using thermostat in cool/heat mode

Discussion in 'C-Bus Wired Hardware' started by CABrouwes, Apr 12, 2012.

  1. CABrouwes

    CABrouwes

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    I have a two separate HVAC systems with plants that are capable of both cooling and heating. Each system is controlled by a 4-zone programmable thermostat. My home is experiences wide temperature variations and cooling is often needed during the day while heating is needed at night.

    I would like not to have to switch the system between cooling and heating at least twice a day.

    How to achieve that?

    1. I tried setting up the thermostat on cool/heat but it is very inefficient because it tries to keep the temperature within a much too tight temperature band and runs much more than needed. I would be happy if the temperature stayed within 2 C instead.
    2. I look into using the set back function but the narrower temperature band it can be set to is 4 c. I think this is too much variation. Especially because there is at least 1C if difference in temperature within the home si the effective temperature variation is more like 6 C. (also I would like the fall back function to be available when the home is unoccupied).

    Is the a solution?

    For example:

    1. Is there a way to set up the thermostat to do what I want ?
    1. Should I play with the PID parameters?
    3. Can I use the wiser to remotely switch over the thermostat from cool to heat and adjust the temperature setting (I never look into that).
    4. Can it be done from a PC running Cgate (I have never used C-gate).

    Thanks
     
    CABrouwes, Apr 12, 2012
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  2. CABrouwes

    Darren Senior Member

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    You could write some logic code to change the HVAC mode between heat and cool. It would probably be quite simple, but needs a bit of thinking first to make sure you come up with the right algorithm.
     
    Darren, Apr 12, 2012
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  3. CABrouwes

    CABrouwes

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    I guess that means that parameters such as heating/cooling mode, current temperature and set temperature are accessible and modifiable from program logics, correct ? (i have never checked but if it is the case, I am confident I will manage).
     
    CABrouwes, Apr 12, 2012
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  4. CABrouwes

    ashleigh Moderator

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    Don't change the PID parameters!

    PID tuning is only for the experts and you need to allow a week for testing that SMALL changes have the desired effect.

    I had thought you could change the amount of setback using C-Bus Toolkit, but it is now a while since I looked at this part of it.
     
    ashleigh, Apr 13, 2012
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  5. CABrouwes

    Darren Senior Member

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    These are all available via In-built System IO Variables.
     
    Darren, Apr 14, 2012
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