96-610 • LANDA VNG/VLP • REV. 9/05
OPERA
T
OR’S MANU
AL
PRESSURE W
ASHER
16
MAINTENANCE & SERVICE
HEATING COIL
Condensation from Heating Coil
When cold water is being pumped into the water heater
coil, and the burner is on, condensation will form on
the coil and drip down into the burner compartment,
giving the appearance of a leaking coil, particularly on
cold humid days.
To Check Water Heater Coil for Leaks:
With the main burner “OFF” start machine and allow it
to run a few minutes. Look into the burner compart-
ment with a drop light or flashlight. If no leaks are vis-
ible, then water dripping from coil is from condensa-
tion.
Deliming Coil:
In alkaline water areas, lime deposits can accumulate
rapidly inside the coil pipes. This growth is increased
by the extreme heat build up in the coil. The best pre-
ventative for liming conditions is to use high quality
cleaning detergents. In areas where alkaline water is
an extreme problem, periodic use of Landa Deliming
Powder will remove lime and other deposits before coil
becomes plugged. (See Deliming Instructions for use
of Landa Deliming Powder.)
Periodic coil deliming is recommended.
1. Fill a container with 4 gallons of water, then add 1
lb. of deliming powder. Mix thoroughly.
2. Remove nozzle from spray gun assembly and put
spray gun into container.
3. Attach a short section (3-5 ft.) of garden hose to
machine to siphon solution from an elevated con-
tainer or add mixture to the float tank. Turn pump
switch on allowing solution to be pumped through
coil and back into the container. Solution should
be allowed to circulate 2-4 hours.
4. After circulating solution flush entire system with
fresh water. Reinstall nozzle in spray gun.
GAS VALVE REGULATOR
ADJUSTMENT
Adjustment of the built-in regulator isn’t normally nec-
essary, since it is preset at the factory. However, field
adjustment may be accomplished as follows:
1. Attach manometer at pressure tap port.
2. Remove regulator adjustment screw cap.
3. With a small screwdriver, rotate the adjustment
screw clockwise to increase or counterclockwise
to decrease gas pressure.
4. Replace regulator adjustment screw cap (see Fig-
ure 5 below).
Figure 5
Pressure Relief Valve
Each machine is equipped with a relief valve to relieve
pressure in the system when higher than normal oper-
ating pressures are encountered. If operating pressure
of machine is found to be normal and relief valve con-
tinues to leak, repair or replace the valve. CAUTION:
Relief valve can become obstructed by deposits and
must be unscrewed at least once per year to allow dis-
charge.
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 re-
lated 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 pro-
pane systems.
Gas Pressure Requirements
All propane fired machines operate on vapor propane
fuel only. They are designed to operate at a pressure
o
f
11 w.c.i. (between 1/3 and 1/2 of one psi), and are of-
ten operated at even higher pressures when extra heat
is needed.
Gas Valve Regulator Adjustment
On/Off
Switch
Outlet View
Inlet
Manifold Pressure
Adjustment Screw
Under Cap
Gas Valve
Regulator
Adjustment
Lines To
Pilot Light
Summary of Contents for VNG4-2000
Page 2: ......
Page 54: ......
Page 56: ...Form 96 610 Revised 9 05 Printed in U S A WATER CLEANING SYSTEMS...