Ask Experts Questions for FREE Help !
Ask
    hvacgal's Avatar
    hvacgal Posts: 23, Reputation: 6
    New Member
    		  
    #1

    Jan 31, 2009, 11:29 AM
    Old mercury honeywell to new digital honeywell
    Hey,

    Old honey well thermostat is set up as follows.

    R- Red
    RH- black
    W- White
    Y- black
    G- Green

    New thermostat terminals are as follows

    R
    RC
    W
    Y
    G

    Help which wire do I wire into the RC the old R or the old RH... when I tried the RH it didn't work and it is an old furnace so tracing the wires back was useless couldn't see where they go.

    Thanks
    hvacgal's Avatar
    hvacgal Posts: 23, Reputation: 6
    New Member
    		  
    #2

    Jan 31, 2009, 12:06 PM

    Just adding on as per 1000's advice

    Furnace is GAS- has a water source Heat pump next to the furnace.

    Can't say the name of the furnace as it is old and couldn't find model numbers

    The high limit fan control is buggered and requires replacement have to keep fan running all the time

    New tstat is the Pro 6000 honeywell old one is mercury round stat model number unable to read.

    Hope that helps
    royboy74's Avatar
    royboy74 Posts: 21, Reputation: 1
    New Member
    		  
    #3

    Jan 31, 2009, 11:05 PM

    Do you have a/c? The red and white are for heat the y for a/c if it is heat try red to rh white to w you can put g on green there may be a jumper between rc and rh check this
    hvacgal's Avatar
    hvacgal Posts: 23, Reputation: 6
    New Member
    		  
    #4

    Feb 12, 2009, 02:38 PM
    Figured it out here is the answer if anyone else comes across it...

    Old honey well thermostat is set up as follows.

    R- Red
    RH- black
    W- White
    Y- black
    G- Green

    New thermostat terminals are as follows and you attach the old wires as such

    R to old RH (heating 24v)
    RC--- to old R (cooling 24v)
    W--- to W (heating )
    Y --- to Black (cooling)
    G --- G (FAN)


    Thanks all!
Not your question? Ask your question View similar questions
 

Question Tools Search this Question
Search this Question:

Advanced Search

Add your answer here.


Check out some similar questions!

Wiring from White rodgers mercury switch thermostat to 5 wire Honeywell RTH 110B [ 3 Answers ]

Trying to get the new Honeywell Digital thermostat RTH 110B to work both in heating and cooling modes. 5 wire installation from old White rdogers thermostat. Wire colors are G Y W R Br. Have to switch the R wire with the Br wire to get fan oeprating or A/C. Then have to switch them back...

Old Honeywell thermostat - not digital [ 1 Answers ]

You have the temp setting at 70 degrees.. some cold air comes out but 2 hours later the room temp reads 80 degrees on Honeywell , Also have a room thermostat that reads 76 degrees, do I need add'l freon or the thermostat needs replacing.

Replacing Honeywell mercury with digital [ 2 Answers ]

I need someone to please please please let me know first what model this is from honeywell. It does have both EM and Aux heat. The system is electric with a Heat Pump. Main heater/blower unit is York, and the pump is a newer Carrier. My goal is to buy one of the newer Honeywell digital...

Honeywell mercury to a Honeywell programmable [ 1 Answers ]

I am trying to change out my old thermostat which uses a mercury switch to a Honeywell ct2800 programmable thermostat. The old thermostat which is also a Honeywell has just 2 wires connected to it (one red and one grey)and none of the old terminal posts have any letter markings. There is no...

Honeywell digital thermostat [ 1 Answers ]

Blinking house with #2 inside this picture, what does this represent/mean?

View more questions Search