I currently have a Carrier TSTATCCSHP01 which I am replacing with a Crestron CHV-TSTATRF.

On the Carrier, the wiring is:
(W) is connected to white wire
(G) is connected to green wire
(R) is connected to red wire
(C) is connected to black wire
(Y) is connected to yellow wire
(O) is connected to orange wire

So, I simply brought those connections over to the Crestron thermostat. I tried multiple wiring setups as per the Crestron manual -- all with the same result:

Fan blows air, but it's not cool air. The thermostat is making the cool call, but apparently it's not cooling. I don't know what I'm doing wrong. Any ideas?

Also, I should mention there is both a blue and black wire (unstripped) in the bundle which is apparently unused (at least by the original Carrier thermostat).

You couldn't have:

There is an Rc and Rh in the Crestron.

Connect Rc and Rh at the Crestron unit and connect the combination to R.

You failed to mention where it worked in heat, which I suppose it does.

Yes, sorry, I did forget to mention that -- yes, heat does work. I have tried with a jumper between RC and RH but it made no difference, still no cool air.

In regards to the Crestron manual, I've tried the wire configurations for "Heat-Cool Application with Integrated Control Unit" and "Cool Only Application". Both of which yield the same results.

After you initially apply power, there could be up to a 5 minute delay before the compressor kicks in. This is part of the anti-short cycling protection. The thermostat usually tales care of the delay.

One for initial power up and one when the modes are changed.

O or B controls the mode.

Check to mke sure this is set up as a heat pump in the Crestron manual.


I haven't read the manual yet. Only glanced at what appeared relevant.

A Heat Pump (HP)? I shouldn't be setting this up as a Heat/Cool (HC) system? I thought a Heat Pump required outdoor temperature sensors, etc. AFAIK, my system does not.

That may be the whole problem here..

This is how I currently have it connected:
(C) Black Wire
(W) White Wire
(O) Orange Wire
(RC/RH Jumpered) Red Wire
(G) Green Wire
(Y) Yellow Wire

It's currently in Heat/Cool mode in the thermostat setup. You're saying I should set it to Heat Pump?

I set the mode to HP, and I'll be damned if it didn't start cooling right away.

Apparently I know as much about HVAC system as I do quantum mechanics.

KeepItSimpleStupid, thank you for your help. I apparently have some reading to do!

In a heat pump and electric heat the thermostat controls the operation of the fan. For a gas furnace, the furnace controls the fan. More interesting is that the manul. Fan control is powerd from Rc.

Compressors, whether it be heatpumps or AC units need to REST for about 2-5 minutes before they are turned on after the are turned off. If they are not allowed to rest, the breakers blow violently because the pressure in the lines are very high like 250 PSI or more. The two to 5 minutes allows the pressures to relax to about 80 PSI depending on refrigerant so they are not starting under load.

Initially when the system is commissioned which is the same as if you had a very quick power failure, like you might have in a storm, the system has to delay operating for the 2-5 minute interval because it doesn't know if it was on or off. So, just powering it up and not doing anything for 5 minutes is enough. Then when you turn it on to cool it comes on right away.