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Taco Zone valve replacement

(1) I currently have a Taco ZCV 403 zone valve control module, this module only will accept a 2 wire thermostat 24v (red/white) I would like to change the control module so that i can install a smart Thermostat (3 wire). Also this is a 2 zone system. (2)The other issue i have is i use a wood burning stove in the main floor of the house so it heats up nicely, the fire goes out then the system calls for heat it has a hard time reaching to the set point also this is a in floor radiant heat. (3) the heating system is a TAKAGI, I know all the issues with using a tank less HTR for in floor heating which i will take any good replacement recommends! the other issue is if the unit is heating the house i.e.. the wood stove off all day the unit has issues reaching set temp.it may take a few day's of running to just keep the house at 70 deg F, my flow Rate is about 3.0, The Delta T is 12 Deg F difference. the out temp of the water is 158 running through 3/4" shark bite. I have shot the floor with a Flir Thermal camera and the install in the floor looks good.

Comments

  • JohnNY
    JohnNY Member Posts: 3,064
    Is there a question in this post somewhere I'm not seeing?
    Contact John "JohnNY" Cataneo, NYC Master Plumber, Lic 1784
    Consulting
    Plumbing in NYC or in NJ.
    Take his class.
  • HVACNUT
    HVACNUT Member Posts: 4,875
    edited October 2018
    > @Evergreen said:
    > (1) I currently have a Taco ZCV 403 zone valve control module, this module only will accept a 2 wire thermostat 24v (red/white) I would like to change the control module so that i can install a smart Thermostat (3 wire). Also this is a 2 zone system.

    You might not need to upgrade.
    Is the so called 'smart thermostat' heat only, or is air conditioning being used as well?
    Your control seems to be an earlier revision than the specs I have, but if you have an electrical meter, you should be able to get the common from the internal transformer. More on that later if you have a meter and it can be done without it looking like MacGyver did it.

    What are you looking to achieve with a smart thermostat, especially if theres a problem maintaining the set temp now. Smart thermostats IMO are not all that smart.

    (2)The other issue i have is i use a wood burning stove in the main floor of the house so it heats up nicely, the fire goes out then the system calls for heat it has a hard time reaching to the set point also this is a in floor radiant heat.

    That's gonna be a problem. Assuming theres no floor sensor for the radiant or it's too close to the stove, a radiant zone should almost never shut off. Its supposed to provide a constant, even temperature. So with the stove on and the thermostat satisfied, when the thermostat calls, the radiant starts a very long uphill battle.

    (3) the heating system is a TAKAGI, I know all the issues with using a tank less HTR for in floor heating which i will take any good replacement recommends! the other issue is if the unit is heating the house i.e.. the wood stove off all day the unit has issues reaching set temp.it may take a few day's of running to just keep the house at 70 deg F, my flow Rate is about 3.0, The Delta T is 12 Deg F difference. the out temp of the water is 158 running through 3/4" shark bite. I have shot the floor with a Flir Thermal camera and the install in the floor looks good.

    Post some pics of the boiler and and the near boiler piping and we'll revisit (3).

    Also post a pic of the ZVC board.