ᐅ Central room temperature controller for the fan coil unit (FCU) of the underfloor heating system

T_im_Norden schrieb:

Say goodbye to the idea that the heat pump heats individual rooms.

Imagine your entire house with the rooms as one large water circuit.

Each room has an adjustable access point that controls how much water flows through it in a given time.

The whole circuit is heated to a set temperature.

To reach the desired temperature in a room, you need to allow a certain volume of water to flow through it, depending on the room size.

If all rooms are the same size, this is simple—you just let the same amount of water flow everywhere.

But rooms are usually different sizes, so you have to adjust the water volume for each room accordingly.

You control this via the access point (the manifold for the underfloor heating, where you can set the flow rate).

Unfortunately, some rooms cannot accommodate enough water to reach the desired temperature (especially bathrooms, since they are small and require higher temperatures).

You can either create more space for water (reduce the spacing of the pipes or use wall heating) or increase the water temperature.

Increasing the water temperature (the well-known flow temperature) does provide the needed warmth in the bathroom, but other rooms will also become warmer.

So, you have to reduce the water volume there until you reach the desired temperature.

This process is called hydraulic balancing.

Now the problem arises that at low outdoor temperatures, the heat supply may no longer be sufficient.

You could increase the water volume in each room, but then you would have to readjust everything to get the balance right again, and you would still be limited by smaller rooms where not more water can flow.

However, our heating system knows from the outdoor sensor when the temperature outside drops.

So, it increases the flow temperature to compensate.

Since all rooms were previously adjusted to their correct temperature during the hydraulic balancing, this works.

This is the heating curve of the system; it stores how much the flow temperature must change as the outdoor temperature varies.

This is a simplified explanation but represents the basic function.

pagoni2020 schrieb:

Thank you for this detailed explanation.
I read that it is possible to get an exemption from installing the -ERR- for a fee. So, it would make sense to obtain this exemption and omit the ERR entirely, right?