Dettson SUPREME SUP10-M2401A, Installation Instructions And Homeowner'S Manual

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The 24 VAC relay of the heating speed is also activated
and heating blower speed start.
3.3.2. Cooling mode
1. The thermostat closes the R-G circuit, thereby activating
the 24 VAC R-1 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
The blower will also start up to cooling speed by way of the
“Fan” switch on the thermostat.
3.4 AIRFLOW VERIFICATION
Verify the airflow by taking readings of the following points,
while the elements are in the 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:
0.82 x amps. x volts
Liter/s= -------------------------
Diff.
temperature ˚ C
3.1 x amps. x volts
CFM = ------------------------
Diff.
temperature ˚ F
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. Measuring 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. The temperature rise is calculated by subtracting the
return air temperature from the supply air temperature.
If the temperature rise exceeds the temperature specified in
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 one by one
before the warm air temperature exceeds 200
˚ F.
Remove the obstruction and the elements should restart
after a few minutes.
4.0 MAINTENANCE
WARNING
Electrical shock hazard.
Turn OFF power to the furnace before any disassembly
or servicing.
Failure to do so can result in death, bodily injury and/or
property damage.
Preventive maintenance is the best way to avoid
unnecessary expense and inconvenience. Have your
heating system inspected by a qualified service technician at
regular intervals. Do not attempt to repair the furnace or its
controls. Call a qualified service technician.
Before calling for repair service, check the following points:
1. Check fuses or the circuit breaker;
2. Check if the 15 A circuit breaker on the furnace is
disengaged;
3. Set the thermostat higher than room temperature. If the
unit does not start up, cut the power and call la qualified
service technician.
When calling for service or ordering a replacement part,
specify the model and serial number of your appliance.
4.1 AIR FILTER
The filter supplied with the unit is the disposable type and
should be replaced twice a year. The presence of animal
hair, dust, etc. may necessitate more frequent changes.
Dirty filters have an adverse effect on the performance of the
central heating system.
4.2 MOTOR LUBRICATION
Do not lubricate the blower motor, since it is permanently
lubricated.