Hotsy 555 HE User manual

9.808-216.0 English Rev B (01/21) 1
555 HE
Service Manual

9.808-216.0 English Rev B (01/21) 2
Preface
Safety instrucons
Hazard levels
Descripon in this service manual
Service groups
Technical Features
Intended use
Field of applicaon
Safety installaons
Connecon performance of appliance
Pump
Safety catch
Unloader / bypass valve
Thermal relief valve
Symbols on the machine
Type plate
Flow paern
Overview of the appliance
Callouts 555 HE
Pump overview
Pump head overview
Pump head cross secon overview
Pump breakdown overview
Unloader / Bypass valve overview
Thermal relief valve overview
Fuel pump
High-eciency burner
Fuel nozzle
Burn head assembly
Measure fuel consumpon (only for California)
Service group
Scheduled maintenance chart
Trouble shoong chart
Trouble shoong process
Understanding the dierence between low, cavitaon and pulsang pressure
Pulsaon
Contents
5
5
5
6
6
6
6
6
6
6
6
7
7
7
7
7
8
9
9-10
11
11
11
12
13
13
14
14
15
15
15
16
16
17
18
18
18

9.808-216.0 English Rev B (01/21) 3
Cavitaon
Low pressure
Replacing leaking thermal relief valve
Vibraon
Water leaking from under pump
Oil is leaking from under pump
Oil is milky
Pressure washer unloader cycles when trigger or spray bar trigger is released
Motor will not turn on
Machine shuts o aer running a while
No burner
Burner motor turns on but there is no ame—fuel
Raw fuel out of burner exhaust
Burner ame turns on but low water temperature
Water temperature is too hot
Scheduled maintenance acvies
Inspecng pump oil
Changing pump oil
Changing quick connects / O-rings
Burner fuel lter—drain water / clean / replace
Cleaning hard water deposits from heang coils
Cleaning soot deposits from heang coils
Fuel nozzle replacement
Trouble shoong acvies
Check valve inspecon / replacement
Inspect packings, ceramic pistons and connecng rod connecon
Inspect inlet screen
Bypass thermal protector
Test pressure at trigger gun
Test pressure o the machine
Test pressure o the coil outlet
Test pressure before the coil inlet
Test pressure o the unloader
Test pressure o the pump (bypassing the unloader)
Changing and seng the unloader
Contents
19
19
19
20
20
20
20
21
21 –22
22
22
23—24
24
24
24
25
25
25
25
26
26
27-28
29
30
30
31
32
32
33
33
33
34
34
35
35

9.808-216.0 English Rev B (01/21) 4
Inspecng side of pump for oil leak
Inspecng cranksha cap side of pump for oil leak
Inspecng piston guide oil seals for oil leak
Inspecng trigger gun for leak
Tesng power supply
Reset GFCI
Check to see if voltage is into the machine from power supply
Check voltage into the pump switch
Check voltage out of the pump switch
Check voltage into the overload
Check voltage out of the overload to the contactor coil
Check voltage into the contactor coil
Check voltage out of the contactor
Check voltage out of the overload to the motor
Check voltage at the motor
Check voltage into the burner switch
Check voltage out of the burner switch
Check to see if the burner motor is spinning
Check fuel pressure
Adjusng fuel pressure
Check voltage at fuel solenoid
Determining if the fuel solenoid needs replacing
Checking power out of the thermostat
Checking power into the thermostat
Check voltage into the pressure switch
Checking for spark
Adjusng air
Technical documentaon
Technical specicaons 555 HE
Tools required
Torque specicaons
Contents
36
36
37
37
38
38
38
38
39
39
39
39
40
40
40
40
41
41
41
41
42
42
42
42
43
43
43
44
44
45-48
49

9.808-216.0 English Rev B (01/21) 5
Good service work requires extensive and pracce-oriented
training as well as well-structured training materials. Hence we
oer regular basic, advanced and expert training programs
covering the enre product range for all cered distributor
technicians. In addion to this, we also prepare service manu-
als for important appliances—these can be inially used as
instrucon guides and later on as reference guides. Apart from
this, we oer regular informaon about product enhance-
ments and their servicing.
If you should require addional assistance, have correcons or
quesons regarding this document, please do not hesitate
contacng us at: www.Hotsy.com and click on customer feed-
back to enter any info you may have for us or you can also
contact any of our Technical Support Specialists at 800-220-
5409.
Copying and duplicaon of texts and diagrams as well as
third-party access to this informaon is permied only with
the explicit permission of the company: KARCHER NORTH
AMERICA 6398 N Kärcher Way, Aurora, CO 80019.
1Preface
Service and maintenance tasks may only be performed
by qualified and specially trained specialists.
Observe safety information in the chapters!
DANGER
Please read the operating instructions for your
machine before using it, and pay particular attention to
the following safety instructions.
Warning and information plates on the machine
provide important directions for safe operation.
Apart from the notes contained herein, the gen-
eral safety provisions and rules for the prevention of acci-
dents of the legislator must be observed.
Switch off the appliance and, in case of applianc-
es connected to mains, pull out the power cord before
cleaning and performing any maintenance tasks on the
machine.
Relieve the high pressure system of all pressure
prior to all work on the appliance and the accessories.
Only use accessories and spare parts which have
been approved by the manufacturer. The exclusive use of
original accessories and original spare parts ensures that
the appliance can be operated safely and trouble free.
Only use the fuels specified in the Operations
Manual. Risk of explosion due to the use of inappropriate
fuels.
In petrol engine appliances, ensure that no petrol
comes in contact with hot surfaces.
Ensure that there is adequate ventilation or provi-
sion for diverting the exhaust gas while operating the ap-
pliance in closed rooms (risk of poisoning).
Do not close the exhaust.
Please ensure that there are no exhaust emis-
sions near the air inlets.
Do not use high pressure cleaners when there
has been an oil spill; move the appliance to another spot
and avoid any sort of spark formation.
Do not store, spill or use fuel in the vicinity of
open flames or appliances such as ovens, boilers, water
heaters, etc. that have an ignition flame or can generate
sparks.
Do not use unsuitable fuels, as they may be dan-
gerous.
Keep even mildly inflammable objects and mate-
rials away from the muffler (at least 2 m).
Warning
Do not bend over the exhaust or touch it.
2Safety instrucons
2.1 Hazard levels
DANGER
For an immediate danger which can lead to severe injuries or
death.
WARNING
For a possibly dangerous situaon which could lead to severe
injuries or death.
CAUTION
For a possibly dangerous situaon which can lead to minor
injuries or property damage.
ATTENTION
Pointer to a possibly dangerous situaon, which can lead to
property damage.

9.808-216.0 English Rev B (01/21) 6
Example: Remove/install ANRA wheel axle
3 Descripon in this service manual
3.1 Service groups
AN RA Remove/install wheel axle
Service group Component Acvity
4Technical Features
High performance burner with upright heang coil
High limit hot water safety cut o
3-piston cranksha pump, piston with ceramic sleeves
Pump head made of brass
Sucon and high-pressure valves made of stainless steel
Unloader / bypass valve
Trigger gun
Single wand spray lance
3 power nozzles
Compact frame
Flat free res
4.1 Intended use
Mobile hot water high-pressure cleaner in various perfor-
mance classes for commercial use.
4.2 Field of applicaon
This service manual describes the following appliance:
Appliance type Appliance no. Operating instructions Spare parts list
555 HE 1.109-137.0 9.808-140.0 Available in DISIS
4.3 Safety installaons
Safety devices serve to protect the user and must not be
rendered in operational or their functions bypassed. Observe safety information in the chapters!
4.4 Connecon performance of appliance
20 Amp (555 HE).
4.5 Pump
3 piston direct drive pump with ceramic pistons
Cylinder head made of cast iron with special “HR” coating
Working pressure: 1300 psi
Water quantity: 2.2 gpm

9.808-216.0 English Rev B (01/21) 7
The safety catch on the trigger gun prevents the appli-
ance from being switched on unintentionally.
4.6 Safety catch
4.7 Unloader / bypass valve
4.8 Thermal relief valve
If the hand trigger bar or trigger gun is closed, the unload-
er / bypass valve opens and the entire water volume will
flow back to the suction side of the pump.
The unloader / bypass valve is set by the manufacturer
and sealed. Setting should only be performed by trained
technical service personnel.
The thermal relief valve helps to protect the high-pressure
pump from unacceptable heating during released trigger
operation.
4.10 Type plate
The type plate is located on the burner coil wrap.
1. Code consisting of 2 digit for week and 2 digit for year
machine was manufactured.
2. Bar code consisting of part number and serial number.
3. Code consisting of part number—serial number.
4.9 Symbols on the machine
Hot items, caution could burn or melt skin or material.
Disconnect from electrical supply before servicing.
Read operator’s manuals for both this unit and the attached machine before operating. This ma-
chine to be used only by qualified operators. High pressure developed by the machine attached to
this unit can cause personal injury. Use caution when operating. Do not direct discharge stream at
persons or severe injury will result. High pressure can cause dirt and other particles to become air-
borne and fly at high speeds. Eye protection, safety clothing and foot protection must be worn when
using this equipment. Spray gun kicks back — hold with both hands. Before disconnecting hose,
turn attached machine off and open spray gun to relieve pressure.
3
2
1

9.808-216.0 English Rev B (01/21) 8
1 Water filter
2 High-pressure pump
3 Unloader valve
4 Thermal relief valve
5. Heat exchanger
4.11 Flow paern

9.808-216.0 English Rev B (01/21) 9
5Overview of the appliance
5.1 Call outs 555 HE
8
5
12
9
10
346
7
11
12
8
12
11
14
13
15 16

9.808-216.0 English Rev B (01/21) 10
1Trigger gun
2Spray lance
3Motor switch
4Burner switch
5Hour meter
6Adjustable thermostat
7Spray nozzles
8Hose reel opon
9Power cord with GFCI
10 Flat free re
11 Pump
12 Unloader
13 Electric motor
14 Hose holder
15 Fuel cap with gauge
16 Fuel tank

9.808-216.0 English Rev B (01/21) 11
1 Outlet ports
2 Outlet / high pressure valve cover
3 Inlet ports
4 Inlet / low pressure valve cover
5 Manifold
6 Manifold bolt
5.2 Pump overview
2
11
3
4
3
5.2.1 Pump head overview
6
5
5.2.2 Pump cross-secon overview
1 Low pressure packing
2 High pressure packing retainer
3 Dipsck
4 Connecng rod
5 Bearing, Cranksha
6 Cranksha
7 Piston guide
8 Piston
9 Inlet port
1
2
34
5
6
8
9
7

9.808-216.0 English Rev B (01/21) 12
1 Manifold
7 Inlet check valves
9 Check valve cover
12 Piston
15 Outlet check valves
16 Manifold bolts
18 High pressure packing
22 Low pressure packing
37 Sight glass
45 Dipsck
5.2.3 Pump breakdown overview
9

9.808-216.0 English Rev B (01/21) 13
1 Knob, adjustment, by-pass pressure
2 Spring, pressure
3 Nut, lock
4 Piston, stem
5 Piston
6 By-pass port
7 Inlet port
8 Outlet port
5.3 Unloader / Bypass valve overview
5.4 Thermal relief valve overview
1 Inlet port
2 Thermal plate
3 Outlet direconal elbow
The thermal relief valve protects the pump from damaging
heat build-up while the unit is in bypass mode. Sensing a rise
in temperature, the valve opens and discharges a small
amount of heated uid. This allows cooler water to enter the
system and cool the pump. When the unit starts cleaning
mode, the cooler water entering the pump will cause the
valve to close immediately.
123
1
2
3
4
5
6
78

9.808-216.0 English Rev B (01/21) 14
5.5 Fuel pump
1 Inlet line from fuel tank
2 Fuel lter
3 Fuel pump
4 Fuel nozzle
5 Solenoid valve
6 Adjusng screw
7 Return line to fuel tank
5.6 High-eciency burner
1 Inlet from pump
2 Double-walled boiler cover
3 Outer heang coil
4 Inner heang coil
5 Exhaust gas ue
6 Fuel nozzle
7 Ignion electrodes
8 Air supply from blower
9 Outlet to trigger gun
10 Boiler base

9.808-216.0 English Rev B (01/21) 15
5.7 Fuel nozzle
1 Micro-lter
2 Thread
3 Angle of spray
In order to achieve opmum burner performance, the follow-
ing factors must be exactly matched to one another:
Fuel pressure
Vaporizaon of the fuel
Air Volume
Combuson chamber
Exhaust gas venng
5.8 Burner head assembly
1 Ignion electrodes
2 Burner cover
3 Fuel nozzle
4 Angle of spray
5 Securing screw
A-C Seng
5.9 Measure fuel consumpon (only for California)
This pressure washer hour meter is set from factory to register
the overall high pressure pump runme. For registering just
the runme of the fuel pump on the burner, in order to calcu-
late the fuel consumpon for SCAQMD Regulaons, the follow-
ing wiring modicaon is needed to be done.
WARNING. Always disconnect power before servicing.
1. Open control panel, refer to #1 and #2 of secon 6.5.18.
2. With the wiring diagram for California for the machine,
change jumper wire (A) connecon from the pump switch
(B) to the thermostat (C), using the piggyback terminal.
3. Close the control panel.

9.808-216.0 English Rev B (01/21) 16
6Service group
MAINTENANCE ITEM ACTION TIME FRAME REFERENCE SECTION
PUMP OIL
Inspect Oil level daily 6.4.1
Change
Aer rst 25 hours, then eve-
ry 300 hours or every 3
months 6.4.2
HIGH PRESSURE NOZZLE(S) Change 6 months Not shown
QUICK CONNECTS/O-RINGS Change Annually / As needed 6.4.3
HIGH PRESSURE HOSE Replace Annually (if there are any
signs of wear) Not shown
Drain water As needed 6.4.4
BURNER FUEL FILTER
Clean / replace As needed 6.4.4
HEATING COIL DESCALING Removed scale build up from
inside of coil piping As needed 6.4.5
HEATING COIL DESOOTING Remove soot build up from
outside of coil piping As needed 6.4.6
FUEL NOZZLE Replace Annually / As needed 6.4.7
FUEL TANK Clean Annually / As needed Not shown
FUEL LINES Replace Annually / As needed Not shown
6.1 Scheduled maintenance chart

9.808-216.0 English Rev B (01/21) 17
6.2 Trouble shoong chart
COMPONENT AREA PROBLEM TROUBLESHOOTING
REFERENCE SECTION
INADEQUATE CLEANING
POWER / LOW PRESSURE
ISSUES
Understanding the dierence between low, cavitaon and pulsang
pressure 6.3.1
Pulsang 6.3.2
Cavitaon 6.3.3
Low pressure 6.3.4
WATER LEAKING FROM
THERMAL RELIEF VALVE Water is leaking out of thermal relief valve 6.3.5
MACHINE IS VIBRATING The enre machine is vibrang 6.3.6
WATER LEAKIING FROM UN-
DER PUMP Water is leaking from under pump 6.3.7
OIL LEAKING FROM UNDER
PUMP Oil is leaking from under pump 6.3.8
PUMP OIL IS MILKY Pump oil is milky 6.3.9
UNLOADER CYCLES WHEN
TRIGGER IS RELEASED Pressure washer unloader is cycling 6.3.10
MACHINE WON’T TURN ON Electric motor will not turn on 6.3.11
MACHINE SHUTS OFF AFTER
RUNNING A WHILE Electric motor shuts o aer running a while 6.3.12
NO BURNER Burner will not turn on 6.3.13
BURNER TURNS ON BUT NO
FLAME Burner motor turns on but there is no ame 6.3.14
UNBURNED FUEL OUT OF
BURNER EXHAUST Raw fuel coming out of burner exhaust 6.3.15
BURNER FLAME TURN ON
BUT LOW WATER TEMPURA-
TURE
Burner motor and ame both work but the water output temperature
is low 6.3.16
WATER GETS TOO HOT Output water temperature is too hot 6.3.17
Troubleshoong is dened as a systemac ap-
proach to problem solving. Gathering infor-
maon on the problem issue and eliminang
what works in the system to narrow down to
what doesn’t work.

9.808-216.0 English Rev B (01/21) 18
Pulsaon is the feeling in your hand when holding the trigger
gun and/or wand that feels like a water pick. It is caused by an
interrupon in the high pressure stream. Figure 1 represents a
constant pressure washing stream.
Figure 2 represents a pulsaon in a pressure washer stream.
6.3 Trouble shoong process
6.3.1 Understanding the dierence between low, cavitaon and pulsang pressure
Cavitaon is the uctuaon of pressure up and down and is
caused by air being drawn into the sucon side of the pump.
The water gaps or air bubbles will “explode” when the water is
trying to be pressurized producing vibraon, noise and dam-
age to many components.
Figure 1 represents a constant pressure washing stream.
Figure 2 represents a cavitaon in a pressure washer stream
where the pressure uctuates up and down.
Most common causes of cavitaon are air being drawn into
the system from loose/broken inlet ngs, kinked or restrict-
ed inlet ow or heat.
Low pressure is the result of lower volume passing trough the
nozzle or the resistance of the nozzle being less then designed.
Figure 1 represents a correct pressure washing stream.
Figure 2 represents a low pressure stream.
6.3.2 Pulsaon
1. Inspect the inlet and outlet check valves for debris, func-
on and condion. See secon 6.5.1. If check valves are
good connue to #2.
2. Inspect packings, ceramic pistons and connecng rod con-
necon. See secon 6.5.2. If packings, pistons and con-
necng rod connects are good connue to #3.
3. Call Technical support for further instrucon.

9.808-216.0 English Rev B (01/21) 19
6.3.3 Cavitaon
1. Inspect the inlet screen for debris, funcon and condion.
See secon 6.5.3. If inlet screen is good, connue to #2.
2. Connect an adequate water supply to inlet of machine.
NOTE: an adequate water supply is 1 gallon a minute
more the specicaon of the machine no more than 8 bar
(116 PSI). Visually inspect the machine for ANY water drips
or leaks, including under pump. Drips or leaks from the
inlet plumbing can allow air to be introduced into the wa-
ter stream when pump is working. If there are no leaks,
connue to #3.
3. Remove thermal protector and plug plumbing where ther-
mal protecon was (only for tesng purposes). See secon
6.5.4. If thermal protector is good, connue to #4.
4. Inspect packings and ceramic pistons. See secon 6.5.2. If
packings and ceramic pistons are good, connue to #5.
5. Call Technical support for further instrucon.
6.3.4 Low pressure
CETA CPC100 standards for rang maximum working pressure
is to be measured at the pump head, upstream of regulator or
chemical injecon device, and can be rated 10% more than the
calculated average. Actual pressure can be as much as 10%
less than rated pressure. Our target of a max deviaon of 5%
was achieved on this machine.
1. Inspect the pressure nozzle. If the nozzle is in good, con-
nue to #2.
2. Test pressure reading at trigger gun hose quick discon-
nect. See secon 6.5.5. If pressure reading is low, connue
to #3.
3. Test pressure reading at outlet nipple on machine. See
secon 6.5.6. If pressure is good, inspect high pressure
hose and trigger gun for restricon issues or leaks. If pres-
sure tests low, connue to #4.
4. Make adaptor ng to test pressure reading at outlet of
coil. See secon 6.5.7. If pressure is good, inspect hose
from coil to outlet ng for restricon or leaks. If pres-
sure tests low connue to #5.
5. Make adaptor ng to test pressure reading at inlet of
coil. See secon 6.5.8. If pressure is good, inspect ngs
on outlet of coil for restricon or leaks. Also check coil for
scale build up See secon 6.4.5 or leaks. If pressure tests
low, connue to #6.
6. Test pressure reading at outlet of unloader. See secon
6.5.9. If pressure is good, inspect pressure hose to coil for
restricons or leaks. If pressure tests low, connue to #7.
7. Remove the unloader valve and test the pump for pres-
sure. NOTE: DO NOT STOP THE OUTLET WATER STREAM
See secon 6.5.10. If pressure tests low, connue to #4.
8. Inspect packings, ceramic pistons, and connecng rods.
See secon 6.5.2. If pieces are good, connue to #5.
9. Call Technical support for further instrucon.
6.3.5 Replacing leaking thermal relief valve
The thermal relief valve protects the pump from damaging
heat build-up while the unit is in bypass mode. Sensing a rise
in temperature, the valve opens and discharges a small
amount of heated uid. This allows cooler water to enter the
system and cool the pump. When the unit starts cleaning
mode, the cooler water entering the pump will cause the valve
to close immediately. If cold water is leaking out of the ther-
mal relief valve, then it probably has failed from being opened
too many mes.
1. Replace thermal relief valve. See secon 6.5.4. If the ther-
mal relief valve connues to leak, connue to #2.
2. Call Technical support for further instrucon.

9.808-216.0 English Rev B (01/21) 20
6.3.6 Vibraon
1. Inspect for cavitaon. See secon 6.3.3. If cavitaon is
not the issue, connue to #2.
2. Call Technical support for further instrucon.
6.3.7 Water leaking from under pump
1. Remove the pump manifold and inspect system. See sec-
on 6.5.2. If the pump parts are in good condion, conn-
ue to #2.
2. Call Technical support for further instrucon.
6.3.8 Oil is leaking from under pump
There are many seal points on the pump crankcase that help
keep oil in the pump. Inspect all sides of the pump to deter-
mine where the oil is coming from.
1. Check to see if the oil is leaking from the back of the pump
(the back of the pump is opposite of the manifold). If the
back of the pump is not leaking, connue to #2.
2. If the oil is leaking from the sha side of the pump, see
secon 6.5.13. If the oil is not leaking from the opposite
side of the pump from the engine, connue to #3.
3. If the oil is leaking from under the pump manifold side,
see secon 6.5.14. If the oil is not leaking from under the
manifold or connues to leak aer repairs, connue to #4.
4. Call Technical support for further instrucon.
6.3.9 Oil is milky
Milky oil, when the pump is not running, is an indicaon that
water may have been introduced to the oil.
1. Water can be introduced from cleaning the pump. The oil
dipsck is also a breather and can allow water to be intro-
duced to oil if a steam of water is used to clean the pump.
If this is the cause then change the pump oil. Run machine
to see if milky oil returns. If pump oil is again milky or wa-
ter has not been introduced to the oil from cleaning, con-
nue to #2.
2. Water can be introduced from condensaon. This can
occur if the machine has been sing a long me. If this is
the cause then change the pump oil. Test machine to see
if milky oil returns or water was not introduced to the oil
from condensaon. Connue to #3.
3. Water can be introduced to the oil via the pump manifold
side. Inspect the water moving side of the pump. See sec-
on 6.5.2. If the water moving side of the pump looks
good or oil connues to become milky, connue to #4.
4. Call Technical support for further instrucon.