MANAGE > 8 FAN COIL WITH 0/10V

Owned by Marco Serpelloni
Last updated: Sept 11, 2023
7 min read

To use this function, it is necessary to have at least firmware version 4.30 on the REG-DIN-8 and to use a RegConfig version 4.30 or later.

This logic was created with the aim to manage the speed of more than 8 fan coils in different rooms independently with a 0/10V.

Foreword

The REG System provides up to 8 Dehumidifier/Integration units, therefore, if in a system there are up to 8 fan coils, in as many rooms it is possible, for each zone, to manage a fan coil, using the Dehumidifiers page used as Integration, independently. For example, if there are 4 zones each with a fan coil for heating and cooling (or only cooling), each zone will be associated with a Dehumidifier in the Integration column:

In the Dehumidifier page, on each sub page D1, D2, D3, and D4 will be set:

  • Integration control “Active if requested” in summer and winter (if the room is to be both heated or cooled)

  • Valve control “Active if requested” if the Circuit is associated in the Dehumidifier page, if it is associated in the Zone page the Valve control may be left off

  • “Associated circuit” if managed from the Dehumidifiers page

  • The values in % of the low, medium, and high speeds of the Integration flow rates

Low, medium, or high speed of each fan coil depends on the integration offset set in Configuration 2:

Therefore, if the difference between the temperature read by the sensor of each zone and the set point set exceeds 1 K, the fan coil speed will be low, if it exceeds 2 K it will be medium and if it exceeds 3 K it will be high.

In the REGDIN OUTPUT page, the Analog Outputs to be connected to the 4 fan coils are the speeds of each dehumidifier (used as Integration) independent of each other:

If the fan coils are more than 8, it is no longer possible to follow this path.

Management > 8 fan coils by 0/10V

In this case, the zone determines its own speed (high/medium/low) always referring to the offset values in Configuration  / 2 (as in the case just illustrated): this evaluation is made by each zone autonomously and independently by making the difference between the value of the temperature read by the sensor associated with the zone and the room set point.

Then, each zone “borrows” from the Integrator to which it is connected (which in this case does not perform a proper function, but it simply “lends” settings) the value of the 0/10V output that corresponds to the speed it has already determined.

This value is transmitted on the 0/10 output associated with each zone (if the zone is not associated with an Integrator, the 0/10 of the zone transmits the room set point of that zone).

1. Definition of Integration offset in Configuration 2

As in the case with less than 8 fan coils, it is necessary to define integration offset in Configuration 2. Assume to use the same offset as in the previous example.

2. Definition of room and fan coil speed groups

Assume having 10 rooms, each of which is heated and cooled by 1 fan coil, which are associated with the zone in the Integration column:

The REG System can manage maximum 8 fan coil speed groups, as 8 are the available Dehumidifier/Integration units to rely on, therefore in the case at hand it is necessary to identify two pairs of room in which, reasonably, it is possible to manage with the same speed fan coils which are not in the same room, in the example are defined:

  • Living room and Hallway → Integration 1 (1 fan coil for each zone)

  • Kitchen → Integration 2 (1 fan coil)

  • Room 1 → Integration 3 (1 fan coil)

  • Room 2 → Integration 4 (1 fan coil)

  • Room 3 → Integration 5 (1 fan coil)

  • Dining Room → Integration 6 (1 fan coil)

  • Bathroom 1 e Bathroom 2 → Integration 7 (1 fan coil for each bathroom)

  • Studio → Integration 8 (1 fan coil)

Note

In this example it is not provided which dehumidifier/integration units can be used for anything else (e.g., a ventilation unit). But, if the available dehumidification/integration unit are less than 8, it is necessary to unify as much as possible the fan coil that have the same mapping between speed and volts. Therefore, if it is assumed that two dehumidification/integration units are already occupied, the 10 fan coils in the example could be grouped as follows:

  • Living room and Hall → Integration 1 (1 fan coil for each zone)

  • Kitchen → Integration 2 (1 fan coil)

  • Room 1 / 2 / 3 → Integration 3 (1 fan coil for each zone)

  • Bathroom 1 e Bathroom 2 → Integration 4 (1 fan coil for each zone)

  • Dining Room → Integration 5 (1 fan coil)

  • Studio → Integration 6 (1 fan coil)

It is reasonable to assume that rooms with the same intended use can share the same fan coil speed mapping.

3. Setting the fan coil speed groups

In the fan coil speed group of dehumidifier 1 on the Dehumidifier D1 page, it is only necessary to set:

  • The Air Flow Rate of the Integration in % from 0 to 100 in low, medium and high.

The Air Flow Rate can all be different depending on the requirements of the individual fan coil speed group. For example, in Room 1 the flow rates are lower than in the Living/Hall group:

If two zones rely on the same Integration unit, to take the 0/10 speed value, it is not certain that the speed at which the fan coils are operated are the same.

Let us take the example of the Living Room and Hall zone from the image; in point 2 we can notice that:

  • The temperature read by the sensor in the Living Room is 28,2°C with set point 27°C → delta = 1,2 K

  • The temperature read by the probe in the Hall is 30°C with set point 25,5°C → delta = 4,5 K

Therefore, the Living Room fan coil will run at low speed (4 V – 40%) because the delta is between 2 (medium speed offset) > 1,2 K > 1 K (low speed offset), whereas the Hall fan coil will run at high speed (9 V – 90%) because the delta is 4,5 K > 3 K (high speed offset).

4. Assigning 0/10V Outputs

On the REGDIN Outputs page, the Analog Outputs to be connected to the 10 fan coils are no longer the speeds of each dehumidifier (used as Integration), but the 0/10 value transmitted from each individual zone, corresponding to the 0/10 value of the speed (high/medium/low defined by the zone) taken from the integration unity associated with the same zone:

Therefore, on the REGDIN Outputs page, is associated with, for example:

  • UA1/0: set point zone 1 (Living Room) to be connected with the 0/10 V input of the fan coil of the Living Room

  • UA2/0: set point zone 2 (Kitchen) to be connected with the 0/10 V input of the fan coil in the Kitchen

  • UA1/1: set point zone 3 (Room 1) to be connected with the 0/10 V input of the fan coil in the Room 1

  • UA2/1: set point zone 4 (Room 2) to be connected with the 0/10 V input of the fan coil in the Room 2

A system of this type requires many 0/10 outputs (as many as the installed fan coils); therefore, it is advisable to use the REG-IOC modules, which have two 0/10V analogue outputs each and can be set in the IO/B Output page from number 92 to 99:

Warning

Currently, even if the NC (Not Configured) value is shown, the function is still active; to check the output voltage it is necessary to use a tester.

You can find an example preset attached:

Finally, if there is more than one fan coil in a room, it is enough to repeat what has been shown so far, simply associate the 0/10 value of the zone/room that has more fan coils with more analogue outputs (depending on how many fan coils there are).

For example, if the zone 10 (study) had 2 fan coils, the IO/B Output page would dedicate 2 analogue outputs to zone 10:

It is obvious that, in this case, since the room sensor is the same, UA2/94 e UA1/95 outputs will always have the same value and the two fan coils will work at the same speed.