I'll ask you guys. Which thermostat?


Senior Member
Which thermostat do you consider the best 2 way thermostat? It needs to have some degree of adjustable offset meaning that it does not start at 70 and stop at 71.
The RC-80 has adjustable run time minimums which will accomplish the same thing as adjustable offset. I have mine set to a minimum of 10 minutes for heating and 15 minutes for cooling.
OK next question. If you want to connect 2 of these do you have to get into that expensive rs485 stuff? If not do you have to connect them to different com ports?
I use telephone cable to connect to a com port. I have only 1 unit, but I would assume that using 2 ports would be the easiest.
I have 2 HAI RC-122's and connected up a couple of the HAI RC-80B's for a customer. All work perfectly, and the connection is simple, if not easier. 4 wires to the serial port, the second is just connected on top of the first to the same port.

Communications are quick and painless and better yet do not flood or use any x-10 commands.

I also think the plug-in for the HAI tstats is one of the best plug-ins's there is...

Get the new B version as it has a cool blue backlight... ;)
sbessel said:
.. the second is just connected on top of the first to the same port.
Does ti come with some type of "multi" connector? If not, how do you connect 2 devices to one com port?
First off it's not my plug-in, it is Alan's I just helped beta test it. (Alan also did the device manager, and is working on a new CADDX plug-in)

Second you have to make the PC connector/connection yourself. There is a pdf posted in the HS forum with the wiring diagram. It is a rather easy connection to make as there are only 4 wires for the communicating part of the tstat. And to add the second, third... you just connect the 4 tstat wires to the together (parallel)
OK last question hopefully. Where is the best place to buy. I looked and didn't see them on Martin's site.
You might want to contact Martin, I was under the impression he carried these units.
Martin got my last 2 for me, although it was not an item he stocked. This was a few months back.

My previous set cam from worthington.