L.B. White 350 Premier - Manual (Page 21)

OUTLET
GAUGE
INLET
GAUGE
GAS CONTROL
LOW HEAT
HIGH HEAT
OFF
ON
LO HI
0
5
10
15 20 25
30
35
0
5
10
15 20 25
30
35
ATTENTION
■ The gas control valve in this heater is a two stage
control. This will allow the heater to operate at a
decreased heat output when heating requirements are
less than severe. The decreased output is
approximately one half the rated output of the heater.
■ The following explains a typical procedure to be followed
in checking gas pressures.
■ The gas pressures will vary depending upon fuel type.
■ Consult the dataplate on the heater or page 4 in this
manual for specific pressures to be used in conjunction
with this procedure.
■ Gas pressure measured at the inlet to the gas valve is
Inlet Pressure and gas pressure measured at the outlet
of the gas valve is Burner Manifold Pressure.
MATERIALS REQUIRED
Quantity Description
2 Gas pressure gauges capable of reading
up to 35 in. W.C. (may also be ordered
from L.B. White, part # 00764)
A. PPreparation
1. Disconnect the heater from the electrical supply and
close the fuel supply valve to the heater.
2. Open the case access panel at burner end of heater.
3. Brush or blow off any dust or dirt in the vicinity of the
gas control valve.Open the fuel supply valves to the
heater and reconnect the heater electrical supply.
B. G Gauge IInstallation
1. Locate the gas control pressure taps. See Fig. 29.
Remove the pressure tap plugs using a 3/16 in. allen
key.
2. Securely connect pressure gauges at these points.
3. Open the fuel supply valves to the heater and
reconnect the heater electrical supply.
4. Start the heater
C. R Reading PPressures
1. With the heater operating, the pressure gauges
should read the pressures specified on the dataplate.
2. Do the readings at the inlet and outlet pressure
gauges agree with that specified on the dataplate?
If so, then no further checking or adjustment is
required. Proceed to section D.
3. If the inlet pressures do not agree with that specified
on the dataplate, then the regulator controlling gas
pressure to the heater requires adjustment.
4. If the inlet pressure is correct but the burner manifold
pressure does not agree with that specified on the
dataplate, then the high and low heat output feature
of the gas control valve requires adjustment.
5. Turn the thermostat down to its lowest setting.
Remove the cap from the high and low heat adjusting
screws at the two stage pressure regulator on the gas
control valve.
6. Slowly turn up the thermostat until a pressure is read
no greater than 2 in. W.C. (LP) or .8 in.W.C. (N.G.) at
the outlet pressure gauge. If less than 2 in. W.C.
(L.P.) or .8 in. W.C.. (N.G.) is read, the low heat setting
at the regulator on the gas control will require
adjusting. Turn clockwise to increase, or
counterclockwise to decrease.
7. Turn the thermostat completely up. You should see
the gas pressure increase from 2 in. W.C. (L.P.) or .8
in.W.C. (N.G.) at low heat to 8.0 in.W.C.(L.P.) or 3.5 in.
W.C. (N.G.) high heat. If less or greater than 8.0 in.
W.C. (LP) or 3.5 in. W.C. (N.G.), the high heat setting
must be adjusted clockwise or counterclockwise
accordingly until proper pressure is achieved.
D. C Completion
1. Once the proper inlet and burner manifold pressures
have been confirmed and/or properly set, close the
fuel supply valve to the heater and allow the heater to
burn off any gas remaining in the gas supply line.
2. Disconnect the heater from its electrical supply and
close fuel supply valve.
3. Remove the gauges.
4. Install pressure tap plugs.
5. Open fuel supply valve and reconnect electrical
supply to heater. Start the heater and check for gas
leaks.
7. Set thermostat to desired temperature.
FIG. 29
WARNING
■ Do not disassemble the gas control valve.
■ Do not attempt to replace any components of the gas
control valve.
■ The gas control valve must be replaced if any physical
damage occurs to the control valve assembly.
■ Failure to follow this warning will result in fire or
explosions, leading to injury or death to humans, and
property damage.
20
OUTLET TAP
INLET TAP
Gas Pressure Checks