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Smarty 2R VE / 2R VE plus
www.salda.lt
This function is designed to activate/deactivate the boost ventilation function or preferred combination of fan speeds by means of an external contactor.
The function indicates a type of a signal to be sent to the input and components controlled by it. Possible combinations of signal types and functions:
•
Not used.
•
On/off
. Selected fan speed combination is activated. Function is on when contactor is on.
• Button click. Selected fan speed combination is activated. Function is activated when it receives an impulse. It is deactivated when it receives
the impulse again.
•
On/off.
Boost ventilation function is controlled. Function is on when contactor is on. If the boost ventilation function is not terminated by means of
this function within the boost ventilation time limit, force shutdown is used after the time expires.
• Button click. Boost ventilation function is controlled. Function is activated when it receives an impulse. It is deactivated when it receives the
impulse again.
• If the boost ventilation function is not terminated by means of this function within the boost ventilation time limit, force shutdown is used after the
time expires.
It is also indicated whether boost ventilation will be activated or combination of fan speeds is preferred, i.e. it is possible to indicate preferred supply
and extract air fan speeds individually.
Cold - Heat Recuperation
Cold-heat recovery function is designed to control a heat exchanger. Its power is controlled:
1. Together with a plate heat exchanger a bypass damper is used. When it is closed, the heat exchanger is used at its full capacity. Its power is
reduced by opening the damper.
2. Using a rotary heat exchanger power is controlled by changing its rotating speed or interval. When the rotor rotates at its full speed, the heat
exchanger is used at its full capacity. Power is reduced by reducing rotating speed or increasing an interval.
Depending on the outdoor temperature, the heat exchanger can be used to heat or to cool. If the temperature outside is lower than the temperature
in the room, the heat exchanger pre-heats outdoor air by using the heat of the room. If the temperature in the room is lower than the temperature
outside, the heat exchanger cools down outdoor air by using air of the room. The power of a heat exchanger is reduced to the minimum when the
required supply air temperature is the same as the temperature outdoors. The higher the difference between required and supplied air temperatures,
the higher power usage of the heat exchanger. Other heating/cooling components can be activated only when the heat exchanger operates at its
maximum capacity.
The type of a heat exchanger suitable for this function is indicated in SERVICE › HEAT EXCHANGER, while coefficients of PID controller are indicated
in ADJUSTER › PID CONTROLLERS ADJUSTING window.
PID controller output rate is determined for rotor or bypass damper, at which they start operating.
• If rotor is controlled by 0.10 V signal, it won‘t rotate at a low voltage and the engine heats, thus minimal control signal output is limited. If On/Off
rotary heat exchanger is used, PID percentage for activating the rotor is indicated in the window SERVICE › HEAT EXCHANGER.
• If bypass damper opens just some percent, noise may occur, so minimal opening of the damper is limited and this limit is also applied when the
damper is almost opened. Where the plate heat exchanger with a three-position bypass damper is used, the time it takes for a bypass damper to open
is indicated in the window SERVICE › HEAT EXCHANGER.
Heat Exchanger Anti-Frost Protection
This protection is designed to protect the heat exchanger against accumulation of ice, which can damage the structure of the heat exchanger. It is
configured in the service environment window SERVICE › HEAT EXCHANGER.
Activation / deactivation of the protection is performed taking into account:
• the indicated outdoor air temperature;
• the indicated extract air temperature;
• the indicated extract air and calculated freezing point temperature difference (the latter is calculated according to the outside temperature, room
temperature and humidity);
• the pressure relay.
Possible means of protection (performed in a sequential order as indicated):
• reduction of the supplied air flow (-30 %);
• recirculation of the outdoors and exhaust air;
• heating of the outdoors air by pre-heater;
• opening of the bypass damper or slowing down the rotor;
• stopping of the device (taking into account the temperature of the supplied air);
• stopping of the device, if safety zone is not reached for a determined time (two cycles);
• stopping of the device taking into account the critical outdoors air temperature (stopped after 30 seconds).
Conditions and means of protection can be activated by choice. The time of moving from one mean to the other is also indicated. If at least one acti-
vation condition is met, the protection is activated and a message is displayed. The process is started from the measures using the least amount of
energy, i.e. (if allowed) the flow of the supplied air is reduced. If this does not help during the indicated time, the next measure is applied. The sequence
of moving from one protection measure to another shall be followed. For a protection with a pre-heater, a position of the outdoors air sensor regarding
the pre-heater, is indicated (before/after). If the sensor is indicated before the pre-heater, the device is not stopped if the required outdoors temperature
is not reached with the pre-heater.
Recirculation of the outdoors and exhaust air is economical and effective protection, but it provides extracted air into the flow of the supplied air.
Pre-heater of the outdoors air may be used in all its capacity or just to maintain the determined temperature. If the second variant is selected, then the
activated protection at first turns on the pre-heater to operate at full capacity for a determined time period, and then it helps to maintain the indicated
deactivation temperature.
If a plate heat exchanger with a bypass damper is used, a heater of the supplied air must be installed. By opening the damper the flow of the cold air
passing the heat exchanger is reduced but the supplied air, which has to be warmed by the heater, is cooled down. This protection slowly opens the
bypass damper, until activation conditions are met. When they are met, damper is stopped for 5 min. and then it is closed slowly. Slow closing also
happens, when the temperature of the supplied air drops below the allowed limit.
