Dettson ADVANTAGE SUPXX-A120D12, Инструкции по установке и руководство для владельца

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3.3 OPERATING SEQUENCE
3.3.1 Heating mode
1. The thermostat closes the R-W1 circuit (24 VAC),
thereby sending a 24 VAC signal to the blower relay
and the sequencer board.
The board will then
activate all the first stage relays with a delay of 3
seconds between each element. The motor relay
will be activated, which will start the blower on the
first stage heating speed.
2. The thermostat closes the R-W2 circuit (24 VAC),
thereby sending a 24 VAC signal to the blower
relay and the sequencer board.
The board will
then activate all the first and second stage relays
with a delay of 3 seconds between each element.
The motor relay will be activated, which will start
the blower on the second stage maximum heating
speed.
3. The deactivation of either mode will result in the
deactivation of the corresponding relays with a
delay of 0.5 second between each element.
3.3.2 Cooling Mode
1. The thermostat closes the R-G circuit, thereby
activating the 24 VAC relay. The blower starts up
to cooling speed.
2. The thermostat closes the R-Y contact, thereby
activating the compressor relay of the air
conditioner.
3.3.3 Continuous fan speed
Activating the “Fan” switch on the thermostat will engage
only the blower at cooling speed.
3.4 AIRFLOW VERIFICATION
Verify the airflow by taking readings of the following
points, while the elements are in heating mode:
a) Total amperage of all the heating elements;
b) Voltage at the furnace;
c) Supply air temperature. The point of the reading
must not be affected by radiant heat from the
elements;
d) Return air temperature.
From these readings, one can arrive at an approximate
calculation of the average airflow.
To do that, the
following formula should be used:
Liter/s
=
0 . 82
× amps. × volts
Diff. temperature °C
CFM
=
3 . 1
× amps. × volts
Diff. temperature °F
Tables 5 and 6 show estimated airflows for various
temperature rises.
3.4.1 Supply Air Temperature Rise Test
1. Operate the unit at maximum power for at least 10
minutes;
2. Measure the air temperature in the return air
plenum;
3. Measure the air temperature in the largest trunk
coming off the supply air plenum, just outside the
range of radiant heat from the heat exchanger. 0.3
m (12”) from the plenum of the main take-off is
usually sufficient;
4. Calculate the temperature rise by subtracting
the return air temperature from the supply air
temperature.
If the temperature rise exceeds the temperature specified
in Table 2 and Table 3, change to the next higher blower
speed tap, until the temperature rise falls to the target
or below.
If the excessive temperature rise cannot
be reduced by increasing fan speed, investigate for
ductwork obstructions or dirty and improper air filter.
CAUTION
It is important to check the airflow and to
ascertain that the unit does not operate above
the temperatures specified in the Technical
Specifications (Table 2).
This is particularly
important if a cooling coil or a heat pump has been
installed in the ducts.
Hi-Limit thermal protectors should never need
to engage during the normal functioning of the
appliance. They are strictly designed to engage
during the improper functioning of the blower or
when the filter was improperly maintained.
3.4.2 High limit verification
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 electric heaters must deactivate themselves before
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