Hotsy 790SS Service manual

8.914-355.0
SERIAL NUMBER:
DATE PURCHASED:
FOR SALES AND SERVICE, PLEASE CONTACT:
OPERATING INSTRUCTIONS
AND PARTS MANUAL
Read instructions carefully before attempting to assemble, install, operate or service this pressure
washer. Failure to comply with instructions could result in personal injury and/or property damage!
MODELS 790SS, 790SS-208,
795SS, 795SS-208, 895SS

790SS
●Pump Volume At Pump Head: 2.8 gpm/168 gph
●Pump Pressure At Pump Head: 2000 psi
●Burner Type: Fuel Oil Fired, 289,900 BTU/Hr.
●Burner Fuel Pressure: 140 psi
●Machine Voltage: 230Vac/60Hz/1Ph
●Total Machine Amperage: 20 Amps
●Machine Weight: 409 Lbs.
●Shipping Weight: 459 Lbs.
●Exhaust Stack Size: 8"
●Machine Dimensions:
Length = 51", Width = 29", Height = 42"
790SS-208
●Pump Volume At Pump Head: 2.8 gpm/168 gph
●Pump Pressure At Pump Head: 2000 psi
●Burner Type: Fuel Oil Fired, 289,900 BTU/Hr.
●Burner Fuel Pressure: 140 psi
●Machine Voltage: 208Vac/60Hz/1Ph
●Total Machine Amperage: 22 Amps
●Machine Weight: 409 Lbs.
●Shipping Weight: 459 Lbs.
●Exhaust Stack Size: 8"
●Machine Dimensions:
Length = 51", Width = 29", Height = 42"
795SS
●Pump Volume At Pump Head: 3.5 gpm/210 gph
●Pump Pressure At Pump Head: 2000 psi
●Burner Type: Fuel Oil Fired, 289,900 BTU/Hr.
●Burner Fuel Pressure: 140 psi
●Machine Voltage: 230Vac/60Hz/1Ph
●Total Machine Amperage: 24 Amps
●Machine Weight: 409 Lbs.
●Shipping Weight: 459 Lbs.
●Exhaust Stack Size: 8"
●Machine Dimensions:
Length = 51", Width = 29", Height = 42"
795SS-208
●Pump Volume At Pump Head: 3.5 gpm/210 gph
●Pump Pressure At Pump Head: 2000 psi
●Burner Type: Fuel Oil Fired, 289,900 BTU/Hr.
●Burner Fuel Pressure: 140 psi
●Machine Voltage: 208Vac/60Hz/1Ph
●Total Machine Amperage: 27 Amps
●Machine Weight: 409 Lbs.
●Shipping Weight: 459 Lbs.
●Exhaust Stack Size: 8"
●Machine Dimensions:
Length = 51", Width = 29", Height = 42"
895SS
●Pump Volume At Pump Head: 3.5 gpm/210 gph
●Pump Pressure At Pump Head: 3000 psi
●Burner Type: Fuel Oil Fired, 289,900 BTU/Hr.
●Burner Fuel Pressure: 140 psi
●Machine Voltage: 230Vac/60Hz/1Ph
●Total Machine Amperage: 36 Amps
●Machine Weight: 431 Lbs.
●Shipping Weight: 481 Lbs.
●Exhaust Stack Size: 8"
●Machine Dimensions:
Length = 51", Width = 29", Height = 42"

CONTENTS
4
8.914-355.0 • Rev. /11
Model Number ______________________________
Serial Number ______________________________
Date of Purchase ___________________________
The model and serial numbers will be found on a decal attached to the
pressure washer. You should record both serial number and date of
purchase and keep in a safe place for future reference.
Important Safety Information 5-7
Component Identification 8
Assembly Instructions 9
Installation Instructions 10
Operation Instructions 11
General Cleaning Techniques & Storage 12
Maintenance 13
Troubleshooting 14-15
Warranty

8.914-355.0 • Rev. 08/11A
5
PRESSURE WASHER
OPERATOR’S MANUAL
INTRODUCTION & IMPORTANT SAFETY INFORMATION
Thank you for purchasing this Pressure Washer.
We reserve the right to make changes at any time
without incurring any obligation.
Owner/User Responsibility:
The owner and/or user must have an understanding of
the manufacturer’s operating instructions and warnings
before using this pressure washer.Warning information
should be emphasized and understood. If the operator
is not fluent in English, the manufacturer’s instruc-
tions and warnings shall be read to and discussed
with the operator in the operator’s native language by
the purchaser/owner, making sure that the operator
comprehends its contents.
Owner and/or user must study and maintain for future
reference the manufacturers’ instructions.
The operator must know how to stop the machine
quickly and understand the operation of all controls.
Never permit anyone to operate the engine without
proper instructions.
This manual should be considered a permanent
part of the machine and should remain with it
if machine is resold.
When ordering parts, please specify model and
serial number. Use only identical replacement
parts.
This machine is to be used only by trained
operators.
IMPORTANT SAFETY
INFORMATION
READ OPERATOR’S
MANUAL THOROUGHLY
PRIOR TO USE.
WARNING:To reduce the risk of
injury, read operating instruc-
tions carefully before using.
1. Read the owner's manual
thoroughly. Failure to fol-
low instructions could cause
malfunction of the machine
and result in death, serious
bodily injury and/or property
damage.
2. Know how to stop the machine and bleed pressure
quickly. Be thoroughly familiar with the controls.
3. Stay alert — watch what you are doing.
4. All installations must comply with local codes.
Contact your electrician, plumber, utility company
or the selling distributor for specific details. If your
machine is rated 250 volts or less, single phase will
be provided with a ground fault circuit interrupter
(GFCI). If rated more than 250 volts, or more than
single phase this product should only be con-
nected to a power supply receptacle protected by
a GFCI.
DANGER: Improper connection of the equipment-
grounding conductor can result in a risk of elec-
trocution. Check with a qualified electrician or
service personnel if you are in doubt as to whether
the outlet is properly grounded. Do not modify the
plug provided with the product - if it will not fit the
outlet, have a proper outlet installed by a qualified
electrician. Do not use any type of adaptor with
this product
WARNING
KEEP WATER
SPRAY AWAY FROM
ELECTRICAL WIRING.
WARNING: Keep wand, hose, and
water spray away from electric
wiring or fatal electric shock may
result.
5. To protect the operator from
electrical shock, the machine
must be electrically grounded.
It is the responsibility of the
owner to connect this machine
to a UL grounded receptacle of proper voltage and
amperage ratings. Do not spray water on or near
electrical components. Do not touch machine with
wet hands or while standing in water. Always dis-
connect power before servicing.
RISK OF EXPLOSION:
OPERATE ONLY WHERE
OPEN FLAME OR TORCH
IS PERMITTED
WARNING
WARNING: Flammable liquids
can create fumes which can ig-
nite, causing property damage
or severe injury.
WARNING: Risk of explosion —
Operate only where open flame
or torch is permitted.
6. In oil burning models, use only kerosene, No. 1
home heating fuel, or diesel. If diesel is used, add
a soot remover to every tankful.
RISK OF FIRE.
DO NOT ADD FUEL
WHEN OPERATING
MACHINE.
WARNING
WARNING: Risk of fire — Do not
add fuel when the product is
operating or still hot.
WARNING: Do not use gasoline
crankcase draining or oil con-
taining gasoline, solvents or
alcohol. Doing so will result in
fire and/or explosion.
7. Oil burning appliances shall be installed only in
locations where combustible dusts and flammable
gases or vapors are not present. Do not store or
use gasoline near this machine.
8. Do not allow acids, caustic or abrasive fluids to pass
through the pump.
9. Never run pump dry or leave spray gun closed
longer than 1-2 minutes.
10. Keep operating area clear of all persons.

8.914-355.0 • Rev. 08/11A
OPERATOR’S MANUAL
PRESSURE WASHER
6
RISK OF INJECTION
OR SEVERE INJURY
TO PERSONS. KEEP
CLEAR OF NOZZLE.
WARNING
WARNING: High pressure de-
veloped by these machines will
cause personal injury or equip-
ment damage. Keep clear of
nozzle. Use caution when oper-
ating. Do not direct discharge
stream at people, or severe in-
jury or death will result.
WARNING
PROTECT FROM
FREEZING
WARNING: Protect machine from
freezing.
15. To keep machine in best
operating conditions, it is
important you protect machine
from freezing.Failure to protect
machine from freezing
could cause malfunction of the
machine and result in death,
serious bodily injury, and/or property damage. Fol-
low storage instructions specified in this manual.
16. Inlet water must be clean fresh water and no hotter
then 90°F.
WARNING
RISK OF
ASPHYXIATION: USE
THIS PRODUCT ONLY
IN A WELL
VENTILATED AREA.
WARNING: Risk of asphyxiation.
Use this product only in a well
ventilated area.
17. Avoid installing machines in
small areas or near exhaust
fans. Adequate oxygen is
needed for combustion or
dangerous carbon monoxide
will result.
18. Manufacturer will not be liable for any changes
made to our standard machines or any compo-
nents not purchased from us.
19. The best insurance against an accident is precau-
tion and knowledge of the machine.
WARNING
RISK OF INJURY FROM
FALLS WHEN USING
LADDER.
WARNING: Be extremely careful
when using a ladder, scaffolding
or any other relatively unstable
location. The cleaning area
should have adequate slopes
and drainage to reduce the pos-
sibility of a fall due to slippery
surfaces.
20. Do not overreach or stand on unstable support.
Keep good footing and balance at all times.
21. Do not operate this machine when fatigued or
under the influence of alcohol, prescription medi-
cations, or drugs.
IMPORTANT SAFETY INFORMATION
WARNING
USE PROTECTIVE
EYE WEAR
AND CLOTHING
WHEN OPERATING
THIS EQUIPMENT.
WARNING: High pressure spray
can cause paint chips or other
particles to become airborne
and fly at high speeds.To avoid
personal injury, eye, hand and
foot safety devices must be
worn.
11. Eye, hand, and foot protec-
tion must be worn when using
this equipment.
WARNING
EAR PROTECTION
MUST BE WORN
WARNING: This machine ex-
ceeds 85 db appropriate ear
protection must be worn.
WARNING
HOT DISCHARGE FLUID:
DO NOT TOUCH OR
DIRECT DISCHARGE
STREAM AT PERSONS.
WARNING: Hot discharge fluid.
Do not touch or direct discharge
stream at persons.
WARNING: This machine pro-
duces hot water and must have
insulated components attached
to protect the operator.
WARNING
RISK OF INJURY:
HOT SURFACES
CAN CAUSE BURNS
WARNING: Risk of injury. Hot
surfaces can cause burns. Use
only designated gripping areas
of spray gun and wand. Do not
place hands or feet on non-in-
sulated areas of the pressure
washer.
12. To reduce the risk of injury, close supervision is
necessary when a machine is used near children.
Do not allow children to operate the pressure
washer. This machine must be attended during
operation.
TRIGGER GUN KICKS
BACK - HOLD WITH
BOTH HANDS
WARNING
WARNING: Grip cleaning wand
securely with both hands be-
fore starting. Failure to do this
could result in injury from a
whipping wand.
13. Never make adjustments on
machine while in operation.
14. Be certain all quick coupler
fittings are secured before
using pressure washer.

8.914-355.0 • Rev. 08/11A
7
PRESSURE WASHER
OPERATOR’S MANUAL
IMPORTANT SAFETY INFORMATION
Follow the maintenance instructions
specified in the manual.

8.914-355.0 • Rev. 08/11A
OPERATOR’S MANUAL
PRESSURE WASHER
8
COMPONENT IDENTIFICATION
KEEP GUARD IN PLACE
ATALL TIMES
Pump — Delivers a specific gpm to the high pressure
nozzle which develops pressure.
Spray Gun — Controls the application of water and
detergent onto cleaning surface with trigger device.
Includes safety latch.
Detergent Injector — Allows you to siphon and mix
detergents.
Wand — Must be connected to the spray gun.
High Pressure Hose — Connect one end to water
pump high pressure discharge nipple and the other
end to spray gun.
Unloader Valve — Safety device which, when the
spray gun closes, prevents over pressurization (Not
Shown.)
Note:If trigger on spray gun is released for more
than 2 minutes, water will leak from the pump
protector. Warm water will discharge from pump
protector onto floor.This system prevents internal
pump damage.
High Pressure
Hose
Spray Gun
Wand
Detergent Line
Pump
Unloader
Valve
Hose Reel
Bracket
Pump
Switch
Burner
Switch
Adjustable
Thermostat
GFCI
Motor
Fuel
Oil Tank
High
Pressure Nozzle
Coil

8.914-355.0 • Rev. 08/11A
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PRESSURE WASHER
OPERATOR’S MANUAL
Bolts, Washers
and Flange Nut
Handle
Figure 3 - Handle Installation
Unpacking
Unpack carefully. Wear safety glasses or goggles while
unpacking, assembling or operating pressure washer.
If there are missing components or hidden damage
immediately contact distributor or carrier concerning
discrepancies.
1. Cut strapping band from pressure washer and pal-
let.
2. Remove pressure washer from pallet.
Parts Included
• Pressure Washer
• Pressure Hose/Trigger Gun Assembly
• Wand Assembly
• Handle
• Envelope Including:
■Bolt 5/16" - 18 x 2" (5 ea.)
■Flange Nut 5/16" - 18 (7 ea.)
■Flat Washer 5/16" (5 ea.)
■Operating Instructions/Parts Manual
Tools Required
• 10" Adjustable Crescent Wrench (2 ea.)
• Teflon Tape
Pressure Hose, Trigger Gun and Wand
1. Use teflon tape on plumbing connections to prevent
leakage.
2. Install pressure hose on machine as shown in
Figure 1.
3. Attach the wand assembly to the pressure hose/trigger
gun assembly as shown in Figure 2.
Handle
1. Remove plastic tubing from ends of handle.
2. Insert the handle through the holes in the chassis as
shown in Figure 3. Use the bolts, washers and nuts
from envelope to secure the handle to the chassis.
ASSEMBLY INSTRUCTIONS
Figure 1 - Pressure Hose Installation
Pressure
Hose
Relief Valve
Figure 2 - Wand/Trigger Gun Assembly
Wand
Assembly
Pressure Hose/
Trigger Gun Assembly

8.914-355.0 • Rev. 08/11A
OPERATOR’S MANUAL
PRESSURE WASHER
10
INSTALLATION INSTRUCTIONS
Getting Started
IMPORTANT: The use of a backflow preventer on
the water supply hose is recommended and may be
required by local code.
The pressure washer should be run on a level surface
where it is not readily influenced by outside sources
such as strong winds, freezing temperatures, rain, etc.
The pressure washer should be located to assure easy
access for filling of fluids, adjustments and maintenance.
Normal precautions should be taken by the operator to
prevent moisture from reaching the pressure washer. It
is recommended that a partition be made between the
wash area and the pressure washer to prevent direct
spray from the wand coming in contact with the pressure
washer. Moisture reaching the equipment will reduce the
pressure washer’s life. All installations should comply with
the local codes covering such installations.
Venting
CAUTION: All venting must be in accordance with ap-
plicable federal and state laws, and local ordinances.
Consult local heating contractors.
If the pressure washer is to be used in an enclosed area, a
flue must be installed to vent burner exhaust to the outside
atmosphere. Exhaust gases should not be vented into a
wall, a ceiling, or a concealed space of a building. Be sure
the flue is the same size as the burner exhaust vent on
the pressure washer. See Component Identification for
location. Poor draft will cause the pressure washer to soot
and not operate properly. When selecting the location for
installation, beware of poorly ventilated locations or areas
where exhaust fans may cause an insufficient supply of
oxygen. Proper combustion can only be obtained when
there is a sufficient supply of oxygen available for the
amount of fuel being burned. If it is necessary to install
the machine in a poorly ventilated area, outside fresh air
may have to be piped to the burner and a fan installed to
bring sufficient air into the machine. Locate the pressure
washer so that the flue will be as straight as possible and
protrude through the roof at a proper height and location
to provide adequate draft. This oil fired pressure washer
must have a draft regulator installed in the flue (available
from most heating contractors). A draft regulator will
permit proper upward flow of exhaust flue gases.
Oil Burner
Burner Air Adjustment: The oil burner is preset for
operation at altitudes below 1000 feet. If operated at
higher altitudes, it may be necessary to adjust the air band
setting. Adjust the air band for a #1 or #2 smoke spot on
the Bacharach scale.
To adjust, start machine and turn burner ON (refer to
Operation for details). Loosen two locking screws
found in the air shutter openings (refer to Figure 4) and
close air shutter until black smoke appears from burner
exhaust vent. Note air band position. Next, slowly open
the air shutter until white smoke just starts to appear.
Turn air shutter halfway back to the black smoke position
previously noted. Tighten locking screws.
If the desired position cannot be obtained using only the
air shutter, lock the air shutter in as close a position as
can be obtained, then repeat the above procedure on the
air band setting.
CAUTION: If white smoke appears from burner
exhaust vent during start-up or operation, discontinue
use and readjust air bands.
NOTE: If a flue is installed, have a professional ser-
viceman adjust your burner for a #1 or #2 smoke spot
on the Bacharach scale
.
For additional burner component information, see
. It is recommended that the oil burner be serviced
yearly or as needed. Contact your local service center.
Air Shutter
Locking Screw Air Shutter
Air Band
Air Band
Locking Screw
Air Shutter Locking
Screw
Figure 4 - Burner Air Band Adjustment

8.914-355.0 • Rev. 08/11A
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PRESSURE WASHER
OPERATOR’S MANUAL
OPERATION INSTRUCTIONS
Before Starting
WARNING: Check hoses, guns, fittings, and fuel
connections daily for signs of wear, cracks and
looseness, and replace as required.
1. Read all manuals provided with this pressure washer.
Become familiar with location and function of all
operating and safety controls.
2. Connect water supply hose to the standard garden
hose connector. The water faucet and supply hose
must be capable of providing 3.0 gpm for 790SS,
790SS-208 and 4 gpm for 795SS, 795SS-208.
3. Fill fuel tank. Use kerosene, #1 grade home heating
oil, #1 or #2 diesel fuel. DO NOT USE GASOLINE,
CRANKCASE OIL DRAININGS OR WASTE OIL.
4. Check pump oil level.
5. If detergents are to be used, only use detergents
intended for pressure washers. Follow instructions on
the detergent container.
Electrical Connections
WARNING: Make sure all switches and controls are
in the OFF position prior to plugging in.
CAUTION: This pressure washer is equipped with a
UL approved ground fault circuit interrupter (GFCI)
power cord. Use UL grounded type receptacles
of proper voltage and amperage ratings. Where a
properly grounded receptacle is not available, it is
the personal responsibility of the owner to have one
installed. Always disconnect power before servicing
your pressure washer.
Connect electrical cord and test the GFCI using the reset
and test procedures provided on the GFCI device. The
GFCI must be reset and tested with every use. Do not
use machine if the GFCI device fails test.
Nozzle Installation
IMPORTANT: Before installing nozzle on initial start-
up, turn on the water supply, and allow water to run
from the end of the wand until clear to prevent the
nozzle from clogging.
IMPORTANT: If the pressure washer has not been
used for an extended period of time, remove the
nozzle from the end of the wand and turn on water
supply. Allow water to run from the end of the wand
until clear.
1. Install the proper pressure nozzle for your cleaning
needs on the end of the wand. Refer to Figure 5.
IMPORTANT: The trigger gun provided with this pres-
sure washer is equipped with a manual trigger lock to
prevent accidental operation of the trigger gun; refer
to Figure 5.The trigger lock should be used whenever
the trigger gun is not in use.
To Start
IMPORTANT: The water must be turned on before
starting. Running the pump dry will cause damage
to pump seals and void warranty.
IMPORTANT: DO NOT allow the machine to run in
bypass for more than 10 minutes at any one time or
damage to pump may occur.
1. Turn water ON.
2. Hold gun firmly, squeeze trigger of trigger gun and turn
pump switch ON. Allow air to purge from system.
3. If HOT water is desired, turn burner switch ON.
Adjust thermostat to desired temperature.The burner
will fire immediately with a small puff of smoke. If
smoke continues refer to the Troubleshooting Guide
in this manual. When the trigger gun is closed the
burner will turn off.
To Stop
1. If detergents were used, draw clear water through the
detergent line to purge detergent.
2. If burner was used, turn off burner switch and allow
pump to run cold water through coil.
3. Turn pump switch OFF.
4. Turn OFF water supply.
5. Squeeze trigger gun open to relieve system pres-
sure.
Figure 5 - Nozzle Installation/Trigger Lock
Pressure Nozzle
Manual Trigger
Lock

8.914-355.0 • Rev. 08/11A
OPERATOR’S MANUAL
PRESSURE WASHER
12
CLEANING TECHNIQUES
Pre-rinse cleaning surface with fresh water. Place de-
tergent suction tube directly into cleaning solution and
apply to surface at low pressure (for best results, limit
your work area to sections approximately 6 feet square
and always apply detergent from bottom to top). Allow
detergent to remain on surface 1-3 minutes. Do not
allow detergent to dry on surface. If surface appears
to be drying, simply wet down surface with fresh water.
If needed, use brush to remove stubborn dirt. Rinse at
high pressure from top to bottom in an even sweeping
motion keeping the spray nozzle approximately 1 foot
from cleaning surface. Use overlapping strokes as you
clean and rinse any surface. For best surface cleaning
action spray at a slight angle.
Recommendations:
• Before cleaning any surface, an inconspicuous
area should be cleaned to test spray pattern and
distance for maximum cleaning results.
• If painted surfaces are peeling or chipping,
use extreme caution as pressure washer may
remove the loose paint from the surface.
• Keep the spray nozzle a safe distance from the
surface you plan to clean. High pressure wash a
small area, then check the surface for damage. If
no damage is found, continue to pressure wash-
ing.
CAUTION - Never use:
• Bleach, chlorine products and other corrosive
chemicals
• Liquids containing solvents (i.e., paint thinners,
gasoline, oils)
• Tri-sodium phosphate products
• Ammonia products
• Acid-based products
These chemicals will harm the machine and will dam-
age the surface being cleaned.
GENERAL CLEANING TECHNIQUES & STORAGE
RINSING
It will take a few seconds for the detergent to clear.
Apply safety latch to spray gun. Select and install de-
sired high pressure nozzle. NOTE: You can also stop
detergent from flowing by removing detergent siphon
tube from bottle.
STORAGE
DANGER: DO NOT store flammable liquids (gasoline,
diesel fuel, solvents, etc.) near pressure washer, or in
non-ventilated areas.
Protect from freezing by storing in a heated area, or by
flushing the system with antifreeze (use an automotive
engine antifreeze or windshield washer solvent to
antifreeze). To flush the system with antifreeze, attach
a short length of hose to the garden hose connector
located on the pump. Place the other end of the hose
into a container of antifreeze. Start machine and allow
to run until antifreeze flows from the end of the wand.
Squeeze and release the trigger of the trigger gun several
times to antifreeze the unloader system. Also draw
antifreeze through the detergent inlet line to antifreeze the
detergent system. For added protection after anti-freezing,
disconnect the pressure hose from machine and remove
the coil drain plug (refer to Component Identification for
location). After coil has drained, replace pressure hose
and coil drain plug. If the pressure washer is not to be used
for an extended length of time, it is recommended that the
system be flushed with antifreeze for rust protection.

8.914-355.0 • Rev. 08/11A
13
PRESSURE WASHER
OPERATOR’S MANUAL
MAINTENANCE
WARNING: Unauthorized machine modification or
use of non-approved replacement parts may cause
personal injury and/or property damage and will void
the manufacturer warranty.
Pump
Lubrication: To lubricate pump, use 30W non-detergent
oil for pump crankcase. Crankcase must be filled to center
of sight glass window found on the side of the pump; refer
to Figure 6. During the break-in period, make sure the
oil is changed after the first 25 hours of operation. After
that, replace oil every 3 months or 300 hours of operation,
whichever comes first.
Proper Pump Care:
• DO NOT pump acids.
• DO NOT allow pump to run dry.
• Winterize if storing in freezing temperatures. Refer
to Storage for details.
• Use a water softener on the water system if known
to be high in mineral content.
• Use only high quality detergents and follow manu-
facturer’s mix recommendations.
• Flush the system with clear water immediately
after using detergent solutions.
• Clean filter screen on detergent inlet line periodi-
cally.
• Flush the pressure washer system with antifreeze
if storing for an extended period of time, refer to
Storage for details.
Pump Motor
On a yearly basis, oil pump motor per instructions on
motor nameplate.
Relief Valve
WARNING: The relief valve on this pressure washer
has been factory set and sealed and is a field non-
adjustable part. Tampering with the factory setting
may cause personal injury and/or property damage,
and will void the manufacturer warranty. For replace-
ment parts refer to Coil Outlet Assembly .
If pressure from pump or thermal expansion should
exceed safe limits, the relief valve will open, allowing
high pressure to be discharged through hose to ground.
Caution: Inspect relief valve annually for any obstruc-
tion .
Unloader Valve
WARNING: The unloader valve on this pressure
washer has been factory set and sealed and is a field
nonadjustable part.Tampering with the factory setting
may cause personal injury and/or property damage,
and will void the manufacturer warranty. For replace-
ment refer to Pump Assembly.
Burner Fuel Filter
Drain any water which has accumulated in fuel filter and
clean or replace element as needed. For replacement
parts, refer to Burner Assembly.
Heating Coil
Coil Descaling: In hard water areas, scale buildup within
the heating coil will occur. Scale deposits will decrease
the water temperature rise and may eventually clog the
heating coil. Contact your local service center when
descaling is needed.
Coil Desooting: Poor grades of fuel oil or inadequate
combustion air will cause heavy soot buildup on the
outside surface of the heating coil. These deposits will
insulate the coil. This will restrict the air flow through the
coil, further aggravating the soot buildup. Contact your
local service center when desooting is needed.
Figure 6 - Pump Lubrication
Oil Fill/Dip Stick
Sight
Glass
Oil Drain

8.914-355.0 • Rev. 08/11A
PRESSURE WASHER Troubleshooting Guide
14
TROUBLESHOOTING
SYMPTOM POSSIBLE CAUSES CORRECTIVE ACTION
PUMP MOTOR WILL
NOT RUN.
GFCI tripped. Reset and test GFCI with every use. Follow
Instructions under Operation.
No voltage to machine. Test power supply and correct.
Pump motor reset button (thermal
overload protector) tripped.
Push reset button on control box. If tripped,
check for proper voltage or clogged water
nozzle.
Excessive pressure due to clogged
water nozzle.
Clean water nozzle.
NO WATER SPRAYS
FROM WATER
NOZZLE.
Water nozzle completely clogged. Clean water nozzle.
Inlet water screen clogged. Check screen and clean if necessary.
Pump sucking air. Fill the detergent container and check for
loose hose clamps or fittings.
LOW PRESSURE
FROM WATER
NOZZLE.
Inlet water screen clogged. Check screen and clean if necessary.
Water nozzle worn or incorrect size. Replace nozzle with proper size.
Water supply low. Correct water supply.
Pump sucking air. Fill the detergent container and check for
loose hose clamps or fittings.
POOR OR NO
DETERGENT FLOW.
Low detergent level. Fill the detergent container.
Detergent screen clogged. Clean if necessary.
Detergent valve not opening. Check that handle or knob is not slip-ping
on shaft.
Water nozzle clogged. Clean water nozzle.
Excessive inlet pressure
(more than 80 PSI).
Install pressure regulator on the inlet line.
BURNER WILL
NOT IGNITE WHEN
TRIGGER GUN
IS OPEN.
Defective pressure switch. Replace pressure switch.
No fuel. Fill fuel tank with proper fuel.
Fuel valve closed. Check that fuel valve on fuel tank is open.
Thermostat set too low. Raise thermostat setting.
Burner motor reset button (thermal
overload protector) tripped.
Push reset button on burner motor. If
tripped, check for proper voltage.
Clogged fuel filter. Clean fuel filter.
BURNER SMOKES
OR HAS
OBNOXIOUS ODOR.
Air intake adjustment needs to be
adjusted.
Readjust air intake per the oil burner section
of this manual.
Improper fuel. Use proper fuel.

8.914-355.0 • Rev. 08/11A
15
PRESSURE WASHER Troubleshooting Guide
TROUBLESHOOTING
When ordering from your dealer, please provide the following:
Model Number: 790SS
Machine Serial Number: ________________________________
Component Part Number: _______________________________
Description: __________________________________________
IMPORTANT
If the pressure washer demonstrates other symptoms or the corrective actions
listed do not correct the problem, contact the local authorized Hotsy Service
Center. The Hotsy Service Center can be identified by visiting www.hotsy.com.

8.914-355.0 • Rev. 08/11A
PRESSURE WASHER WARRANTY
HOTSY LIMITED NEW PRODUCT WARRANTY
PRESSURE WASHERS
WHAT THIS WARRANTY COVERS
All Hotsy pressure washers are warranted by Hotsy to the original purchaser to be free from defects in materials and work-
manship under normal use, for the periods specified below. This Limited Warranty is subject to the exclusions shown below,
is calculated from the date of the original purchase, and applies to the original components only. Any parts replaced under
this warranty will assume the remainder of the part’s warranty period.
SEVEN YEAR PARTS AND ONE YEAR LABOR WARRANTY:
Components manufactured by Hotsy, such as frames, handles, top and bottom wraps, float tanks, fuel tanks, belt guards, and
internal components on the oil-end of HOTSY manufactured pumps. General, AR, Liberty, Comet and swash and wobble
plate pumps have a one year warranty. Heating coils have a five year warranty from date of original machine purchase.
ONE YEAR PARTS AND ONE YEAR LABOR WARRANTY:
All other components, excluding normal wear items as described below, will be warranted for one year on parts and
labor. Parts and labor warranty on these parts will be for one year regardless of the duration of the original component
manufacturer’s part warranty.
WARRANTY PROVIDED BY OTHER MANUFACTURERS:
Motors, generators, and engines, which are warranted by their respective manufacturers, are serviced through these manu-
facturers’ local authorized service centers. Hotsy is not authorized and has no responsibility to provide warranty service
for such components.
WHAT THIS WARRANTY DOES NOT COVER
This warranty does not cover the following items:
1. Normal wear items, such as nozzles, spray guns, discharge hoses, wands, quick couplers, seals, filters, gaskets,
O-rings, packings, pistons, pump valve assemblies, strainers, belts, brushes, relief valves, fuses, pump protec -
tors.
2. Damage or malfunctions resulting from accidents, abuse, modifications, alterations, incorrect installation, improper
servicing, failure to follow manufacturer’s maintenance instructions, or use of the equipment beyond its stated us-
age specifications as contained in the operator’s manual.
3. Damage due to freezing, chemical deterioration, scale build up, rust, corrosion, or thermal expansion.
4. Damage to components from fluctuations in electrical or water supply.
5. Normal maintenance service, including adjustments, fuel system cleaning, and clearing of obstructions.
6. Transportation to service center, field labor charges, or freight damage.
WHAT YOU MUST DO TO OBTAIN WARRANTY SERVICE
In order to obtain warranty service on items warranted by Hotsy, you must return the product to your Authorized Hotsy
Distributor, freight prepaid, with proof of purchase, within the applicable warranty period. If the product is permanently
installed, you must notify your Authorized Hotsy Distributor of the defect. Your Authorized Hotsy Distributor will file a claim
with Hotsy, who must subsequently verify the defect. In most cases, the part must be returned to Hotsy freight prepaid
with the claim. For warranty service on components warranted by other manufacturer’s, your Authorized Hotsy Distributor
can help you obtain warranty service through these manufacturers’ local authorized service centers.
LIMITATION OF LIABILITY
Hotsy’s liability for special, incidental, or consequential damages is expressly disclaimed. In no event shall Hotsy’s liability
exceed the purchase price of the product in question. Hotsy makes every effort to ensure that all illustrations and specifica-
tions are correct, however, these do not imply a warranty that the product is merchantable or fit for a particular purpose, or
that the product will actually conform to the illustrations and specifications. Our obligation under this warranty is expressly
limited at our option to the replacement or repair at a service facility or factory designated by us, of such part or parts as
inspection shall disclose to have neen defective. THE WARRANTY CONTAINED HEREIN IS IN LIEU OF ALL OTHER
WARRANTIES, EXPRESS OR IMPLIED, INCLUDING ANY IMPLIED WARRANTY OF MERCANTABILITY OR FITNESS
FOR A PARTICULAR PURPOSE ARE EXPRESSLY LIMITED TO THE DURATION OF THIS WRITTEN WARRANTY.
Hotsy does not authorize any other party, including authorized Hotsy Distributors, to make any representation or promise
on behalf of Hotsy, or to modify the terms, conditions, or limitations in any way. It is the buyer’s responsibility to ensure that
the installation and use of Hotsy products conforms to local codes. While Hotsy attempts to assure that its products meet
national codes, it cannot be responsible for how the customer chooses to use or install the product. Some states do not al-
low limitations on how long an implied warranty lasts or the exclusion or limitation of incidental or consequential damages,
so the above limitation or exclusion may not apply to you. This warranty gives you specific legal rights and you may also
have other rights which vary from state to state.
HOTSY
www.hotsy.com

If you are looking for replacement parts for your Hotsy, please contact your local dealer. You
can nd a dealer by calling Hotsy at 800-525-1976 or by visiting www.hotsy.com.

Form #8.914-355.0 • Revised 08/11A • Printed in U.S.A or México.
If you need service on your pressure washer, contact your local Hotsy
dealer or visit www.Hotsy.com. Smart phone users scan the code below to
link directly to the Service Request page.