Question about Honeywell CT87B ROUND HEATING&COOLING MECHANICAL THERMOSTAT - WHITE Heater

1 Answer

Replacing a thermostat

Im replacing my thermostat and the one im replacing the old one with has different colored wires and a little different and newer all together. Just wanted to make sure a had it hooked up correctly before plugging it in and i dont have any instructions to use. i think its a honeywell but not sure. All i have is this info. the product i selected below is not my thermostat but couldnt locate it in your list.
0546 TYPE
LR27935 1F56-486
CLASS 2 153-4242
PART NUMBER 1147165

Posted by on

  • rwblue Sep 07, 2008


    I am replacing my old thermostat with a Honeywell RTH3100c, but the wires layout is different. Information about the new and old product.




    Old

    H4/Honeywell?

    0546 TYPE
    LR27935 1F56-486
    CLASS 2 153-4242
    PART NUMBER 1147165


    Connection

    White – G Blue – Y

    Yellow – Y Red - RC à RH

    Green – G No wire A and B

    New

    Honeywell

    RTH3100C

  • SHARCNET-USA
    SHARCNET-USA May 11, 2010

    How many wires do you have coming out of the wall and what are their colors? Do you know what the functions are for each color?

×

1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Superstar:

    An expert that got 20 achievements.

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

  • Master
  • 1,420 Answers

Typically if you are replacing a heat only thermostat you will have two or three wires. On the old thermostat these wires will be attached to terminals marked "R", "W" and maybe "G". Document what color wires goes to which terminal and transpose these to the new thermostat. If you have a heat and cool thermostat, you will have two or three more wires and connected to terminals labeled "C", "B" and "Y". Again, transpose these wires to the new thermostat as best you can.

Posted on Feb 12, 2008

1 Suggested Answer

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
goodluck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

I bought a replacement oxygen sensor providing instructions for new part wire color connections. The old and original part bring different color of wires. What should I do?


Return the Sensor

You want an OEM replacement
that is exactly like your old one

Screw it in Tighten a little
and plug in wire connector

Mar 16, 2011 | Chrysler Pacifica Cars & Trucks

1 Answer

I bought a honerwell regular digital thermostat and changed it trying to follow directions the 4 (four) wires coming out ofn wall and that were connected to old thermo were red, black, yellow and white. ...


Wiring color to Thermostat Depending on what thermostat youhave and existing wires. Typically red and white are for heat and yellow andgreen are for cooling. On base of thermostat there should be initials stampedto identify wires by color. R. W. Y. G. Possible Rc. and Rh if so for most usesyou need to jumper these two together. You may have a blue wire instead ofyellow or green. If so just hook blue to y or g. Hope this helps you. Thanks.

Jan 05, 2011 | Heating & Cooling

1 Answer

Want to replace a T874R1434 thermostat with aux heat with a visionpro th8000. Have a blue wire connected to the B terminal on old thermostat and what looks like a brown wire connected to the X terminal on...


Its kinda difficult to know exactly what the wires could go to considering its all in the way the technician decided to hook them up and everybody has different ideas. I can tell you the most common use of the colors and see if that helps. Depending on how many wires your system has,
Red=Power
White=Heat
Yellow=Cooling/AC
Green=Fan
Blue=Common/Ground
Brown=Heat

Black and Orange wires alternate a lot with different HVAC techs, but usually go to a heat pump system outside.

The best way to get a grip on what wires go where is to look inside the furnace and see where they go. If you have a electrical board, it gets a lot easier, and the back of the furnace door usually has wiring diagrams that are pretty up front about the wiring. Just keep in mind that the wires could have been changed from the thermostat to the furnace, but you can usually tell if the wires seem different. Hope this helps some and good luck!

Jun 13, 2010 | Ruud UBHC Air Conditioner

1 Answer

How do i know i wired my thermostat right


If the thermostat only has two wires that connect to it then your ok...

Apr 20, 2010 | Whirlpool Dryers

1 Answer

I am replacing an old Lennox thermostat with a new Lux DMH110 digital thermostat. My furnace(oil) has only two wires on the thermostat(heat only). I connected the wires according to directions of new...


Make sure on the furnace that you have the same colored wires connected at the thermostat to R and W. Check for good connections at both locations. You can always test to make sure the unit fires by crossing the two wires together. If the unit fires, you have a bad thermostat.

Feb 17, 2010 | Honeywell Programmable Thermostat Heater

1 Answer

Three wires not marked for new Thermostat!


You will need to go to the heating system and see what color wires are hooked to that. Typically the black and white wires will be used unless they used another color due to a bad wire. Hook the colored wires to the R or RH terminal on the thermostat and the other wire to the W terminal. You can also try taking the wires you have and one by one twisting them together and have a second person inform you when the heating system turns on. Take those two wires and hook them to the terminals I mentioned above.

Jan 14, 2010 | Honeywell Programmable Thermostat Heater

1 Answer

Where to hook up wires?


First, take the old thermostat off the wall.

there should be different colored wires coming out of the wall still connected to the old thermo.

on the new thermo, there might be a wire color chart in the instructions or on the inside of the new thermo.

You should be able to line up the colors and install them that way. let me know if you have any other problems

Jan 12, 2009 | Honeywell Programmable Thermostat Heater

1 Answer

Thermostat wiring for second ac unit


I replaced one unite with another and the wires are differance colors the old unites wires are red,purple,yellow,bleck and white the new one have orange,brown,cream,darkpurple,and white

Aug 01, 2008 | Dometic Rooftop RV Air Conditioner

1 Answer

Im setting up a thermostat and im confused about the color wiring


How many wires do you have and what color are they?
Red is power to the thermostat, White generally goes to W1, yellow to cooling Y terminal, Green to G terminal. If you have different colors the set-up may be a little different. You can check at the unit which should have a terminal board which would also indicate which wires go to which terminals.

May 03, 2008 | Heating & Cooling

Not finding what you are looking for?
Heating & Cooling Logo

Related Topics:

1,020 people viewed this question

Ask a Question

Usually answered in minutes!

Top Honeywell Heating & Cooling Experts

Bill Long

Level 3 Expert

587 Answers

paulcarew

Level 3 Expert

2364 Answers

Brandon Berry
Brandon Berry

Level 2 Expert

407 Answers

Are you a Honeywell Heating and Cooling Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...