Combustion Check; Limit Control Check; Year Round Air Conditioning; Table 4 - CAC / BDP CBMAAA Installation Instructions Manual

3.4 COMBUSTION CHECK
IMPORTANT: The heat exchanger metal surfaces may
have oil and the baffle insulation also contains binders.
These products will burn or evaporate when the unit
operates for the first time. Because of this, the smoke
reading may be inexact during the first minutes of operation.
Therefore, the unit must operate during at least 60 minutes
before taking any readings to adjust the combustion quality.
Let the unit cool down before making any adjustments.
IMPORTANT: The combustion check verification MUST be I
performed after the nozzle replacement or the burner I
cleaning. After these manipulations, the combustion I
parameters are necessarily modified. Refer also to the I
burner instruction manual. I
In order to obtain optimum performance from the oil burner,
the following set-up procedures must be followed by
referring to the Technical Specifications, Table 5 in this
manual:
1. A test kit to measure the smoke, flue draft and over-fire
pressure should be used in order to obtain the proper
air band setting. Although all of the above
measurements are required for optimum set up and
efficiency, the most important reading that must be
taken is the smoke number in the flue pipe, downstream
from the regulator;
2. The proper smoke number, as established by way of
engineering tests, is between 0 and 1. This degree of
smoke emission is commonly referred to as a "trace". It
is recommended that a Bacharach True Spot Smoke
Test kit or equivalent be used;
3. Follow the next steps to do the combustion check
verification:
a. Drill a minimum proper diameter (about 9/32") test
hole in the flue pipe, approximately 18 inches from
the furnace breech;
b. From a cold start, let the unit operate for about 5
minutes;
c. Set the burner air setting until you have between 0
and 1 on the Bacharach Scale (or a "trace");
d. Take a CO2 sample at the same test location where
the smoke reading was taken and make note of it;
e. Adjust the burner air setting to obtain a CO2 reading
1.5% lower (or a 02 reading 2.0% higher) than the
reading associated with the "trace" of smoke;
f. This method of adjusting the burner will result in
clean combustion (Bacharach smoke scale
between 0 and a trace) and ensure the proper
functioning of the system.
4. A barometric draft regulator, supplied with the furnace,
must be installed, in order to ensure proper draft
through the furnace. The barometric damper must be
mounted with the hinge pins in a horizontal position and
the face of the damper vertical for proper functioning,
(see instructions included with damper). After the
furnace has been firing for at least five minutes, the
draft regulator should be set to between -0.025" W.C.
and -0.035" W.C.;
5. The over fire pressure that is taken through the
observation door located in the centre of the front panel
above the burner is a measurement that is necessary to
determine if there is a blockage in the heat exchanger
or the flue pipe. Please refer to the Technical
Specifications in this manual for over fire pressure
12
6.
3.5
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;
After all the set up procedures mentioned above have
been completed, the burner should be fired and an
inspection mirror should be used to observe the flame
pattern at the tip of the nozzle. Any irregularities such
as burning to one side or pulsating flame patterns
should be corrected by changing the nozzle.
LIMIT CONTROL CHECK
After the furnace has been in operation for at least 15
minutes, restrict the return air supply by blocking the filters
or closing the return registers and allow the furnace to shut
down on High Limit. The burner will shut OFF but the main
blower should continue to run.
Remove the restriction and the burner should come back on
in a few minutes.
3.6 YEAR ROUND AIR CONDITIONING
The furnace is designed for use in conjunction with cooling
equipment, to provide year round air conditioning. The
blower has been sized for both heating and cooling;
however, the fan motor speed may need to be changed to
obtain the necessary cooling airflow.
3.7 HEATING
The blower speed is factory set to deliver the required
airflow at normal duct static pressure.
3.8 COOLING
The blower speed may be adjusted in the field to deliver the
required airflow for cooling applications, as outlined in
Table 4.
3.9 CONSTANT BLOWER SWITCH
This furnace is equipped with a constant low speed blower
option. Whenever the room thermostat is not calling for
heating or cooling, the blower will run on low speed in order
to provide air circulation. If this constant blower option is not
desired, the rocker switch on the side of the control box can
be used to turn it off.
4.0 MAINTENANCE
I
Before performing any service functions, make sure that I
all utilities are turned "OFF" upstream from the I
appliance, unless operations specifically require the I
power to be on. Failure to comply with this warning will I
cause a fire hazard and/or bodily harm.
I