Thermostatic Controls - New thermostat, 4 wire?

I am installing a Venstar Thermostat (http://www.smarthome.com/2491T1/Venstar-Thermostat-INSTEON-Remote-Control-Thermostat-1-Day-Programmable/p.aspx) replacing an old 1993 thermostat controlling a heat pump. I have basically 4 wires coming down and the old thermostat had this configuration:


Red wire <--> Rc
White wire <--> O
Green wire <--> G
Yellow wire <--> Y and W
Blue wire (capped)

On the new thermostat, there are only instructions for 6 wire...


http://www.leerogers.com/downloads/new.png

What am I missing? I am not sure how to wire. Any help would be appreciated.

Thanks.

Old---------New
Rc----Red---R
O----White---O
G----Green---G
Y----Yellow---Y

make sure set the jumper. not sure, let me know.

What is your back up heat? (See it not hooked up on the old t-stat)

Thanks Jay for such a quick response. I wish it was that easy :-) I tried that and the thermostat wont power on at all. I have two units so I tried both thermostats I bought on this to make sure it wasn't a bad unit.

I have installed other thermostats and this one was odd to me since the yellow wire went to 'Y' and to 'W'. Also, I can't tell if Rc and Rh may be jumpered on the old thermostat?

I have the jumpers set to ELEC (FAN), HP (I assume Heat Pump), and I tried both O and B.

The new installation guide is here (http://www.smarthome.com/manuals/30410a_install.pdf).

As far as the back up heat, I have never heard of it. I am in Phoenix so maybe we don't need it? :-)

What happens when you touch R and G wire?

Give me the make and model # of the air handler/furnace.

Thanks for your help Jay.

I have two units...

Carrier FA4ANF042 and FA4ANF036. Both of the old thermostats are wired the same.

I tested jumping R and G and the fan does come on.

We know the unit has power, did you hook up C or use battery?

I don't see that these thermostats have batteries... I tried connecting the capped blue wire to C on the thermostat with no luck. Do I need to jumper the R to somewhere else to power?

Thanks for your help.

Was the blue hooked up to C at the furnace?

Unfortunately, I am not the person crawling around the attic hooking up wires my unit so I may have to bring someone in to install these for me. I thought it would be a simple change over but it looks like more of a major move. :-(

The manual isn't clear about saying if C has to be hooked up or not.. But it does show it hooked up, so that kinda tells me you have to get C wired up to light up the display.