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F. TEST HIGH LIMIT CONTROL
AND ADJUST
While
burner
is operating,
move
indicator
on high limit control
below
actual
boiler
water
temperature.
Burner
should
go off while
circulator
continues
to operate.
Raise
limit setting
above
boiler
water
temperature
and burner
should
reignite
after
pre purge
and igniter
warm-up
period.
Set the high limit control
to the design
temperature
requirements
of the system.
Maximum
high
limit setting
is 200°F.
Minimmn
high limit setting
is 100°F.
G. TEST OTHER
SAFETY
CONTROLS
If the boiler is equipped with a low water cut off, a manual reset high limit, or additional safety
controls, test for operation as outlined by the control manufacturer.
Burner should be operating
and should go off when controls are tested. When safety controls are restored, burner should
reignite.
H. SET THERMOSTAT
HEAT ANTICIPATOR
(IF USED) AND VERIFY
THERMOSTAT
OPERATION
For a single thermostat
connected
to the yellow thermostat
lead wires in the furnished
field wiring
junction
box, the heat anticipator
should be set at 0.7 amps.
For other wiring configurations,
refer
to the instructions
provided by the thermostat
manufacturer
regarding
adjustment
of heat
anticipator.
Cycle boiler with thermostat.
Raise the thermostat
to the highest setting and verify
boiler goes through
normal start up cycle.
Lower thermostat
to lowest setting and verify boiler
goes off.
I.
MEASURE
THE NATURAL
GAS INPUTRATE
Correct
input rate is essential
for proper and efficient operation
of the burner and boiler.
I.
Determine
elevation
at installation
site.
2.
See page 4 and 5 of this manual to determine
the correct input rate for the local elevation.
3.
Obtain the yearly average heating value of the local gas supply from the gas utility.
At sea
level elevation,
it should be approximately
I000 Btu's per standard cubic foot.
4.
Operate boiler for 5 minutes.
5.
Turn off all other gas appliances,
extinguishing
standing pilots where applicable.
6.
At gas meter, measure
time in seconds required
to use one cubic foot of gas.
7.
Calculate
input rate according
to the following formul
3600 x heating
value
from step 3
Btuh input rate =
time from
step6
.
Measured
input rate should be within +/-2%
of the input rating from step 2. If within 2%,
go to step 9. If not, adjustment
is required,
proceed as follows:
a.
Turn boiler off.
b.
Set up U-tube manometer
or differential
pressure
gauge for measuring
manifold
pressure,
see FIG.17.
c.
Manometer
or gauge must be able to read at least 0.0 to 3.0 inches water column of
pressure,
and resolve to at least 0.1 inches water column.
d.
Turn boiler on.
e.
Manifold
pressure
has been nominally
set at 2.5 inches w.c.
Manifold pressure
and input
rate must always be measured
with pressure
regulator
cover screw installed.
Cover screw
must be removed
for adjustment.
Manifold
pressure
reading will change (increase)
when
cover screw is removed.
39
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