Do you have the symbio app on your phone? is a new install or existing unit?
I don't, a coworker put in the device ID numbers. Also the mechanical rep confirmed that the unit was changed over to %RH method from the factory documented default Dew Point. That's what we wanted so I think we are good there.
Try setting the room temps 70*cooling, 65*heating leave RH set point at 40. if unit goes into heat mode you will not dehumidify.
It's in South Carolina, not much chance on flipping over to heating at the moment. I did convince them to increase the cooling setpoint from 68° to 73°, some mention of the psycometric chart and their priority on humidity. Temperature is a second for this area, just need people to not complain. So now with running both compressors flat out for a couple days straight the room is actually nailing the 40~46% range. No exhaust fan or OAD for this area. There is no chance it will get down to their desired 35% range in summer IMO.
You need reheats to work, Whats controlling the reheats? It would be nice to set reheats to monitor room temp setpoint.
This unit has Hot Gas Reheat. So in the above pictured mode it does appear to be tracking the room temp with HGR just fine. Just takes some careful maneuvering to get it in this mode that looks a lot like dehumidification but the unit calls it "cool".
can you manually turn on your reheats?
With a Trane integration? Of course not.
I would talk to Trane and make sure the unit is properly set for dehumidification.
We are working through that and RTFM too.
Trying to control RH with a DX RTU is not the best way. Depending on the outside air and RH it can be hard to dry down to below 40% without other means to control RH.
Why would a controls vendor be consulted on mechanical design, what could they possibly know.
For this unit I have the Application Guide, BACnet Integration Guide, Symbio 700 Application guide, Product Catalog, The IOM for Precedent, and the Symbio 700 User Guide.
These all total up to the magic number of 420 pages.
Out of all that though there's probably only three pages talking about dehumidification. It all makes sense in the manual, nothing crazy. In the picture below the only thing I'm questioning is the supply fan being 100% and the mode saying cool. The manual does say ", the supply fan operates at the minimum speed defined for the compressor stage. Compressors are increasingly staged to 100% capacity." So I guess it's going to be 100% against common advice that a lower fan speed dehumidifies better. But the nagging question is maybe they would ramp down if the unit would actually get the message and flip over to dehumidification mode?
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