TStat8 for use on a heat pump

I just ordered a couple of Tstat8’s for testing. The website show that it can be used on a heat pump. I have read through the devices literature and cannot locate any reference to program setting for a heat pump. Are there any example of program settings for heat pump use?

There should be a few examples in this forum… if not I can do one for you now. Send a list of the IO and a rough sequence and I’ll whip up a config file for you. The Tstat10 is actually the way to go for new projects. There were so many edge cases for the Tstat8 that it was getting unwieldy to support all the custom firmware this required. Now with the fully programmable Tstat10 you can do your own custom applications on the fly.

If you’d like to exchange for the Tstat10 we can arrange that, just send us an email.

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Exchanging it for the Tstat10 sounds like a good idea. Who do I send the email to? Hopefully they haven’t shipped yet.

You can find email coordinates on the website, about us, etc. Also when you order an item you get some good coordinates. We monitor them closely.

I am trying to configure a TStat8 8 for heat pump application. We have 70 of these on a new project.
I am using the temp sensor to control the following with the thermostat setpoint.
internal temp is the temp sensor.
DO-1 Fan
DO-2 Heat 1
DO-3 Cool 1
DO-4 Reversing Valve
DO-5 Cool 2

Can you send me a configuration file for this?

I will need to work on this with you when I get to my PC in a day. The general idea is the same as the other examples on this forum, search around for Tstat8 heat cool example and it will turn up. Set the number of heating stages as 1 and cool as 2, then fill in the outputs to be on or off as appropriate. The only twist is my earlier examples don’t have the reversing valve, depending on if its on for heat or cool, have it on in the appropriate stages along with the heat and cool stages.

Give it a try and report back here, I can assist more soon.

We are not successful yet on controlling with the tatat8 a water source heat pump.
The condenser water valve must be on and the W1 must be on in order for the heat to work.
The condenser water valve must be on also to cool.
The only time the valve will close is if the unit is off.

What we are doing is interlocking and opening the valve with the G .
Then as we need cool or reversing valve for heat the valve is open.

Is there a sample PID setting for this?

When I enter water source heat pump in the forum nothing comes up.

Thank you

Could I see a screen shot of your PID output table settigns. Forst we need to make sure you have the correct number of cooling and heating stages set up. then its just a matter of toggling the right outputs on for each stage of heating, cooling and ‘coasting’

Sure I’m back today on site.
Also, i should be able to control the outputs later via BACnet correct? Priority 10?

Controlling the outputs of a Tstat8 could be done but writing to the outputs directly with priority array is a bit complicated way to accomplish that. Come to think of it, the Tstat8 doesn’t support priority array. One way you could do this is to put the outputs in manual mode from the T3000 interface and then write to the outputs from your master.

A much simpler method, the way most people will want to consider integrating the Tstat8 into various environments is to manage the setpoints as Bacnet Av’s. Your external master controller can write to them directly. Write the occupied and unoccupied setpoints, and then manage the schedule as the usual Bacnet object.

Maurice,

I am trying to access the thermostats Tstat8 using a remote connection.

I have routed 47808 to my internal IP from outside.

We can see all other devices that are on this network except the TSTAT8.

Do you have any example of how you use the t3000 software from outside using an internal BACnet router?

Maybe a setup example of the remote connection?

Is it only UDP 47808 and 502 port?

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I need to run the same test on how you use it in order to explore it further.
I’ll get back to you after testing.