UTICA BOILERS UB90 125 Installation Manual And Operating Instructions page 25

It is important that this appliance operate between 8.5 and 10% CO
that the appliance is operating in this range, follow the steps below.
1. Check incoming gas pressure to the appliance using a pressure gauge with
a resolution of 0.1" w.c. or better and a range from 0" to at least 14" w.c. Close
the gas shut-off inside the boiler jacket. Locate the inlet pressure tap on the
gas valve (see Figure 15 in Section XI). Open the inlet pressure tap screw ½
turn and connect the positive side of the pressure gauge to the inlet pressure
tap. Open the gas shut-off. The gas pressure should read between 4" and 10"
w.c. for natural gas and between 10" and 14" w.c. for propane gas.
2. Drill a hole in the plastic CPVC vent pipe or exhaust tee, just large enough
to allow access for the sample probe of your combustion analyzer.
3. Turn the thermostat to the closed position so the appliance is activated.
4. Allow the appliance to run for approximately 5 minutes.
5. Insert the sample probe of your combustion analyzer into the hole you
drilled in step 2 above, about halfway into the exhaust gas stream. Take a
flue gas reading and observe the CO
the CO
2
clockwise increases the rate and the CO
clockwise decreases the rate and the CO
bilize for approximately 1 minute after adjusting the throttle screw before you
take a reading with your combustion analyzer.
6. After adjustments are made stop the appliance, disconnect the pressure
gauge, tighten the inlet pressure tap on the gas valve, remove the CO
from the CPVC pipe, and seal the hole with an appropriate material.
7. Return the thermostat switch to its original position.
After any adjustment to the appliance, observe several complete cycles to ensure
that all components function correctly.
SET THERMOSTAT
TO DESIRED TEMPERATURE
Set thermostat to desired room temperature and
observe several complete cycles to verify proper
operation.
ADJUSTMENTS AND CHECKOUT
value is between 8.5 and 10%. Turning the throttle screw counter-
FINAL CHECKOUT OF THE INSTALLATION
value. Adjust the throttle screw until
2
value. Turning the throttle screw
2
value. Allow the appliance to sta-
2
FINAL REVIEW AND SIGNOFF
Review all instructions shipped with this boiler with
owner or maintenance person. Instructions must be
affixed on or adjacent to the boiler. Then complete
and sign the "Installation and Checkout Certificate"
at the end of this manual.
25
. To verify
2
meter
2