Access 5.x

Heating/Cooling sequences > Starting order of heating/cooling


The order of sequence activation is set by assigning an order number for heating and cooling.


Configuration > Functions > Function activation > Heating/Cooling sequences >


As can be seen in the configuration example below:

  • In case of heating demand, the Exchanger (SEQ-B) will start first and Heating (SEQ-A) will follow second.
  • In case of cooling demand, the Exchanger (SEQ-B) will start first and the Cooling (SEQ-C) will follow second.



Position

Heating

Cooling

Start Heating

Start Cooling

Name

SEQ-A

2

Off

0%

0%

Heating

SEQ-B

1

1

0%

0%

Exchanger

SEQ-C

Off

2

0%

0%

Cooling

SEQ-D

Off

Off

0%

0%

Recirculation 1

SEQ-E

Off

Off

0%

0%

Recirculation 2

SEQ-F

Off

Off

0%

0%

Fan heating/cooling

SEQ-G

Off

Off

0%

0%

Heating 2

SEQ-H

Off

Off

0%

0%

Cooling 2

SEQ-I

Off

Off

0%

0%

Exchanger extract

SEQ-J

Off

Off

0%

0%

Extra heating/cooling capacity





Sequence overlapping or dead band can be set by adjusting “Start Heating” and “Start Cooling” sequence parameters.

The adjustable range is -100% .. +100%.

A negative starting point will create sequence overlap while a positive starting point will delay the start of the selected sequence.



Position

Heating

Cooling

Start Heating

Start Cooling

Name

SEQ-A

2

Off

50% 0%

0%

Heating

SEQ-B

1

1

0%

0%

Exchanger

SEQ-C

Off

2

0%

-25% 0%

Cooling

SEQ-D

Off

Off

0%

0%

Recirculation 1

SEQ-E

Off

Off

0%

0%

Recirculation 2

SEQ-F

Off

Off

0%

0%

Fan heating/cooling

SEQ-G

Off

Off

0%

0%

Heating 2

SEQ-H

Off

Off

0%

0%

Cooling 2

SEQ-I

Off

Off

0%

0%

Exchanger extract

SEQ-J

Off

Off

0%

0%

Extra heating/cooling capacity




In the initiation phase of the air handling unit, a specialized temperature control regimen is applied, deviating from the standard sequence order:


During default startup, the exchanger sequence initiates regulation from 100% to 0%, contrary to other sequences. This approach expedites the attainment of the setpoint temperature and minimizes the risk of thermal shock to internal components. If necessary, the operation of the selected sequence can be modified to the conventional 0% to 100% range or any other specified sequence.


A similar inversion of the control signal during startup can be configured for an additional sequence. By default, this configuration is applied to the Heating sequence when the outdoor temperature falls below 3°C. This adjustment facilitates the achievement of a comfortable temperature and safeguards components against potentially hazardous low air temperatures.


Start up related settings of the heating sequences









Configuration > Functions > Function activation > Heating/Cooling sequence setup





Position

Heating

Cooling

Start heating

Start cooling

Name      

Note





SEQ-A

2

Off

0%

0%

Heating >

2nd Heating sequence









SEQ-B

1

1

0%

0%

Exchanger >

1st Heating sequence









SEQ-C

Off

2

0%

0%

Cooling >






SEQ-D

Off

Off

0%

0%

Recirculation 1 >

Can be configured by assigning the sequence start number





SEQ-E

Off

Off

0%

0%

Recirculation 2 >





SEQ-F

Off

Off

0%

0%

Fan setpoint comp >





SEQ-G

Off

Off

0%

0%

Heating 2 >





SEQ-H

Off

Off

0%

0%

Cooling 2 >





SEQ-I

Off

Off

0%

0%

Exchanger extract >





SEQ-J

3

Off

0%

0%

External h/c capacity >

3rd Heating sequence










Variable

Available options & Selection

Note





At start up begin temperature control at 100% in

| Heating 1 | Heating 2 |… |

Heating 1 = the 1st heating sequence









Warm start up if outdoor temperature <

[3] oC

Heating 2 = the 2nd heating sequence will activate at startup if outdoor temperature is bellow limit





If warm start up begin temperature control at 100% in

| Heating 1 | Heating 2 |… |