replaced thermostat.. need help..


Ok so I took a thermostat out..
honeywell... it had 4 wires that go back to my hvac unit..

Red
Green
White
Blue

Thermostat
Red went to R
Green went to G
White went to W
Blue went to Y ( I looked and it is Y on both ends.. 4 conductor wire so they used the blue...)

anyway..
my new thermostat is
intermatic z-wave ca8900

they want me to hookup
Red to R
Green to G
White to W
then they throw a +C to C

well I have the hvac unit hooked up the way my old system was and it works... everything works.. but the C is 24vac to keep the thermostat running.... so instead it is eating up batteries...

what do I do?
just run a new wire back and connect C to the controller board of C????

on the controller board there is everything I listed above with an additional...

C - white wire
then a red wire from that pair goes to Y

so how do I get 24vac to the thermostat???

Thanks
Jeff

 

Never heard of this brand.

Do you have an extra wire tucked behind the wall, or cut back? If you have an extra wire, use that color, and tie it to C at the t-stat, and C at the furnace.

That wire is going to your A/C unit outside.

 

it is a z-wave home automation thermostat...



I will check.... however if I do not have an extra wire it is safe to just go C to C.... so I will need to get another wire to the unit..... ok.....

Will try that...
thanks
Jeff

 

If you don't have the wire, pull a new 18-7 wire up.

 

you are correct.. not that I doubted you..

I followed the red/white 2 wire and it goes to my ac unit outside...

so red goes to Y
and white goes to C

is C for common?

and red is hot?

Im thinking that is my problem... im going to run a enw wire tonight....

I believe I just dont have a ground for the thermostat....

 

also I have a spool of cat5 wire.. would that be ok for 24vac?

it is 4 pair (8 wire).....

 

Yes, C is common.

Yes


There's no ground, unless you mean Common?

No, the CAT5 is too light, has to be 18 gauge,, CAT5 is 24.

 

thanks a bunch....

gonna go to lowes on my way home....

 

well I did it.. works like a charm... thanks!
~Jeff

 

Thanks for the update, and glad it's working for ya.