Preventative Maintenance; Maintenance And Service - Kärcher HDS 3.9/20 Ea Cage Operator's Manual

1. Use clean fuel — kerosene, No. 1 home heating
fuel or diesel fuel. Clean or replace fuel fi lter every
100 hours of operation. Avoid water contaminated
fuel as it will seize up the fuel pump. De-soot coils
month ly. Use an ad di tive if diesel is being used.
2. Check to see that the attached pressure washer
wa ter pump is prop er ly lu bri cat ed.
3. Follow winterizing instructions to prevent freeze
dam age to pump and coils.
4. Always neutralize and fl ush detergent from sys tem
af ter use.
5. If water is known to be high in mineral content, use
a water softener on your water system, or de-scale
as needed.
6. Do not allow acidic, caustic or abrasive fl uids to be
pumped through the system.
7. Always use high grade quality cleaning prod ucts.
8. Never run attached pressure washer pump dry for
ex tend ed pe ri ods of time.
9. If machine is operated with smoky or eye burning
ex haust, coils will soot up, preventing water from
reaching maximum operating temperature. (See
sec tion on Main te nance and Service).
1 0. Never allow water to be sprayed on or near the
mo tor or burner assembly or any electrical com-
po nent.
1 1. Delime coils as per instructions.
It is advisable, periodically, to visually inspect the
burn er. Check air inlet to make sure it is not clogged
or blocked. Wipe off any oil spills and keep equipment
clean and dry.
The areas around the pressure washer should be kept
clean and free of combustible materials, gasoline and
other fl am ma ble va pors and liquids.
The fl ow of ventilating air to the burner must not be
blocked or obstructed in any manner.

MAINTENANCE AND SERVICE

Unloader Valves:
Unloader valves trap pressure in the line when a shut-
off spray gun is closed. Machines with unloader valves
are preset and tested at the factory before shipping.
Tampering with the factory settings may cause per-
sonal injury and/or property damage and will void the
manufacturer's warranty.
Winterizing Procedure:
Damage due to freezing is not covered by warranty.
Ad here to the following cold weather procedures when-
ev er the washer must be stored or operated outdoors
under freezing conditions.
During winter months, when temperatures drop be low
32°F, pro tect ing your machine against freezing is nec-
16

PREVENTATIVE MAINTENANCE

HDS 505, 508, 509, 510 • 9.800-078.0 - N
es sary. Store the ma chine in a heated room. If this is
not pos si ble then mix a 50/50 solution of anti-freeze/
water or wind shield wash er fl uid with water in a 5 gal-
lon buck et. Place a short section of garden hose into
the bucket and connect it to the machine. Elevate the
bucket and turn the pump on to si phon the anti-freeze
through the ma chine. If com pressed air is available, an
air fi tting can be screwed into the inlet connector and
by injecting com pressed air, all water will be blown out
of the system.
If you have an optional fl oat tank, pour the antifreeze
into this tank and run machine until antifreeze exits
dis charge nipple.
High Limit Hot Water Thermostat:
For safety, each machine is equipped with a high lim it
con trol switch. In the event the temperature of the wa ter
should exceed its operating temperature, the high limit
control will turn the burner off until the water cools.
Pumps:
Use only SAE 30 weight non-detergent oil. Change oil
af ter fi rst 50 hours of use. Thereafter, change oil every
three months or at 500 hour intervals. Oil level should
be checked by using the dipstick found on the top of
the pump or by the red dot visible through the oil gauge
win dow. Oil should be maintained at that level.
Cleaning of Coils:
In alkaline water areas, lime deposits can ac cu mu late
rap id ly inside the coil pipes. This growth is in creased
by the extreme heat build up in the coil. The best
pre ven tion for lim ing conditions is to use high quality
clean ing de ter gents. In areas where alkaline water is an
ex treme prob lem, pe ri od ic use of deliming powder will
remove lime and other deposits before coil becomes
plugged.
Deliming Coils With A Pressure Washer:
Periodic fl ushing of coils is rec om mend ed.
Step 1 Fill a 5 gallon bucket with 4 gallons of water,
then add 1 lb. of deliming powder. Mix thor-
ough ly.
Step 2 Remove the high pressure nozzle from the
pres sure wand and put the wand into the
buck et. Se cure the trig ger on the spray gun
into the open position.
Step 3 Attach a short section (3-5 ft.) of garden hose
to the attached pressure washer to siphon so-
lu tion from the el e vat ed bucket. Start up pres-
sure wash er, al low ing so lu tion to be pumped
through pressure wash er and into HPB coils
and back into the buck et. So lu tion should be
al lowed to cir cu late 2-4 hours.