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Cast Iron Condensing Boilers – Installation Manual
FlexCore Stainless Steel Condensing Boilers – Installation Manual
To adjust the pilot the following steps must be
taken:
1. Remove the pilot gas pressure regulator cap.
2. Turn the pressure regulator adjustment screw clock-
wise to increase the pressure and counterclockwise
to decrease it.
3. Replace the pressure regulator adjustment screw
cap.
Never force the regulator adjustment screw
beyond the stop limits or damage to the
regulator will occur!
Pilot flame UV signal
Before you check the pilot signal you need to make sure
the polarity of the 120v supply to the ignition transformer
is correct. To do this close the manual main shut-off
valve 2 (Figure 17) and the manual pilot shut-off valve.
With the unit powered generate a call for heat. The boiler
will start to go through it start up sequence. During the
ignition/pilot sequence observe the lights on the
Honeywell 7895C. The pilot light should come on but not
the flame light. If the flame light comes on along with
the pilot light, interrupt the call for heat and turn off the
main power. Reverse the 120v supply leads to the
Honeywell 652B ignition transformer and run this test
again. With this done the flame signal should be
between 3vdc and 5vdc. Check the voltage on the test
connections of the Honeywell 7895C's amplifier with a
dc voltmeter.
Figure 20 - Pilot Assembly
CHECKING, ADJUSTMENT & OPERATION
Spark Gap
The gap has to be measured and adjusted with the
igniter removed from the boiler. Observe the trial for
ignition to confirm that the spark is strong and
continuous. If not, allow the electrodes to cool. Check
and adjust the spark gap as shown in Figure 19.
Electrode tips should face slightly downward.
Figure 19 - Spark Gap
Pilot Adjustment
Connect one side of a manometer or pressure gauge
having a minimum range of 6 in., 15 mm WC to the
manometer pressure tap (pilot gas barbed connection)
on the pressure test manifold located inside the upper
control panel. (See Figure 21). For units (CK3500 -
CK9000), add additional manometers to the (pilot gas
barbed connection) provided for the middle and rear
modules. Leave the other side of the manometer open
to atmosphere. Open the pilot gas shut-off valve. With
the unit powered generate a call for heat. When the
prepurge is complete the ignition/pilot trial will begin. At
this point put the Honeywell 7895C test switch in the test
position. For units (CK3500 - CK9000), place the test/
run switch on both flame safeguards into test mode. The
control will hold in the ignition/pilot sequence allowing
you to check the pressure. Verify that the pilot gas
pressure is within a range of (2.5 in.-3.5 in. WC). Check
the pilot air pressure using the service valve marked
"Pilot Air Valve". The pilot air pressure should be .60 in.
WC (± 0.1 in.).
A
RIOM-0222_B
DETAIL A
SCALE 1 : 1
BEVEL UP
BEVEL DOWN
