In fairness to all, we don't discuss pricing on the Wall. Thanks for your cooperation.
Digital thermostat on an incremetal PTAC (type K) with electromechanical contorl box
I have an "incremental PTAC unit", a McQuay type K (design A), with DX cooling and a steam heat coil.
In cooling mode, the compressor and the fan are controlled by the Tstat.
heating mode, only the blower fan is controlled by the Tstat. I do not
have a shut-off valve so the steam coil is energized even if the Tstat
doesn't call for heat.
The control box is currently unit-mounted.
like to install a programmable thermostat on it (a NEST or something else internet-enabled). A McQuay service rep
told me the current control box is electromechanical and that in order to
wire in a digital thermostat I would need a need new control box (~$500) with digital inputs. I am definitely not interested in paying $750 per PTAC for that.
I feel like there might be another way to do it myself but I am not very familiar with exactly how these things work.
I have attached the wiring diagram for my PTAC unit, as well as a couple of pictures of the PTAC and the control box.
Has anyone done something similar before? Can you give me some pointers?
Any insight or information you can provide would be very helpful.
Thanks a lot!