23
Maintenance
Propane Gas
General Safety Precautions
Have a qualified gas service person assist in any gas
burner installation or service. Few maintenance people
or mechanics are knowledgeable in gas controls or
related safety practices. Propane gas is heavier than
air; unburned propane gas will gravitate to the floor
rather than rise out of the stack. Hence, adequate floor
space and good ventilation are especially important
with propane systems.
Gas Pressure Requirements
All propane fired machines operate on vapor propane
fuel only. They are designed to operate at a pressure of
11 w.c.i. (between 1/3 and 1/2 of one psi), and are often
operated at even higher pressures when extra heat is
needed.
Exterior regulators are needed to control the system.
Propane bottles are not included with the machine. A
high pressure regulator should be installed on the
propane bottle and a low pressure regulator attached to
the pressure washer.
Propane Cylinder Capacity
An important consideration with propane systems is the
capacity of the supply cylinder relative to the needs of
the burner. The burner operates on propane as a vapor
gas. As gas is used from the propane cylinder, the
liquid in the cylinder boils to maintain vapor gas
pressure. This boiling process cools the liquid, and in a
heavy, continuous-demand situation, the liquid
temperature can fall to the point at which it cannot
provide vapor gas as rapidly as is needed. In this case,
it may be necessary to warm the propane cylinder by
directing a warm spray, not over 120°F, on the cold
cylinder or by manifolding two propane bottles together
to increase total vaporization capacity. It is recom-
mended that a minimum 100 lb. vapor propane bottle
be used on the machine, depending on the length of
running time desired.
Burner Features
Operated Automatic Valve
This machine is equipped with an Intermittent Pilot
Ignition System. This system is designed to eliminate
the need for a constant burning pilot. Lighting of the
pilot is accomplished through electronic spark ignition
each time the burner and flow switch call for heat. The
pilot is not burning when there is no call for heat. Do not
attempt to light the appliance manually as a burn injury
or electrical shock may result. The pilot light will remain
on and the main gas valve is turned off when the spray
gun is closed.
Care of Main Burner
Due to condensation from heater coils dripping down
on the burners, scale build-up may occur in the burner
jet orifices.
1.
TO REMOVE BURNER MANIFOLD FROM
WATER HEATER COIL
Turn off the gas to the main burner by turning the
knob to the “OFF” position on the gas valve and
the main gas supply.
Disconnect the pilot and ignition lines from the
gas valve. Disconnect union in main burner line
below thermostat. Slide burner manifold out
through shell opening.
2.
TO CLEAN BURNER JETS
Select proper size drill for type gas involved. Use
pin vise to hold drill and ream out each jet orifice.
CAUTION: Do not ream out orifices to a
larger size.
If the water heater will be exposed to freezing weather,
an anti-freeze solution should be circulated through the
coil by whatever means are available for the particular
system the water heater is used on.
Landa VNG Operator’s Manual 8.913-939.0 - AB
