Service manual

39
12 OPERATION AND
SERVICE
12.1 PRE-START CHECKLIST
Before operating the boiler, the entire system
must be filled with water, purged of air and
checked for leaks. Do not use Stop leak or other
boiler compounds. The gas piping must also be
leak tested.
Any safety devices including low water cutoff,
flow switch and high limit used in with this boiler
must receive periodic inspection (every six
months) to assure proper operation. A low water
cutoff of the float type should be flushed every
six months. All relief valves should be inspected
and manually operated every six months.
For your safety follow the lighting and operating
instructions below and on the boiler.
To turn on main burner, slowly open firing valve
after pilot is established.
Set primary system controller to desired
temperature.
To turn off boiler close main manual gas valve,
close pilot manual valve and turn off electric
power to system.
12.2 START-UP
Gas appliances are rated based on sea level
operation with no adjustment required at
elevations up to 2000 ft. At elevations above
2000 ft the input rating must be reduced by 4%
for each additional 1000 ft elevation. Never
increase the input of the appliance above that
for which it is rated.
Pilot Pressure Setting
The pilot was preset at the factory. The following
description is for the benefit of the start-up
technician should minor adjustment be required.
The pilot burner is controlled by a separate pilot
valve. Pilot pressure setting is as shown in Table
15. A view port is provided on the appliance’s
return end to view the pilot and the main
burners. If adjustment is necessary the following
steps must be followed: Remove the lower front
jacket panel; Remove the ⅛” plug from the
elbow pressure tap and connect a manometer;
Remove regulator adjustment screw cap from
the pilot valve; Rotate the regulator adjustment
screw clockwise to increase the manifold
pressure or counterclockwise to decrease it;
Once satisfied replace the regulator adjustment
screw cap and the elbow pressure tap plug.
Table 15 – Gas pressures at inlet to pilot
PROPANE
NATURAL
GAS
Minimum (inches W.C.) 3.9 1.3
Maximum (inches W.C.) 9.3 3.5
Figure 27: MicoFlame Grande 2010 – 4000
Gas Valve
To adjust the high fire setting
Set the Target Temperature to 190
o
F using the
BTC 1 Controller.
Locate screw (1) labeled as <<P
GAS
/P
AIR
>> and
make adjustments as necessary to satisfy the
combustion values in Table 14. The markings on
the setting screws are labeled as “+” and “-“, for
more and less gas, respectively. Turn the screw
1/4 turn in either way for each adjustment to
keep track of the adjustments. After adjusting
the screw wait a moment for the combustion
levels to stabilize before attempting to make any
further adjustments. Continue this procedure
until combustion levels are satisfied.
Reset the Target Temperature to normal
operating conditions on the BTC 1 Controller.
To adjust the low fire setting
Observe the Boiler Inlet Temperature. Set the
Boiler Target temperature so that it is 10
o
F
above the Boiler Inlet Temperature. The boiler
will begin to modulate to low-fire as setpoint is
being reached. The actual modulation rate can
be shown on the screen as Modulation, this will
be shown as a percentage.