ICP NOLF105A12D, Installation Instructions Manual

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2.3.3 Combustion chamber curing
Some moisture and binders remain in the ceramic combustion
chambers after fabrication. It is important to clear the chamber
of this residue before testing. If you smoke test before curing,
the instrument may become damaged. To cure the chamber,
run the unit for 3 consecutive cycles, with 3 minutes of
elapsed time in between each cycle. The burner must operate
for about 3 minutes per cycle. The exhaust will have a
pungent odour and produce a white cloud of steam.
2.3.4 Smoke / CO
2
test
1. On chimney installations, pierce a test hole in the smoke
pipe 18’’ above the furnace breech. On side-wall vented
installations, remove the threaded cap from the extended
test pipe that is welded into the 4-bolt breech plate. Insert
the smoke test instrument probe into the open hole;
2. From a cold start, let the unit operate during 5 to 10
minutes;
3. Set the burner air setting until just a trace of smoke
results (#1 on the Bacharach scale);
4. Take a CO
2
sample at the same test location where the
#1 smoke reading was taken and make note of it.
Example: 13.8% of CO
2
or 2.5% of O
2
;
5. Adjust the burner air setting to obtain a CO2 reading
1.5% lower (or a O2 reading 2.0% higher) than the
reading associated with the #1 smoke. Example: 12.3%
or CO2 or 4.5% of O2;
6. This method of adjusting the burner will result in clean
combustion and ensure the proper functioning of the
system.
2.3.5 Perform the supply air temperature rise test
1. Operate the burner for at least 10 minutes;
2. Measure the temperature of the air in the return air
plenum;
3. Measure the temperature of the air in the largest trunk
coming off the supply air plenum, just outside the range of
radiant heat coming off the heat exchanger; 30 cm (12")
away from the plenum on the main take-off is usually
sufficient;
4. The temperature rise is calculated by subtracting the
return air temperature from the supply air temperature;
5. If the temperature rise exceeds the temperature specified
in Tables 4.1 to 4.3, change to the next higher blower
speed tap until the temperature rise falls to this
temperature or below. If the excessive temperature rise
cannot be reduced by increasing fan speed, investigate
for ductwork restriction(s), dirty or improper air filter,
overfiring caused by excessive pump pressure, or
improper nozzle sizing.
2.3.6 Vent temperature test
1. After 5 to 10 minutes of operation, place a thermometer in
the test hole located in the breech pipe;
2. The vent temperature should be between 204 and
302°C (400 and 575°F). If not, check for improper air
temperature rise, pump pressure, nozzle size, or for a
badly sooted heat exchanger.
2.3.7 Overfire pressure test procedure
The overfire draft that is taken through the observation port,
located above the burner, is a measurement necessary to
determine if there is a blockage in the heat exchanger or the
flue pipe. Refer to the Technical Specifications in this
manual for overfire pressure values. A high pressure
condition may be caused by excessive combustion air, due
to the air band being too wide open, or a lack of flue draft
(chimney effect) or some other blockage, such as soot in the
secondary section of the heat exchanger or the use of an
oversize nozzle input or high pressure pump.
2.3.8 Fan-Limit adjustment
Modification of the “FAN ON” and “HI” limit settings on the
Fan-Limit can cause a malfunctioning of the furnace and result
in premature wear of the heat exchanger.
Please refer to the different adjustment values in Figure 4.
CAUTION
Modification of the factory set limits will void the
warranty.
2.3.9 Limit control check
After operating the furnace for at least 15 minutes, restrict the
return air supply by blocking the filters or the return air register
and allow the furnace to shut off on High Limit. The burner will
shut off but the blower will continue to run.
Remove the obstruction and the burner should restart after a
few minutes.
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