than the probe for the
flue gas analyzer.
Rain Cap
A rain cap should be installed on top of the
stack to prevent rain water, leaves and debris from
entering the stack. Your installer may also recommend
specialty caps for high wind areas or cold weather
zones to help prevent back drafting. 8.717-731.0 - 10"
Raincap, 8.717-732.0 - 12" Raincap
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.
Inspection and Testing Gas Piping
The building structure should not be weakened by
installing the gas piping. The piping should not be
supported 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
openings 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
completely, 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 indi-
vidual shut-off valve must be disconnected from gas
supply piping system or damage to the gas valve will
occur.
MANUAL, OPERATOR, HOTSY, STAT ELEC NG-LP 9.808-037.0-A
Draft Diverter
Required
8
.717-72
8
.0
8
"
9.
8
01-040.0 10"
8
.717-7
3
0.0 12"
