Williams 5001922 Owner's Manual page 9

Start-Up Procedure
WARNING
DANGER OF PROPERTY DAMAGE,
BODILY INJURY OR DEATH.
LIQUEFIED PETROLEUM L.P. GAS IS HEAVIER
THAN AIR AND IT WILL SEI-rLE IN ANY LOW
AREA, INCLUDING OPEN DEPRESSIONS AND IT
WILL REMAIN THERE UNLESS AREA IS
VENTILATED.
NEVER ATTEMPT STARTUP OF UNIT BEFORE
THOROUGHLY VENTILATING AREA.
Check the heater operation as outlined in the following in-
structions. If any sparking, odors or unusual noises are
encountered, shut off electric power immediately. Recheck
for wiring errors, or obstructions in or near fan motor (if
equipped).
CHECK GASINPUT AND PRESSURES
For heater located at elevations between sea level and
2000 feet, the measured input must not be greater than
the input shown on the rating plate of the furnace. For
elevations above 2000 feet, the measured input must not
exceed the input of the rating plate reduced by 4 percent
for each 1000 feet that the heater is above sea level.
Gas supply pressure and manifold pressure with the
burner operating must also be as specified on the rating
plate.
lype of Gas Manifold Pressure, In. W.C.
Natural 4
L.R 10.5
Rated input will be obtained on 2500 Btu propane at 10.5
inch manifold pressure and factory-sized orifices. If LP gas
having a different heating value is supplied, orifices must
be changed by a qualified service technician before the
heater is operated.
CHECK THE MANIFOLD GAS PRESSURE
A tapped opening is provided in the gas valve to facilitate
measuring the manifold gas pressure. A "U Tube"
manometer having a scale range from 0 to 12 inches of
water should be used for this measurement. The manifold
pressure must be measured with the burner and pilot
operating. Any major changes in the flow must be made
by changing the size of the bumer orifice. Check with your
WILLIAMS service department for proper orifice sizing.
CHECK THERMOSTAT
Check thermostat operation. When set above temperature
shown on the thermostat, the main burner should light.
Make certain the thermostat turns off the heater when
room temperature reaches the selected setting and starts
the heater when room temperature falls a few degrees.
CHECK THE GAS INPUT (NATURAL GAS ONLY)
WARNING
NATURAL GAB HEATING VALUE (BTU PER CUBIC
FOOT) CAN VARY SIGNIFICANTLY, THEREFORE,
IT IS THE INSTALLER'S RESPONSIBILITY TO BEE
THAT BTU INPUT TO THE FURNACE IS ADJUSTED
PROPERLY. FAILURE TO DO SO COULD CAUSE
HEAT EXCHANGER FAILURE, ASPHYXIATION, FIRE
OR EXPLOSION, RESULTING IN DAMAGE, BODILY
INJURY OR DEATH. REFER TO THE NATURAL
FUEL GAS CODE (NFPA-54) TO BE SURE THE FUR-
NACE IS BURNING FUEL AT THE PROPER RATE.
Underfiring could cause inadequate heat, excessive con-
densation or ignition problems. Overfiring could cause
sooting flame impingement or overheating of heat ex-
changer.
Before starting natural gas input check, obtain heating
value of gas (BTU per cubic foot) at standard conditions
from your local supplier. This factor is used in "Check the
Gas Input" section and procedure.
To measure the input using the gas meter, proceed as
follows:
Step 1: Turn off gas supply to all other appliances except
the furnace.
Step 2: With the heater operating, time the smallest dial
on the meter for one complete revolution. If this
is a 2 cubic foot dial, divide the seconds by 2; if
it is a 1 cubic foot dial, use the time in seconds
as is. (3,600 = Sec. Per Hr.) This gives the
seconds per cubic foot of gas being delivered to
the heater.
Step 3: Assuming natural gas with a heating value of
1000 Btu per cubic foot and 34 seconds per cubic
foot as determined by step (2), then:
Input: 1,000 X 3,600 + 34 = 106000 Btu Per Hour
Step 4:
This measured input must not be greater than the
input indicated on the rating plate of the heater.
Relight all other appliances turned off in step 1
above. Be sure all pilot burners are operating.
CHECK PILOTBURNER
The pilot flame must envelop 1/2 to 5/8 inch of thermocou-
pie or generator. See Fig. 5. Pilot flame is preset at the
factory, so ordinarily does not require field adjustment. If
adjustment is needed, see page 14.
J__
1/2 TO5/s
,_-- RLOT
FRONT
_EW
--9---
Fig. 5