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Timh1995's avatar
Timh1995
Explorer
Jan 23, 2021

Honeywell thermostat to replace duotherm thermostat

Hi there. Recently we decided we wanted to upgrade the thermostat in our rv and I was reading online it wouldn't be too hard to install a home thermostat. So far it's kind of working. I'm able to turn on the heat and it does toggle on and off the problem is I don't have either the low speed or high speed fan wire attached. When I do and I turn on the heat the ac vent on the roof turns on. I have the switch on the thermostat set to auto but it doesn't matter. So for the time being I just have the low speed fan wire off the thermostat since it's still cold out. Any idea why when I turn the heat on the vent on the roof comes on? The old model thermostat is a duotherm 3107612.008 and the honeywell I picked up is a honeywell rth111 and I have the toggle on the back of the thermostat set to electric-hwat pump and set the advanced settings on function 5 to setting 3 which is heat pump, hot water or high efficiency furnace.
  • Timh1995's avatar
    Timh1995
    Explorer
    Jan 23, 2021
    Old-Biscuit wrote:
    ***Link Removed***


    That is extremely not helpful. I just bought the thermostat so of course I have the manual.
  • DrewE's avatar
    DrewE
    Explorer II
    Jan 23, 2021
    Set the switch on the thermostat to the "gas or oil" setting. Your furnace controls its own fan, rather than having the thermostat control the fan when heat is called for.
  • BFL13's avatar
    BFL13
    Explorer II
    Jan 23, 2021
    What is your RV fitted with for heating and air conditioning by equipment model? Not clear why you chose heat pump instead of gas.

    I have the RTH111 but only for the furnace in the Class C, no air conditioner. Just have one tstat wire in W and the other in R, jumper left in.

    Which exact Duotherm wires (say colour too) did you put in which exact RTH111 connections? Might be a mis-wiring.
  • Timh1995's avatar
    Timh1995
    Explorer
    Jan 23, 2021
    DrewE wrote:
    Set the switch on the thermostat to the "gas or oil" setting. Your furnace controls its own fan, rather than having the thermostat control the fan when heat is called for.


    Ok I'll give that a try. I wasn't sure what to set it to. Now that I think about it it makes sense
  • Timh1995's avatar
    Timh1995
    Explorer
    Jan 23, 2021
    BFL13 wrote:
    What is your RV fitted with for heating and air conditioning by equipment model? Not clear why you chose heat pump instead of gas.

    I have the RTH111 but only for the furnace in the Class C, no air conditioner. Just have one tstat wire in W and the other in R, jumper left in.

    Which exact Duotherm wires (say colour too) did you put in which exact RTH111 connections? Might be a mis-wiring.


    My rv is fitted with heat and AC. http://i.imgur.com/q2QeXnjl.jpg
    I followed this as a guide. Something tells me it was because I didn't have it set to gas is more that likely what the problem is.
  • BFL13's avatar
    BFL13
    Explorer II
    Jan 23, 2021
    https://i.imgur.com/q2QeXnjl.jpg

    I don't understand having Hi-Fan (Blue) on G with Fan (orange or tan).

    The manual confusingly says you choose heat pump instead of gas, "... (This setting is for systems that allow the thermostat to control the fan in a call for heat, if a fan wire is connected to the G terminal.)"

    But the fan is for the air conditioner, not the furnace.
  • Old-Biscuit's avatar
    Old-Biscuit
    Explorer III
    Jan 23, 2021
    Timh1995 wrote:
    Old-Biscuit wrote:
    ***Link Removed***


    That is extremely not helpful. I just bought the thermostat so of course I have the manual.


    Wiring diagram and instructions.......
    Your post left the impression you couldn't wire it up per instructions
    Either you have a Heat Pump with AC Unit and you wire it for that
    OR
    You have AC Unit and Furnace.....wire it for that

    And set it to Gas vs Electric--Heat setting


    In the future I will NOT bother with your posts
  • Timh1995's avatar
    Timh1995
    Explorer
    Jan 23, 2021
    Old-Biscuit wrote:
    Timh1995 wrote:
    Old-Biscuit wrote:
    ***Link Removed***


    That is extremely not helpful. I just bought the thermostat so of course I have the manual.


    Wiring diagram and instructions.......
    Your post left the impression you couldn't wire it up per instructions
    Either you have a Heat Pump with AC Unit and you wire it for that
    OR
    You have AC Unit and Furnace.....wire it for that

    And set it to Gas vs Electric--Heat setting


    In the future I will NOT bother with your posts


    Cool bro, I did wire it per instructions. I'm assuming from other users that bothered to type anything that it was because I swapped it from gas furnace without realizing I made a mistake.

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