Landa PDHW5-35624E, Operator'S Manual

15

Maintenance

Winterizing Procedure:

Damage due to freezing is not covered by warranty. 
Adhere to the following cold weather procedures 
whenever the washer must be stored or operated 
outdoors under freezing conditions.

During winter months, when temperatures drop below 
32°F, protecting your machine against freezing is 
necessary. Store the machine in a heated room. If this 
is not possible then mix a 50/50 solution of anti-freeze 
and water in the float tank. Turn the engine on to siphon 
the anti-freeze mixture through the machine. If 
compressed air is available, an air fitting can be 
screwed into the float tank by removing the float tank 
strainer and fitting. Then inject the compressed air. 
Water will be blown out of the machine when the trigger 
on the spray gun is opened.

High Limit Hot Water Thermostat:

For safety, each machine is equipped with a tempera-
ture sensitive high limit control switch. In the event that 
the water should exceed its operating temperature, the 
high limit control will turn the burner off until the water 
cools then automatically reset itself. The thermostat 
sensor is located on the discharge side of the heating 
coil. The thermostat control dial is located on the 
control panel.

Pumps:

Use only SAE 10W-40 weight non-foaming oil. Change 
oil after first 50 hours of use. Thereafter, change oil 
every year or at 500 hour intervals. Oil level should be 
checked through use of dipstick found on top of pump, 
or the red dot visible through the oil gauge window. Oil 
should be maintained at that level.

Cleaning of Coils:

In alkaline water areas, lime deposits can accumulate 
rapidly inside the heating coil. This growth is increased 
by the extreme heat build up in the coil. The best 
preventative for liming conditions is to use high quality 
cleaning detergents. In areas where alkaline water is 
an extreme problem, periodic use of Landa Descaling 
Powder (Part #8.914-296.0) will remove lime and other 
deposits before coil becomes plugged. 

Periodic descaling of the heating coil is recom-
mended so please consult your local Landa Dealer 
for instructions.

Removal of Soot and Heating Coil:

In the heating process, fuel residue in the form of soot 
deposits may develop between the heating coil pipe 
and block air flow which will affect burner combustion. 
When soot has been detected on visual observation, 
the soot on the coil must be washed off after following 
the coil removal steps (See Coil Removal page).

Rupture Disk:

If pressure from pump or thermal expansion should 
exceed safe limits, the rupture disk will burst allowing 
high pressure to be discharged through hose to ground. 
When the disk ruptures it will need to be replaced. 
Torque new rupture disk to 35 ft. lbs.

Fuel:

CAUTION: Use Ultra Low Sulfur Fuel only.

Diesel fuel must be clean, fresh, meet fuel specifica-
tions and be sourced from a known and reputable 
supplier. Clean, fresh and properly specified diesel fuel 
will provide assurances of maximum engine perfor-
mance and maximum fuel injection system longevity. 
The use of out-of-spec, dirty or questionable quality 
diesel fuel will result in engine performance and start 
ability problems as well as reductions in engine and fuel 
injection system life.

Use clean fuel oil that is not contaminated with water 
and debris. Replace fuel filter and drain tank every 100 
hours of operation.

Fuel Control System:

This machine utilizes a fuel solenoid valve located on 
the fuel pump to control the flow of fuel to the combus-
tion chamber. The solenoid, which is normally closed, is 
activated by a flow switch when water flows through it. 
When the operator releases the trigger on the spray 
gun, the flow of water through the flow switch stops, 
turning off the electrical current to the fuel solenoid.

The solenoid then closes, shutting off the supply of fuel 
to the combustion chamber. Controlling the flow of fuel 
in this way gives an instantaneous burn-or-no-burn situ-
ation, thereby eliminating high and low water tempera-
tures and the combustion smoke normally associated 
with machines incorporating a spray gun. Periodic 
inspection, to insure that the fuel solenoid valve 
functions properly, is recommended. This can be done 
by operating the machine and checking to see that the 
burner is not firing when the spray gun is in the OFF 
position.

Landa PDHW Series Operator’s Manual  8.919-980.0 - B