Software Features And Logic; Heating Priorities; Staggered Start; Fresh Air Adjustment & Calibration On Economiser - Lennox Baltic BCK 020 Installation, Operating And Maintenance

control software features

Heating priorities

It is possible to set heating priorities depending on the
outdoor temperature.
For compressors: refer to the instructions 3611, 3612,
3613.
For electrical heater: refer to the instruction 3721.
Example:
It could be decided based on energy costs, that on a dual
fuel unit, it should run in heat pump mode when the
temperature is above 0°C and switch to gas burner below
that point.

Staggered start

After a power cut, the units can be made to restart one after
the other to prevent any current surge.
There is no need for a link between the units, they just
have to be given an address during commissioning and
they will restart 10 seconds x their "address number" after
the power is switched back on.
Example:
If a unit is given the address N°3 it will be switched-on 30
seconds (3 x 10sec) after the power is switched back on.
Fresh air adjustment and calibration on Economiser
The actual fresh air volume brought into the system is not
always proportional to the percentage of opening of the
fresh air damper. That is particularly true when the return
air duct system has been sized to produce excessive
pressure drop.
This often results in bringing into the system an excessive
amount of fresh air, hence increasing the running cost of
the system.
The control of fresh air is now achieved through the use of
three temperature sensors : One in the supply air flow, one
in the return air and one for the outdoor temperature.
Actual
Actual
Fresh
Required
Air
100%
80%
60%
40%
20%
20% 40%
Damper position
Using these three sensors, the Climatic50 will calculate
and memorise the exact percentage of fresh air for each
position of the damper.
T = T x %
supply air return air Return air
The calibration sequence will take place periodically when
all cooling or heating inputs are off. The instruction 3516
permits us to avoid the calibration.
60% 80% 100%
+ T x %
fresh air fresh air

Dynamic Defrost

Temp.
Coil
difference
Clean
between
coil and
outdoor
Defrost cycle start
Highest gradient
This new feature patented under INPI 91.033.063 allows
the unit to start the defrost cycle only when required.
This is achieved through the measurement of the
temperature difference between the coil and the outdoor.
The defrost will be initiated shortly after the Climatic50 has
located the largest gradient in the curve.
The defrost cycle ends when one of these two condition is
completed whichever comes first :
+ Three defrost cycles.
+ 6 minutes.

Alternate defrost

All dual circuits Baltic units have "Alternate Defrost" as a
standard feature.
When one circuit is going through a defrost cycle the
second circuit is running in heat pump mode. This
reduces the need for costly electric heater to maintain the
supply air temperature to an acceptable level of comfort
during the defrost cycles.
CO² Sensor
Where a CO² sensor is connected to the unit, the value of
the fresh air minimum is calculated according to the CO²
ratio. The value measured by the sensor can be read in
variable 2132.
Setpoint 3514 defines the number of ppm up to which the
fresh air minimum is still achieved.
Setpoint 3515 defines the number of ppm from which
100% fresh air is used.
Setpoint
0ppm
3514
IOM / ROOFTOP BALTIC Series - 0704-E Page 87
Coil
Coil
Freezing Frozen
Time
100%
CO2
Setpoint
200ppm
3515