Thermostat installation question

[Niner National]

So I'm replacing an old analog thermostat with a new digital/programmable one, but I've encountered an issue with wiring.

 

Most of the wires from the old one had matching colors/codes on the new one, but I have two wires that I'm not sure about.

 

My white wire was plugged into the W2 connector on the old thermostat and my black wire was plugged into the E connector.

 

On the new thermostat, the W2 and E connector are one in the same. Do I plug both wires into that connector, does one wire go unused, or does one of them go in one of the other connectors that are open?

 

Can anyone here help? I haven't been able to find a definitive answer anywhere.

[cookinbrak]

Plug the white wire into W1. There should be a wiring diagram with the new thermostat.

 

 

Also, check your dipswitches and set them.

[pstall]

Ehow or youtube video this. Prob solved

Sent from my SPH-L710 using CarolinaHuddle mobile app

[Niner National]

Ehow or youtube video this. Prob solved

Sent from my SPH-L710 using CarolinaHuddle mobile app

I've tried, haven't found any situations just like mine.

[Niner National]

Plug the white wire into W1. There should be a wiring diagram with the new thermostat.

 

 

Also, check your dipswitches and set them.

I plugged the white wire into w1 and left the black one out. My friend that does HVAC wiring for a living told me to do this, but nothing worked.

 

The wiring diagram for the unit also showed the black wire not being used.

 

This is so damn frustrating. The box said it would take 5 minutes  :(

[Anybodyhome]

1. If your old thermostat was a 5-wire and you purchased a 6-wire, it may not be compatible.

2. Is there a "Not Used" terminal to attach the black wire?

3. Too late now, but you should have labeled each wire and how it was attached to the old thermostat... big help.

 

What is the brand and model of the one you bought and how many wires are coming out of the wall?

 

 

[Niner National]

1. If your old thermostat was a 5-wire and you purchased a 6-wire, it may not be compatible.

2. Is there a "Not Used" terminal to attach the black wire?

3. Too late now, but you should have labeled each wire and how it was attached to the old thermostat... big help.

 

What is the brand and model of the one you bought and how many wires are coming out of the wall?

I have pictures of what every wire went into. Nothing was labeled beyond that. I have 8 wires total. In the original thermostat they were wired like this:

 

Red went into R

Yellow went into Y

Green went into G

Blue went into X

Black went into E

White went into W2

Orange went into O

Brown was not attached to anything.

 

On the new thermostat I have:

 

Red attached to R / RC with a jumper

Yellow in Y

Green in G

Blue in C (common wire)

Orange in O

Brown not used.

 

The black and white wires are where my issue comes in. I put the white back into the W2 terminal, but that terminal is also labeled as E. I read that I could put both into the W2 terminal and it would work the same (on an HVAC QA site where professionals answer questions). That did not work either.

 

I've been sure to kill all the breakers to the HVAC system before so that I don't fry anything.

[Vampire the buffet slayer]

Is it a split system or a package unit?

Gas or electric?

[Vampire the buffet slayer]

Have you used a volt meter to determine whether the blue is the common?

In some older wiring the blue wasnt always the common.

[Anybodyhome]

Blue is sometimes used as the emergency heating and is not always the common.

 

The other thing you can do is open the inspection cover on the air handler and see how it's wired since the t-stat goes to the air handler.

[Anybodyhome]

Try this out:

 

[KillerKat]

I did this a year and a half ago. Still have my notes.

Black to X2

White to W1

Yellow to Yellow

Green to Green

Orange to Orange

Red to Red

Blue to Blue

[KillerKat]

Be careful that you have the wiring right before turning power back on the thermostat. You can blow the transformer like I did and your place will smell like burned metal.

[Niner National]

even though I was careful about the breakers, I still blew a fuse. I got it working though after putting a new fuse in. Thanks for the help everyone.