TStat10 Multi Zones - Single Fan Coil Unit

Hello All!

I’m enjoying working with the Temco control system so far, and love to see all the discussion here in the forums.

My project has a hydronic fan coil unit suplying heat, cool and dehumidification. The fan coil unit is also supplying multiple hvac ductwork supplied zones (in my case 5 from this one unit)

It is a unit that has 4 pipes so it can do heating or cooling depending on the demand. It can also do dehumidification because it can have cool water to condense the water trapped in the humid air and then heat it back up as it passes the heating unit before leaving the fan coil unit.

So the question is, the Tstat10 can output a heat signal, a cool signal, a fan signal, a signal to my zone air dampers in the hvac piping, and a modulating signal to my modulating valves that will control the flow of hot or chilled water to the fan coil unit. HOWEVER, if I have 5 Tstat10 sending signals, I assume I will have to have them interconnected to a central controller and then the controller decide which signals to process first etc.

Anyone have experience in doing this?

Thanks in advance~

I think it would help to add more detail. Is there a specific reason why you would want to have 5 TStat10 units or are you feeling like that is what you have to do? How many signals are you controlling in total? switched plus analog? The TStat10 has 5 switched outputs and 2 analog outputs like (2-10V) so you could write a few control basic programs and run them on the TStat10 for controlling several of the operations. The TStat10 can run 16 small programs if needed. If you need more than 1 TStat10 because of the output counts, you could probably have them send commands between them with one acting like a master.


So I am using it in a commercial space where there are 5 rooms.

Each room needs its own tstat10

And each room also has its own hvac zone running off the same fan coil unit.

Does that make sense ? I can’t use one tstat to control all the room. So I need to use 5 and they will all communicate to the fan coil but I need a “order of operations” so the fan coil can process the signals in a specific order.

So if you have the TStat10 units already, that is a different story. You don’t need one for each from from the standpoint of the TStat10 units, but there many other reasons why you might want for each room.

That said, you probably don’t need a central controller. You could run a coordinating master application on one of the thermostats and have the other slave thermostats communicate with the master. The TStat10 is a wrapper around the T3 controller so you can write that logic on it in the T3000 software and send it to the master. The coordinator application could sequence the other thermostats that want heating/cooling by locking them out and enabling them according to your needs.

This would assume using reads and writes over a network shared by the thermostats.